Split the mpeg4 encoder and decoder off h263.c

Originally committed as revision 21079 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/Makefile

@@ -124,10 +124,10 @@ OBJS-$(CONFIG_H261_ENCODER)            += h261enc.o h261.o             \
                                           mpegvideo_enc.o motion_est.o \
                                           ratecontrol.o mpeg12data.o   \
                                           mpegvideo.o
-OBJS-$(CONFIG_H263_DECODER)            += h263dec.o h263.o flvdec.o intelh263dec.o \
+OBJS-$(CONFIG_H263_DECODER)            += h263dec.o h263.o mpeg4video.o mpeg4videodec.o flvdec.o intelh263dec.o \
                                           mpegvideo.o error_resilience.o
 OBJS-$(CONFIG_H263_VAAPI_HWACCEL)      += vaapi_mpeg4.o
-OBJS-$(CONFIG_H263_ENCODER)            += mpegvideo_enc.o motion_est.o      \
+OBJS-$(CONFIG_H263_ENCODER)            += mpegvideo_enc.o mpeg4video.o mpeg4videoenc.o motion_est.o      \
                                           ratecontrol.o h263.o flvenc.o mpeg12data.o \
                                           mpegvideo.o error_resilience.o
 OBJS-$(CONFIG_H264_DECODER)            += h264.o h264idct.o h264pred.o cabac.o \

libavcodec/h263.h

+/*
+ * H263 internal header
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#ifndef AVCODEC_H263_H
+#define AVCODEC_H263_H
+
+// The defines below define the number of bits that are read at once for
+// reading vlc values. Changing these may improve speed and data cache needs
+// be aware though that decreasing them may need the number of stages that is
+// passed to get_vlc* to be increased.
+#define INTRA_MCBPC_VLC_BITS 6
+#define INTER_MCBPC_VLC_BITS 7
+#define CBPY_VLC_BITS 6
+#define TEX_VLC_BITS 9
+
+extern const AVRational ff_h263_pixel_aspect[16];
+extern const uint8_t cbpy_tab[16][2];
+
+extern const uint8_t mvtab[33][2];
+
+extern const uint8_t intra_MCBPC_code[9];
+extern const uint8_t intra_MCBPC_bits[9];
+
+extern const uint8_t inter_MCBPC_code[28];
+extern const uint8_t inter_MCBPC_bits[28];
+
+extern VLC intra_MCBPC_vlc;
+extern VLC inter_MCBPC_vlc;
+extern VLC cbpy_vlc;
+
+extern RLTable rl_inter;
+
+int h263_decode_motion(MpegEncContext * s, int pred, int f_code);
+av_const int ff_h263_aspect_to_info(AVRational aspect);
+
+static inline int h263_get_motion_length(MpegEncContext * s, int val, int f_code){
+    int l, bit_size, code;
+
+    if (val == 0) {
+        return mvtab[0][1];
+    } else {
+        bit_size = f_code - 1;
+        /* modulo encoding */
+        l= INT_BIT - 6 - bit_size;
+        val = (val<<l)>>l;
+        val--;
+        code = (val >> bit_size) + 1;
+
+        return mvtab[code][1] + 1 + bit_size;
+    }
+}
+
+static inline void ff_h263_encode_motion_vector(MpegEncContext * s, int x, int y, int f_code){
+    if(s->flags2 & CODEC_FLAG2_NO_OUTPUT){
+        skip_put_bits(&s->pb,
+            h263_get_motion_length(s, x, f_code)
+           +h263_get_motion_length(s, y, f_code));
+    }else{
+        ff_h263_encode_motion(s, x, f_code);
+        ff_h263_encode_motion(s, y, f_code);
+    }
+}
+
+static inline int get_p_cbp(MpegEncContext * s,
+                      DCTELEM block[6][64],
+                      int motion_x, int motion_y){
+    int cbp, i;
+
+    if(s->flags & CODEC_FLAG_CBP_RD){
+        int best_cbpy_score= INT_MAX;
+        int best_cbpc_score= INT_MAX;
+        int cbpc = (-1), cbpy= (-1);
+        const int offset= (s->mv_type==MV_TYPE_16X16 ? 0 : 16) + (s->dquant ? 8 : 0);
+        const int lambda= s->lambda2 >> (FF_LAMBDA_SHIFT - 6);
+
+        for(i=0; i<4; i++){
+            int score= inter_MCBPC_bits[i + offset] * lambda;
+            if(i&1) score += s->coded_score[5];
+            if(i&2) score += s->coded_score[4];
+
+            if(score < best_cbpc_score){
+                best_cbpc_score= score;
+                cbpc= i;
+            }
+        }
+
+        for(i=0; i<16; i++){
+            int score= cbpy_tab[i ^ 0xF][1] * lambda;
+            if(i&1) score += s->coded_score[3];
+            if(i&2) score += s->coded_score[2];
+            if(i&4) score += s->coded_score[1];
+            if(i&8) score += s->coded_score[0];
+
+            if(score < best_cbpy_score){
+                best_cbpy_score= score;
+                cbpy= i;
+            }
+        }
+        cbp= cbpc + 4*cbpy;
+        if ((motion_x | motion_y | s->dquant) == 0 && s->mv_type==MV_TYPE_16X16){
+            if(best_cbpy_score + best_cbpc_score + 2*lambda >= 0)
+                cbp= 0;
+        }
+
+        for (i = 0; i < 6; i++) {
+            if (s->block_last_index[i] >= 0 && ((cbp >> (5 - i))&1)==0 ){
+                s->block_last_index[i]= -1;
+                s->dsp.clear_block(s->block[i]);
+            }
+        }
+    }else{
+        cbp= 0;
+        for (i = 0; i < 6; i++) {
+            if (s->block_last_index[i] >= 0)
+                cbp |= 1 << (5 - i);
+        }
+    }
+    return cbp;
+}
+
+static inline int get_b_cbp(MpegEncContext * s, DCTELEM block[6][64],
+                            int motion_x, int motion_y, int mb_type){
+    int cbp=0, i;
+
+    if(s->flags & CODEC_FLAG_CBP_RD){
+        int score=0;
+        const int lambda= s->lambda2 >> (FF_LAMBDA_SHIFT - 6);
+
+        for(i=0; i<6; i++){
+            if(s->coded_score[i] < 0){
+                score += s->coded_score[i];
+                cbp |= 1 << (5 - i);
+            }
+        }
+
+        if(cbp){
+            int zero_score= -6;
+            if ((motion_x | motion_y | s->dquant | mb_type) == 0){
+                zero_score-= 4; //2*MV + mb_type + cbp bit
+            }
+
+            zero_score*= lambda;
+            if(zero_score <= score){
+                cbp=0;
+            }
+        }
+
+        for (i = 0; i < 6; i++) {
+            if (s->block_last_index[i] >= 0 && ((cbp >> (5 - i))&1)==0 ){
+                s->block_last_index[i]= -1;
+                s->dsp.clear_block(s->block[i]);
+            }
+        }
+    }else{
+        for (i = 0; i < 6; i++) {
+            if (s->block_last_index[i] >= 0)
+                cbp |= 1 << (5 - i);
+        }
+    }
+    return cbp;
+}
+#endif

libavcodec/h263data.h

@@ -177,7 +177,7 @@ const int8_t inter_run[102] = {
  35, 36, 37, 38, 39, 40,
 };
 
-static RLTable rl_inter = {
+RLTable rl_inter = {
     102,
     58,
     inter_vlc,
@@ -313,4 +313,23 @@ const uint8_t ff_h263_loop_filter_strength[32]={
     0, 1, 1, 2, 2, 3, 3, 4, 4, 4, 5, 5, 6, 6, 7, 7, 7, 8, 8, 8, 9, 9, 9,10,10,10,11,11,11,12,12,12
 };
 
+const AVRational ff_h263_pixel_aspect[16]={
+ {0, 1},
+ {1, 1},
+ {12, 11},
+ {10, 11},
+ {16, 11},
+ {40, 33},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+};
+
 #endif /* AVCODEC_H263DATA_H */

libavcodec/h263dec.c

@@ -34,6 +34,7 @@
 #include "msmpeg4.h"
 #include "vdpau_internal.h"
 #include "flv.h"
+#include "mpeg4video.h"
 
 //#define DEBUG
 //#define PRINT_FRAME_TIME
@@ -64,11 +65,6 @@ av_cold int ff_h263_decode_init(AVCodecContext *avctx)
         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
         break;
     case CODEC_ID_MPEG4:
-        s->decode_mb= ff_mpeg4_decode_mb;
-        s->time_increment_bits = 4; /* default value for broken headers */
-        s->h263_pred = 1;
-        s->low_delay = 0; //default, might be overriden in the vol header during header parsing
-        avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
         break;
     case CODEC_ID_MSMPEG4V1:
         s->h263_msmpeg4 = 1;
@@ -731,21 +727,6 @@ av_log(avctx, AV_LOG_DEBUG, "%"PRId64"\n", rdtsc()-time);
     return get_consumed_bytes(s, buf_size);
 }
 
-AVCodec mpeg4_decoder = {
-    "mpeg4",
-    CODEC_TYPE_VIDEO,
-    CODEC_ID_MPEG4,
-    sizeof(MpegEncContext),
-    ff_h263_decode_init,
-    NULL,
-    ff_h263_decode_end,
-    ff_h263_decode_frame,
-    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
-    .flush= ff_mpeg_flush,
-    .long_name= NULL_IF_CONFIG_SMALL("MPEG-4 part 2"),
-    .pix_fmts= ff_hwaccel_pixfmt_list_420,
-};
-
 AVCodec h263_decoder = {
     "h263",
     CODEC_TYPE_VIDEO,
@@ -816,19 +797,3 @@ AVCodec wmv1_decoder = {
     .long_name= NULL_IF_CONFIG_SMALL("Windows Media Video 7"),
     .pix_fmts= ff_pixfmt_list_420,
 };
-
-#if CONFIG_MPEG4_VDPAU_DECODER
-AVCodec mpeg4_vdpau_decoder = {
-    "mpeg4_vdpau",
-    CODEC_TYPE_VIDEO,
-    CODEC_ID_MPEG4,
-    sizeof(MpegEncContext),
-    ff_h263_decode_init,
-    NULL,
-    ff_h263_decode_end,
-    ff_h263_decode_frame,
-    CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_HWACCEL_VDPAU,
-    .long_name= NULL_IF_CONFIG_SMALL("MPEG-4 part 2 (VDPAU)"),
-    .pix_fmts= (const enum PixelFormat[]){PIX_FMT_VDPAU_MPEG4, PIX_FMT_NONE},
-};
-#endif

libavcodec/mpeg4data.h

@@ -31,43 +31,6 @@
 #include <stdint.h>
 #include "mpegvideo.h"
 
-// shapes
-#define RECT_SHAPE       0
-#define BIN_SHAPE        1
-#define BIN_ONLY_SHAPE   2
-#define GRAY_SHAPE       3
-
-#define SIMPLE_VO_TYPE             1
-#define CORE_VO_TYPE               3
-#define MAIN_VO_TYPE               4
-#define NBIT_VO_TYPE               5
-#define ARTS_VO_TYPE               10
-#define ACE_VO_TYPE                12
-#define ADV_SIMPLE_VO_TYPE         17
-
-// aspect_ratio_info
-#define EXTENDED_PAR 15
-
-//vol_sprite_usage / sprite_enable
-#define STATIC_SPRITE 1
-#define GMC_SPRITE 2
-
-#define MOTION_MARKER 0x1F001
-#define DC_MARKER     0x6B001
-
-static const int mb_type_b_map[4]= {
-    MB_TYPE_DIRECT2 | MB_TYPE_L0L1,
-    MB_TYPE_L0L1 | MB_TYPE_16x16,
-    MB_TYPE_L1 | MB_TYPE_16x16,
-    MB_TYPE_L0 | MB_TYPE_16x16,
-};
-
-#define VOS_STARTCODE        0x1B0
-#define USER_DATA_STARTCODE  0x1B2
-#define GOP_STARTCODE        0x1B3
-#define VISUAL_OBJ_STARTCODE 0x1B5
-#define VOP_STARTCODE        0x1B6
-
 /* dc encoding for mpeg4 */
 const uint8_t DCtab_lum[13][2] =
 {
@@ -143,7 +106,7 @@ const int8_t intra_run[102] = {
  15, 16, 17, 18, 19, 20,
 };
 
-static RLTable rl_intra = {
+RLTable rl_intra = {
     102,
     67,
     intra_vlc,
@@ -152,7 +115,7 @@ static RLTable rl_intra = {
 };
 
 /* Note this is identical to the intra rvlc except that it is reordered. */
-static const uint16_t inter_rvlc[170][2]={
+const uint16_t inter_rvlc[170][2]={
 {0x0006,  3},{0x0001,  4},{0x0004,  5},{0x001C,  7},
 {0x003C,  8},{0x003D,  8},{0x007C,  9},{0x00FC, 10},
 {0x00FD, 10},{0x01FC, 11},{0x01FD, 11},{0x03FC, 12},
@@ -198,7 +161,7 @@ static const uint16_t inter_rvlc[170][2]={
 {0x3F7C, 15},{0x3F7D, 15},{0x0000, 4}
 };
 
-static const int8_t inter_rvlc_run[169]={
+const int8_t inter_rvlc_run[169]={
  0,  0,  0,  0,  0,  0,  0,  0,
  0,  0,  0,  0,  0,  0,  0,  0,
  0,  0,  0,  1,  1,  1,  1,  1,
@@ -223,7 +186,7 @@ static const int8_t inter_rvlc_run[169]={
 43, 44,
 };
 
-static const int8_t inter_rvlc_level[169]={
+const int8_t inter_rvlc_level[169]={
  1,  2,  3,  4,  5,  6,  7,  8,
  9, 10, 11, 12, 13, 14, 15, 16,
 17, 18, 19,  1,  2,  3,  4,  5,
@@ -248,7 +211,7 @@ static const int8_t inter_rvlc_level[169]={
  1,  1,
 };
 
-static RLTable rvlc_rl_inter = {
+RLTable rvlc_rl_inter = {
     169,
     103,
     inter_rvlc,
@@ -256,7 +219,7 @@ static RLTable rvlc_rl_inter = {
     inter_rvlc_level,
 };
 
-static const uint16_t intra_rvlc[170][2]={
+const uint16_t intra_rvlc[170][2]={
 {0x0006,  3},{0x0007,  3},{0x000A,  4},{0x0009,  5},
 {0x0014,  6},{0x0015,  6},{0x0034,  7},{0x0074,  8},
 {0x0075,  8},{0x00DD,  9},{0x00EC,  9},{0x01EC, 10},
@@ -302,7 +265,7 @@ static const uint16_t intra_rvlc[170][2]={
 {0x3F7C, 15},{0x3F7D, 15},{0x0000,  4}
 };
 
-static const int8_t intra_rvlc_run[169]={
+const int8_t intra_rvlc_run[169]={
  0,  0,  0,  0,  0,  0,  0,  0,
  0,  0,  0,  0,  0,  0,  0,  0,
  0,  0,  0,  0,  0,  0,  0,  0,
@@ -327,7 +290,7 @@ static const int8_t intra_rvlc_run[169]={
 43, 44,
 };
 
-static const int8_t intra_rvlc_level[169]={
+const int8_t intra_rvlc_level[169]={
  1,  2,  3,  4,  5,  6,  7,  8,
  9, 10, 11, 12, 13, 14, 15, 16,
 17, 18, 19, 20, 21, 22, 23, 24,
@@ -352,7 +315,7 @@ static const int8_t intra_rvlc_level[169]={
  1,  1,
 };
 
-static RLTable rvlc_rl_intra = {
+RLTable rvlc_rl_intra = {
     169,
     103,
     intra_rvlc,
@@ -360,35 +323,16 @@ static RLTable rvlc_rl_intra = {
     intra_rvlc_level,
 };
 
-static const uint16_t sprite_trajectory_tab[15][2] = {
+const uint16_t sprite_trajectory_tab[15][2] = {
  {0x00, 2}, {0x02, 3},  {0x03, 3},  {0x04, 3}, {0x05, 3}, {0x06, 3},
  {0x0E, 4}, {0x1E, 5},  {0x3E, 6},  {0x7E, 7}, {0xFE, 8},
  {0x1FE, 9},{0x3FE, 10},{0x7FE, 11},{0xFFE, 12},
 };
 
-static const uint8_t mb_type_b_tab[4][2] = {
+const uint8_t mb_type_b_tab[4][2] = {
  {1, 1}, {1, 2}, {1, 3}, {1, 4},
 };
 
-static const AVRational pixel_aspect[16]={
- {0, 1},
- {1, 1},
- {12, 11},
- {10, 11},
- {16, 11},
- {40, 33},
- {0, 1},
- {0, 1},
- {0, 1},
- {0, 1},
- {0, 1},
- {0, 1},
- {0, 1},
- {0, 1},
- {0, 1},
- {0, 1},
-};
-
 /* these matrixes will be permuted for the idct */
 const int16_t ff_mpeg4_default_intra_matrix[64] = {
   8, 17, 18, 19, 21, 23, 25, 27,
@@ -425,7 +369,7 @@ const uint16_t ff_mpeg4_resync_prefix[8]={
     0x7F00, 0x7E00, 0x7C00, 0x7800, 0x7000, 0x6000, 0x4000, 0x0000
 };
 
-static const uint8_t mpeg4_dc_threshold[8]={
+const uint8_t mpeg4_dc_threshold[8]={
     99, 13, 15, 17, 19, 21, 23, 0
 };
 

libavcodec/mpeg4video.c

+/*
+ * MPEG4 decoder / encoder common code.
+ * Copyright (c) 2000,2001 Fabrice Bellard
+ * Copyright (c) 2002-2010 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "mpegvideo.h"
+#include "mpeg4video.h"
+#include "mpeg4data.h"
+
+uint8_t ff_mpeg4_static_rl_table_store[3][2][2*MAX_RUN + MAX_LEVEL + 3];
+
+int ff_mpeg4_get_video_packet_prefix_length(MpegEncContext *s){
+    switch(s->pict_type){
+        case FF_I_TYPE:
+            return 16;
+        case FF_P_TYPE:
+        case FF_S_TYPE:
+            return s->f_code+15;
+        case FF_B_TYPE:
+            return FFMAX3(s->f_code, s->b_code, 2) + 15;
+        default:
+            return -1;
+    }
+}
+
+void ff_mpeg4_clean_buffers(MpegEncContext *s)
+{
+    int c_wrap, c_xy, l_wrap, l_xy;
+
+    l_wrap= s->b8_stride;
+    l_xy= (2*s->mb_y-1)*l_wrap + s->mb_x*2 - 1;
+    c_wrap= s->mb_stride;
+    c_xy= (s->mb_y-1)*c_wrap + s->mb_x - 1;
+
+#if 0
+    /* clean DC */
+    memsetw(s->dc_val[0] + l_xy, 1024, l_wrap*2+1);
+    memsetw(s->dc_val[1] + c_xy, 1024, c_wrap+1);
+    memsetw(s->dc_val[2] + c_xy, 1024, c_wrap+1);
+#endif
+
+    /* clean AC */
+    memset(s->ac_val[0] + l_xy, 0, (l_wrap*2+1)*16*sizeof(int16_t));
+    memset(s->ac_val[1] + c_xy, 0, (c_wrap  +1)*16*sizeof(int16_t));
+    memset(s->ac_val[2] + c_xy, 0, (c_wrap  +1)*16*sizeof(int16_t));
+
+    /* clean MV */
+    // we can't clear the MVs as they might be needed by a b frame
+//    memset(s->motion_val + l_xy, 0, (l_wrap*2+1)*2*sizeof(int16_t));
+//    memset(s->motion_val, 0, 2*sizeof(int16_t)*(2 + s->mb_width*2)*(2 + s->mb_height*2));
+    s->last_mv[0][0][0]=
+    s->last_mv[0][0][1]=
+    s->last_mv[1][0][0]=
+    s->last_mv[1][0][1]= 0;
+}

libavcodec/mpeg4video.h

+/*
+ * MPEG4 encoder/decoder internal header.
+ * Copyright (c) 2000,2001 Fabrice Bellard
+ * Copyright (c) 2002-2010 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_MPEG4VIDEO_H
+#define AVCODEC_MPEG4VIDEO_H
+
+// shapes
+#define RECT_SHAPE       0
+#define BIN_SHAPE        1
+#define BIN_ONLY_SHAPE   2
+#define GRAY_SHAPE       3
+
+#define SIMPLE_VO_TYPE             1
+#define CORE_VO_TYPE               3
+#define MAIN_VO_TYPE               4
+#define NBIT_VO_TYPE               5
+#define ARTS_VO_TYPE               10
+#define ACE_VO_TYPE                12
+#define ADV_SIMPLE_VO_TYPE         17
+
+// aspect_ratio_info
+#define EXTENDED_PAR 15
+
+//vol_sprite_usage / sprite_enable
+#define STATIC_SPRITE 1
+#define GMC_SPRITE 2
+
+#define MOTION_MARKER 0x1F001
+#define DC_MARKER     0x6B001
+
+#define VOS_STARTCODE        0x1B0
+#define USER_DATA_STARTCODE  0x1B2
+#define GOP_STARTCODE        0x1B3
+#define VISUAL_OBJ_STARTCODE 0x1B5
+#define VOP_STARTCODE        0x1B6
+
+/* dc encoding for mpeg4 */
+extern const uint8_t DCtab_lum[13][2];
+extern const uint8_t DCtab_chrom[13][2];
+
+extern const uint16_t intra_vlc[103][2];
+extern const int8_t intra_level[102];
+extern const int8_t intra_run[102];
+extern RLTable rl_intra;
+
+/* Note this is identical to the intra rvlc except that it is reordered. */
+extern const uint16_t inter_rvlc[170][2];
+extern const int8_t inter_rvlc_run[169];
+extern const int8_t inter_rvlc_level[169];
+extern RLTable rvlc_rl_inter;
+
+extern const uint16_t intra_rvlc[170][2];
+extern const int8_t intra_rvlc_run[169];
+extern const int8_t intra_rvlc_level[169];
+extern RLTable rvlc_rl_intra;
+
+extern const uint16_t sprite_trajectory_tab[15][2];
+extern const uint8_t mb_type_b_tab[4][2];
+extern const AVRational pixel_aspect[16];
+
+/* these matrixes will be permuted for the idct */
+extern const int16_t ff_mpeg4_default_intra_matrix[64];
+extern const int16_t ff_mpeg4_default_non_intra_matrix[64];
+
+extern const uint8_t ff_mpeg4_y_dc_scale_table[32];
+extern const uint8_t ff_mpeg4_c_dc_scale_table[32];
+extern const uint16_t ff_mpeg4_resync_prefix[8];
+
+extern const uint8_t mpeg4_dc_threshold[8];
+
+void mpeg4_encode_mb(MpegEncContext *s,
+                    DCTELEM block[6][64],
+                    int motion_x, int motion_y);
+void mpeg4_pred_ac(MpegEncContext * s, DCTELEM *block, int n,
+                   int dir);
+void ff_set_mpeg4_time(MpegEncContext * s);
+void mpeg4_encode_picture_header(MpegEncContext *s, int picture_number);
+
+int ff_mpeg4_decode_picture_header(MpegEncContext * s, GetBitContext *gb);
+void ff_mpeg4_encode_video_packet_header(MpegEncContext *s);
+void ff_mpeg4_clean_buffers(MpegEncContext *s);
+void ff_mpeg4_stuffing(PutBitContext * pbc);
+void ff_mpeg4_init_partitions(MpegEncContext *s);
+void ff_mpeg4_merge_partitions(MpegEncContext *s);
+void ff_clean_mpeg4_qscales(MpegEncContext *s);
+int ff_mpeg4_decode_partitions(MpegEncContext *s);
+int ff_mpeg4_get_video_packet_prefix_length(MpegEncContext *s);
+int mpeg4_decode_video_packet_header(MpegEncContext *s);
+
+extern uint8_t ff_mpeg4_static_rl_table_store[3][2][2*MAX_RUN + MAX_LEVEL + 3];
+
+
+#if 0 //3IV1 is quite rare and it slows things down a tiny bit
+#define IS_3IV1 s->codec_tag == AV_RL32("3IV1")
+#else
+#define IS_3IV1 0
+#endif
+
+
+/**
+ * predicts the dc.
+ * encoding quantized level -> quantized diff
+ * decoding quantized diff -> quantized level
+ * @param n block index (0-3 are luma, 4-5 are chroma)
+ * @param dir_ptr pointer to an integer where the prediction direction will be stored
+ */
+static inline int ff_mpeg4_pred_dc(MpegEncContext * s, int n, int level, int *dir_ptr, int encoding)
+{
+    int a, b, c, wrap, pred, scale, ret;
+    int16_t *dc_val;
+
+    /* find prediction */
+    if (n < 4) {
+        scale = s->y_dc_scale;
+    } else {
+        scale = s->c_dc_scale;
+    }
+    if(IS_3IV1)
+        scale= 8;
+
+    wrap= s->block_wrap[n];
+    dc_val = s->dc_val[0] + s->block_index[n];
+
+    /* B C
+     * A X
+     */
+    a = dc_val[ - 1];
+    b = dc_val[ - 1 - wrap];
+    c = dc_val[ - wrap];
+
+    /* outside slice handling (we can't do that by memset as we need the dc for error resilience) */
+    if(s->first_slice_line && n!=3){
+        if(n!=2) b=c= 1024;
+        if(n!=1 && s->mb_x == s->resync_mb_x) b=a= 1024;
+    }
+    if(s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y+1){
+        if(n==0 || n==4 || n==5)
+            b=1024;
+    }
+
+    if (abs(a - b) < abs(b - c)) {
+        pred = c;
+        *dir_ptr = 1; /* top */
+    } else {
+        pred = a;
+        *dir_ptr = 0; /* left */
+    }
+    /* we assume pred is positive */
+    pred = FASTDIV((pred + (scale >> 1)), scale);
+
+    if(encoding){
+        ret = level - pred;
+    }else{
+        level += pred;
+        ret= level;
+        if(s->error_recognition>=3){
+            if(level<0){
+                av_log(s->avctx, AV_LOG_ERROR, "dc<0 at %dx%d\n", s->mb_x, s->mb_y);
+                return -1;
+            }
+            if(level*scale > 2048 + scale){
+                av_log(s->avctx, AV_LOG_ERROR, "dc overflow at %dx%d\n", s->mb_x, s->mb_y);
+                return -1;
+            }
+        }
+    }
+    level *=scale;
+    if(level&(~2047)){
+        if(level<0)
+            level=0;
+        else if(!(s->workaround_bugs&FF_BUG_DC_CLIP))
+            level=2047;
+    }
+    dc_val[0]= level;
+
+    return ret;
+}
+#endif

libavcodec/mpeg4videodec.c

+/*
+ * MPEG4 decoder.
+ * Copyright (c) 2000,2001 Fabrice Bellard
+ * Copyright (c) 2002-2010 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "mpegvideo.h"
+#include "mpeg4video.h"
+#include "h263.h"
+
+// The defines below define the number of bits that are read at once for
+// reading vlc values. Changing these may improve speed and data cache needs
+// be aware though that decreasing them may need the number of stages that is
+// passed to get_vlc* to be increased.
+#define SPRITE_TRAJ_VLC_BITS 6
+#define DC_VLC_BITS 9
+#define MB_TYPE_B_VLC_BITS 4
+
+
+static VLC dc_lum, dc_chrom;
+static VLC sprite_trajectory;
+static VLC mb_type_b_vlc;
+
+static const int mb_type_b_map[4]= {
+    MB_TYPE_DIRECT2 | MB_TYPE_L0L1,
+    MB_TYPE_L0L1 | MB_TYPE_16x16,
+    MB_TYPE_L1 | MB_TYPE_16x16,
+    MB_TYPE_L0 | MB_TYPE_16x16,
+};
+
+/**
+ * predicts the ac.
+ * @param n block index (0-3 are luma, 4-5 are chroma)
+ * @param dir the ac prediction direction
+ */
+void mpeg4_pred_ac(MpegEncContext * s, DCTELEM *block, int n,
+                   int dir)
+{
+    int i;
+    int16_t *ac_val, *ac_val1;
+    int8_t * const qscale_table= s->current_picture.qscale_table;
+
+    /* find prediction */
+    ac_val = s->ac_val[0][0] + s->block_index[n] * 16;
+    ac_val1 = ac_val;
+    if (s->ac_pred) {
+        if (dir == 0) {
+            const int xy= s->mb_x-1 + s->mb_y*s->mb_stride;
+            /* left prediction */
+            ac_val -= 16;
+
+            if(s->mb_x==0 || s->qscale == qscale_table[xy] || n==1 || n==3){
+                /* same qscale */
+                for(i=1;i<8;i++) {
+                    block[s->dsp.idct_permutation[i<<3]] += ac_val[i];
+                }
+            }else{
+                /* different qscale, we must rescale */
+                for(i=1;i<8;i++) {
+                    block[s->dsp.idct_permutation[i<<3]] += ROUNDED_DIV(ac_val[i]*qscale_table[xy], s->qscale);
+                }
+            }
+        } else {
+            const int xy= s->mb_x + s->mb_y*s->mb_stride - s->mb_stride;
+            /* top prediction */
+            ac_val -= 16 * s->block_wrap[n];
+
+            if(s->mb_y==0 || s->qscale == qscale_table[xy] || n==2 || n==3){
+                /* same qscale */
+                for(i=1;i<8;i++) {
+                    block[s->dsp.idct_permutation[i]] += ac_val[i + 8];
+                }
+            }else{
+                /* different qscale, we must rescale */
+                for(i=1;i<8;i++) {
+                    block[s->dsp.idct_permutation[i]] += ROUNDED_DIV(ac_val[i + 8]*qscale_table[xy], s->qscale);
+                }
+            }
+        }
+    }
+    /* left copy */
+    for(i=1;i<8;i++)
+        ac_val1[i    ] = block[s->dsp.idct_permutation[i<<3]];
+
+    /* top copy */
+    for(i=1;i<8;i++)
+        ac_val1[8 + i] = block[s->dsp.idct_permutation[i   ]];
+
+}
+
+/**
+ * check if the next stuff is a resync marker or the end.
+ * @return 0 if not
+ */
+static inline int mpeg4_is_resync(MpegEncContext *s){
+    int bits_count= get_bits_count(&s->gb);
+    int v= show_bits(&s->gb, 16);
+
+    if(s->workaround_bugs&FF_BUG_NO_PADDING){
+        return 0;
+    }
+
+    while(v<=0xFF){
+        if(s->pict_type==FF_B_TYPE || (v>>(8-s->pict_type)!=1) || s->partitioned_frame)
+            break;
+        skip_bits(&s->gb, 8+s->pict_type);
+        bits_count+= 8+s->pict_type;
+        v= show_bits(&s->gb, 16);
+    }
+
+    if(bits_count + 8 >= s->gb.size_in_bits){
+        v>>=8;
+        v|= 0x7F >> (7-(bits_count&7));
+
+        if(v==0x7F)
+            return 1;
+    }else{
+        if(v == ff_mpeg4_resync_prefix[bits_count&7]){
+            int len;
+            GetBitContext gb= s->gb;
+
+            skip_bits(&s->gb, 1);
+            align_get_bits(&s->gb);
+
+            for(len=0; len<32; len++){
+                if(get_bits1(&s->gb)) break;
+            }
+
+            s->gb= gb;
+
+            if(len>=ff_mpeg4_get_video_packet_prefix_length(s))
+                return 1;
+        }
+    }
+    return 0;
+}
+
+static void mpeg4_decode_sprite_trajectory(MpegEncContext * s, GetBitContext *gb)
+{
+    int i;
+    int a= 2<<s->sprite_warping_accuracy;
+    int rho= 3-s->sprite_warping_accuracy;
+    int r=16/a;
+    const int vop_ref[4][2]= {{0,0}, {s->width,0}, {0, s->height}, {s->width, s->height}}; // only true for rectangle shapes
+    int d[4][2]={{0,0}, {0,0}, {0,0}, {0,0}};
+    int sprite_ref[4][2];
+    int virtual_ref[2][2];
+    int w2, h2, w3, h3;
+    int alpha=0, beta=0;
+    int w= s->width;
+    int h= s->height;
+    int min_ab;
+
+    for(i=0; i<s->num_sprite_warping_points; i++){
+        int length;
+        int x=0, y=0;
+
+        length= get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
+        if(length){
+            x= get_xbits(gb, length);
+        }
+        if(!(s->divx_version==500 && s->divx_build==413)) skip_bits1(gb); /* marker bit */
+
+        length= get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
+        if(length){
+            y=get_xbits(gb, length);
+        }
+        skip_bits1(gb); /* marker bit */
+        s->sprite_traj[i][0]= d[i][0]= x;
+        s->sprite_traj[i][1]= d[i][1]= y;
+    }
+    for(; i<4; i++)
+        s->sprite_traj[i][0]= s->sprite_traj[i][1]= 0;
+
+    while((1<<alpha)<w) alpha++;
+    while((1<<beta )<h) beta++; // there seems to be a typo in the mpeg4 std for the definition of w' and h'
+    w2= 1<<alpha;
+    h2= 1<<beta;
+
+// Note, the 4th point isn't used for GMC
+    if(s->divx_version==500 && s->divx_build==413){
+        sprite_ref[0][0]= a*vop_ref[0][0] + d[0][0];
+        sprite_ref[0][1]= a*vop_ref[0][1] + d[0][1];
+        sprite_ref[1][0]= a*vop_ref[1][0] + d[0][0] + d[1][0];
+        sprite_ref[1][1]= a*vop_ref[1][1] + d[0][1] + d[1][1];
+        sprite_ref[2][0]= a*vop_ref[2][0] + d[0][0] + d[2][0];
+        sprite_ref[2][1]= a*vop_ref[2][1] + d[0][1] + d[2][1];
+    } else {
+        sprite_ref[0][0]= (a>>1)*(2*vop_ref[0][0] + d[0][0]);
+        sprite_ref[0][1]= (a>>1)*(2*vop_ref[0][1] + d[0][1]);
+        sprite_ref[1][0]= (a>>1)*(2*vop_ref[1][0] + d[0][0] + d[1][0]);
+        sprite_ref[1][1]= (a>>1)*(2*vop_ref[1][1] + d[0][1] + d[1][1]);
+        sprite_ref[2][0]= (a>>1)*(2*vop_ref[2][0] + d[0][0] + d[2][0]);
+        sprite_ref[2][1]= (a>>1)*(2*vop_ref[2][1] + d[0][1] + d[2][1]);
+    }
+/*    sprite_ref[3][0]= (a>>1)*(2*vop_ref[3][0] + d[0][0] + d[1][0] + d[2][0] + d[3][0]);
+    sprite_ref[3][1]= (a>>1)*(2*vop_ref[3][1] + d[0][1] + d[1][1] + d[2][1] + d[3][1]); */
+
+// this is mostly identical to the mpeg4 std (and is totally unreadable because of that ...)
+// perhaps it should be reordered to be more readable ...
+// the idea behind this virtual_ref mess is to be able to use shifts later per pixel instead of divides
+// so the distance between points is converted from w&h based to w2&h2 based which are of the 2^x form
+    virtual_ref[0][0]= 16*(vop_ref[0][0] + w2)
+        + ROUNDED_DIV(((w - w2)*(r*sprite_ref[0][0] - 16*vop_ref[0][0]) + w2*(r*sprite_ref[1][0] - 16*vop_ref[1][0])),w);
+    virtual_ref[0][1]= 16*vop_ref[0][1]
+        + ROUNDED_DIV(((w - w2)*(r*sprite_ref[0][1] - 16*vop_ref[0][1]) + w2*(r*sprite_ref[1][1] - 16*vop_ref[1][1])),w);
+    virtual_ref[1][0]= 16*vop_ref[0][0]
+        + ROUNDED_DIV(((h - h2)*(r*sprite_ref[0][0] - 16*vop_ref[0][0]) + h2*(r*sprite_ref[2][0] - 16*vop_ref[2][0])),h);
+    virtual_ref[1][1]= 16*(vop_ref[0][1] + h2)
+        + ROUNDED_DIV(((h - h2)*(r*sprite_ref[0][1] - 16*vop_ref[0][1]) + h2*(r*sprite_ref[2][1] - 16*vop_ref[2][1])),h);
+
+    switch(s->num_sprite_warping_points)
+    {
+        case 0:
+            s->sprite_offset[0][0]= 0;
+            s->sprite_offset[0][1]= 0;
+            s->sprite_offset[1][0]= 0;
+            s->sprite_offset[1][1]= 0;
+            s->sprite_delta[0][0]= a;
+            s->sprite_delta[0][1]= 0;
+            s->sprite_delta[1][0]= 0;
+            s->sprite_delta[1][1]= a;
+            s->sprite_shift[0]= 0;
+            s->sprite_shift[1]= 0;
+            break;
+        case 1: //GMC only
+            s->sprite_offset[0][0]= sprite_ref[0][0] - a*vop_ref[0][0];
+            s->sprite_offset[0][1]= sprite_ref[0][1] - a*vop_ref[0][1];
+            s->sprite_offset[1][0]= ((sprite_ref[0][0]>>1)|(sprite_ref[0][0]&1)) - a*(vop_ref[0][0]/2);
+            s->sprite_offset[1][1]= ((sprite_ref[0][1]>>1)|(sprite_ref[0][1]&1)) - a*(vop_ref[0][1]/2);
+            s->sprite_delta[0][0]= a;
+            s->sprite_delta[0][1]= 0;
+            s->sprite_delta[1][0]= 0;
+            s->sprite_delta[1][1]= a;
+            s->sprite_shift[0]= 0;
+            s->sprite_shift[1]= 0;
+            break;
+        case 2:
+            s->sprite_offset[0][0]= (sprite_ref[0][0]<<(alpha+rho))
+                                                  + (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-vop_ref[0][0])
+                                                  + ( r*sprite_ref[0][1] - virtual_ref[0][1])*(-vop_ref[0][1])
+                                                  + (1<<(alpha+rho-1));
+            s->sprite_offset[0][1]= (sprite_ref[0][1]<<(alpha+rho))
+                                                  + (-r*sprite_ref[0][1] + virtual_ref[0][1])*(-vop_ref[0][0])
+                                                  + (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-vop_ref[0][1])
+                                                  + (1<<(alpha+rho-1));
+            s->sprite_offset[1][0]= ( (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-2*vop_ref[0][0] + 1)
+                                     +( r*sprite_ref[0][1] - virtual_ref[0][1])*(-2*vop_ref[0][1] + 1)
+                                     +2*w2*r*sprite_ref[0][0]
+                                     - 16*w2
+                                     + (1<<(alpha+rho+1)));
+            s->sprite_offset[1][1]= ( (-r*sprite_ref[0][1] + virtual_ref[0][1])*(-2*vop_ref[0][0] + 1)
+                                     +(-r*sprite_ref[0][0] + virtual_ref[0][0])*(-2*vop_ref[0][1] + 1)
+                                     +2*w2*r*sprite_ref[0][1]
+                                     - 16*w2
+                                     + (1<<(alpha+rho+1)));
+            s->sprite_delta[0][0]=   (-r*sprite_ref[0][0] + virtual_ref[0][0]);
+            s->sprite_delta[0][1]=   (+r*sprite_ref[0][1] - virtual_ref[0][1]);
+            s->sprite_delta[1][0]=   (-r*sprite_ref[0][1] + virtual_ref[0][1]);
+            s->sprite_delta[1][1]=   (-r*sprite_ref[0][0] + virtual_ref[0][0]);
+
+            s->sprite_shift[0]= alpha+rho;
+            s->sprite_shift[1]= alpha+rho+2;
+            break;
+        case 3:
+            min_ab= FFMIN(alpha, beta);
+            w3= w2>>min_ab;
+            h3= h2>>min_ab;
+            s->sprite_offset[0][0]=  (sprite_ref[0][0]<<(alpha+beta+rho-min_ab))
+                                   + (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3*(-vop_ref[0][0])
+                                   + (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3*(-vop_ref[0][1])
+                                   + (1<<(alpha+beta+rho-min_ab-1));
+            s->sprite_offset[0][1]=  (sprite_ref[0][1]<<(alpha+beta+rho-min_ab))
+                                   + (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3*(-vop_ref[0][0])
+                                   + (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3*(-vop_ref[0][1])
+                                   + (1<<(alpha+beta+rho-min_ab-1));
+            s->sprite_offset[1][0]=  (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3*(-2*vop_ref[0][0] + 1)
+                                   + (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3*(-2*vop_ref[0][1] + 1)
+                                   + 2*w2*h3*r*sprite_ref[0][0]
+                                   - 16*w2*h3
+                                   + (1<<(alpha+beta+rho-min_ab+1));
+            s->sprite_offset[1][1]=  (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3*(-2*vop_ref[0][0] + 1)
+                                   + (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3*(-2*vop_ref[0][1] + 1)
+                                   + 2*w2*h3*r*sprite_ref[0][1]
+                                   - 16*w2*h3
+                                   + (1<<(alpha+beta+rho-min_ab+1));
+            s->sprite_delta[0][0]=   (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3;
+            s->sprite_delta[0][1]=   (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3;
+            s->sprite_delta[1][0]=   (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3;
+            s->sprite_delta[1][1]=   (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3;
+
+            s->sprite_shift[0]= alpha + beta + rho - min_ab;
+            s->sprite_shift[1]= alpha + beta + rho - min_ab + 2;
+            break;
+    }
+    /* try to simplify the situation */
+    if(   s->sprite_delta[0][0] == a<<s->sprite_shift[0]
+       && s->sprite_delta[0][1] == 0
+       && s->sprite_delta[1][0] == 0
+       && s->sprite_delta[1][1] == a<<s->sprite_shift[0])
+    {
+        s->sprite_offset[0][0]>>=s->sprite_shift[0];
+        s->sprite_offset[0][1]>>=s->sprite_shift[0];
+        s->sprite_offset[1][0]>>=s->sprite_shift[1];
+        s->sprite_offset[1][1]>>=s->sprite_shift[1];
+        s->sprite_delta[0][0]= a;
+        s->sprite_delta[0][1]= 0;
+        s->sprite_delta[1][0]= 0;
+        s->sprite_delta[1][1]= a;
+        s->sprite_shift[0]= 0;
+        s->sprite_shift[1]= 0;
+        s->real_sprite_warping_points=1;
+    }
+    else{
+        int shift_y= 16 - s->sprite_shift[0];
+        int shift_c= 16 - s->sprite_shift[1];
+        for(i=0; i<2; i++){
+            s->sprite_offset[0][i]<<= shift_y;
+            s->sprite_offset[1][i]<<= shift_c;
+            s->sprite_delta[0][i]<<= shift_y;
+            s->sprite_delta[1][i]<<= shift_y;
+            s->sprite_shift[i]= 16;
+        }
+        s->real_sprite_warping_points= s->num_sprite_warping_points;
+    }
+}
+
+/**
+ * decodes the next video packet.
+ * @return <0 if something went wrong
+ */
+int mpeg4_decode_video_packet_header(MpegEncContext *s)
+{
+    int mb_num_bits= av_log2(s->mb_num - 1) + 1;
+    int header_extension=0, mb_num, len;
+
+    /* is there enough space left for a video packet + header */
+    if( get_bits_count(&s->gb) > s->gb.size_in_bits-20) return -1;
+
+    for(len=0; len<32; len++){
+        if(get_bits1(&s->gb)) break;
+    }
+
+    if(len!=ff_mpeg4_get_video_packet_prefix_length(s)){
+        av_log(s->avctx, AV_LOG_ERROR, "marker does not match f_code\n");
+        return -1;
+    }
+
+    if(s->shape != RECT_SHAPE){
+        header_extension= get_bits1(&s->gb);
+        //FIXME more stuff here
+    }
+
+    mb_num= get_bits(&s->gb, mb_num_bits);
+    if(mb_num>=s->mb_num){
+        av_log(s->avctx, AV_LOG_ERROR, "illegal mb_num in video packet (%d %d) \n", mb_num, s->mb_num);
+        return -1;
+    }
+    if(s->pict_type == FF_B_TYPE){
+        while(s->next_picture.mbskip_table[ s->mb_index2xy[ mb_num ] ]) mb_num++;
+        if(mb_num >= s->mb_num) return -1; // slice contains just skipped MBs which where already decoded
+    }
+
+    s->mb_x= mb_num % s->mb_width;
+    s->mb_y= mb_num / s->mb_width;
+
+    if(s->shape != BIN_ONLY_SHAPE){
+        int qscale= get_bits(&s->gb, s->quant_precision);
+        if(qscale)
+            s->chroma_qscale=s->qscale= qscale;
+    }
+
+    if(s->shape == RECT_SHAPE){
+        header_extension= get_bits1(&s->gb);
+    }
+    if(header_extension){
+        int time_increment;
+        int time_incr=0;
+
+        while (get_bits1(&s->gb) != 0)
+            time_incr++;
+
+        check_marker(&s->gb, "before time_increment in video packed header");
+        time_increment= get_bits(&s->gb, s->time_increment_bits);
+        check_marker(&s->gb, "before vop_coding_type in video packed header");
+
+        skip_bits(&s->gb, 2); /* vop coding type */
+        //FIXME not rect stuff here
+
+        if(s->shape != BIN_ONLY_SHAPE){
+            skip_bits(&s->gb, 3); /* intra dc vlc threshold */
+//FIXME don't just ignore everything
+            if(s->pict_type == FF_S_TYPE && s->vol_sprite_usage==GMC_SPRITE){
+                mpeg4_decode_sprite_trajectory(s, &s->gb);
+                av_log(s->avctx, AV_LOG_ERROR, "untested\n");
+            }
+
+            //FIXME reduced res stuff here
+
+            if (s->pict_type != FF_I_TYPE) {
+                int f_code = get_bits(&s->gb, 3);       /* fcode_for */
+                if(f_code==0){
+                    av_log(s->avctx, AV_LOG_ERROR, "Error, video packet header damaged (f_code=0)\n");
+                }
+            }
+            if (s->pict_type == FF_B_TYPE) {
+                int b_code = get_bits(&s->gb, 3);
+                if(b_code==0){
+                    av_log(s->avctx, AV_LOG_ERROR, "Error, video packet header damaged (b_code=0)\n");
+                }
+            }
+        }
+    }
+    //FIXME new-pred stuff
+
+    return 0;
+}
+
+/**
+ * gets the average motion vector for a GMC MB.
+ * @param n either 0 for the x component or 1 for y
+ * @returns the average MV for a GMC MB
+ */
+static inline int get_amv(MpegEncContext *s, int n){
+    int x, y, mb_v, sum, dx, dy, shift;
+    int len = 1 << (s->f_code + 4);
+    const int a= s->sprite_warping_accuracy;
+
+    if(s->workaround_bugs & FF_BUG_AMV)
+        len >>= s->quarter_sample;
+
+    if(s->real_sprite_warping_points==1){
+        if(s->divx_version==500 && s->divx_build==413)
+            sum= s->sprite_offset[0][n] / (1<<(a - s->quarter_sample));
+        else
+            sum= RSHIFT(s->sprite_offset[0][n]<<s->quarter_sample, a);
+    }else{
+        dx= s->sprite_delta[n][0];
+        dy= s->sprite_delta[n][1];
+        shift= s->sprite_shift[0];
+        if(n) dy -= 1<<(shift + a + 1);
+        else  dx -= 1<<(shift + a + 1);
+        mb_v= s->sprite_offset[0][n] + dx*s->mb_x*16 + dy*s->mb_y*16;
+
+        sum=0;
+        for(y=0; y<16; y++){
+            int v;
+
+            v= mb_v + dy*y;
+            //XXX FIXME optimize
+            for(x=0; x<16; x++){
+                sum+= v>>shift;
+                v+= dx;
+            }
+        }
+        sum= RSHIFT(sum, a+8-s->quarter_sample);
+    }
+
+    if      (sum < -len) sum= -len;
+    else if (sum >= len) sum= len-1;
+
+    return sum;
+}
+
+/**
+ * decodes the dc value.
+ * @param n block index (0-3 are luma, 4-5 are chroma)
+ * @param dir_ptr the prediction direction will be stored here
+ * @return the quantized dc
+ */
+static inline int mpeg4_decode_dc(MpegEncContext * s, int n, int *dir_ptr)
+{
+    int level, code;
+
+    if (n < 4)
+        code = get_vlc2(&s->gb, dc_lum.table, DC_VLC_BITS, 1);
+    else
+        code = get_vlc2(&s->gb, dc_chrom.table, DC_VLC_BITS, 1);
+    if (code < 0 || code > 9 /* && s->nbit<9 */){
+        av_log(s->avctx, AV_LOG_ERROR, "illegal dc vlc\n");
+        return -1;
+    }
+    if (code == 0) {
+        level = 0;
+    } else {
+        if(IS_3IV1){
+            if(code==1)
+                level= 2*get_bits1(&s->gb)-1;
+            else{
+                if(get_bits1(&s->gb))
+                    level = get_bits(&s->gb, code-1) + (1<<(code-1));
+                else
+                    level = -get_bits(&s->gb, code-1) - (1<<(code-1));
+            }
+        }else{
+            level = get_xbits(&s->gb, code);
+        }
+
+        if (code > 8){
+            if(get_bits1(&s->gb)==0){ /* marker */
+                if(s->error_recognition>=2){
+                    av_log(s->avctx, AV_LOG_ERROR, "dc marker bit missing\n");
+                    return -1;
+                }
+            }
+        }
+    }
+
+    return ff_mpeg4_pred_dc(s, n, level, dir_ptr, 0);
+}
+
+/**
+ * decodes first partition.
+ * @return number of MBs decoded or <0 if an error occurred
+ */
+static int mpeg4_decode_partition_a(MpegEncContext *s){
+    int mb_num;
+    static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
+
+    /* decode first partition */
+    mb_num=0;
+    s->first_slice_line=1;
+    for(; s->mb_y<s->mb_height; s->mb_y++){
+        ff_init_block_index(s);
+        for(; s->mb_x<s->mb_width; s->mb_x++){
+            const int xy= s->mb_x + s->mb_y*s->mb_stride;
+            int cbpc;
+            int dir=0;
+
+            mb_num++;
+            ff_update_block_index(s);
+            if(s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y+1)
+                s->first_slice_line=0;
+
+            if(s->pict_type==FF_I_TYPE){
+                int i;
+
+                do{
+                    if(show_bits_long(&s->gb, 19)==DC_MARKER){
+                        return mb_num-1;
+                    }
+
+                    cbpc = get_vlc2(&s->gb, intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
+                    if (cbpc < 0){
+                        av_log(s->avctx, AV_LOG_ERROR, "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
+                        return -1;
+                    }
+                }while(cbpc == 8);
+
+                s->cbp_table[xy]= cbpc & 3;
+                s->current_picture.mb_type[xy]= MB_TYPE_INTRA;
+                s->mb_intra = 1;
+
+                if(cbpc & 4) {
+                    ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
+                }
+                s->current_picture.qscale_table[xy]= s->qscale;
+
+                s->mbintra_table[xy]= 1;
+                for(i=0; i<6; i++){
+                    int dc_pred_dir;
+                    int dc= mpeg4_decode_dc(s, i, &dc_pred_dir);
+                    if(dc < 0){
+                        av_log(s->avctx, AV_LOG_ERROR, "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
+                        return -1;
+                    }
+                    dir<<=1;
+                    if(dc_pred_dir) dir|=1;
+                }
+                s->pred_dir_table[xy]= dir;
+            }else{ /* P/S_TYPE */
+                int mx, my, pred_x, pred_y, bits;
+                int16_t * const mot_val= s->current_picture.motion_val[0][s->block_index[0]];
+                const int stride= s->b8_stride*2;
+
+try_again:
+                bits= show_bits(&s->gb, 17);
+                if(bits==MOTION_MARKER){
+                    return mb_num-1;
+                }
+                skip_bits1(&s->gb);
+                if(bits&0x10000){
+                    /* skip mb */
+                    if(s->pict_type==FF_S_TYPE && s->vol_sprite_usage==GMC_SPRITE){
+                        s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_GMC | MB_TYPE_L0;
+                        mx= get_amv(s, 0);
+                        my= get_amv(s, 1);
+                    }else{
+                        s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
+                        mx=my=0;
+                    }
+                    mot_val[0       ]= mot_val[2       ]=
+                    mot_val[0+stride]= mot_val[2+stride]= mx;
+                    mot_val[1       ]= mot_val[3       ]=
+                    mot_val[1+stride]= mot_val[3+stride]= my;
+
+                    if(s->mbintra_table[xy])
+                        ff_clean_intra_table_entries(s);
+                    continue;
+                }
+
+                cbpc = get_vlc2(&s->gb, inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
+                if (cbpc < 0){
+                    av_log(s->avctx, AV_LOG_ERROR, "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
+                    return -1;
+                }
+                if(cbpc == 20)
+                    goto try_again;
+
+                s->cbp_table[xy]= cbpc&(8+3); //8 is dquant
+
+                s->mb_intra = ((cbpc & 4) != 0);
+
+                if(s->mb_intra){
+                    s->current_picture.mb_type[xy]= MB_TYPE_INTRA;
+                    s->mbintra_table[xy]= 1;
+                    mot_val[0       ]= mot_val[2       ]=
+                    mot_val[0+stride]= mot_val[2+stride]= 0;
+                    mot_val[1       ]= mot_val[3       ]=
+                    mot_val[1+stride]= mot_val[3+stride]= 0;
+                }else{
+                    if(s->mbintra_table[xy])
+                        ff_clean_intra_table_entries(s);
+
+                    if(s->pict_type==FF_S_TYPE && s->vol_sprite_usage==GMC_SPRITE && (cbpc & 16) == 0)
+                        s->mcsel= get_bits1(&s->gb);
+                    else s->mcsel= 0;
+
+                    if ((cbpc & 16) == 0) {
+                        /* 16x16 motion prediction */
+
+                        h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
+                        if(!s->mcsel){
+                            mx = h263_decode_motion(s, pred_x, s->f_code);
+                            if (mx >= 0xffff)
+                                return -1;
+
+                            my = h263_decode_motion(s, pred_y, s->f_code);
+                            if (my >= 0xffff)
+                                return -1;
+                            s->current_picture.mb_type[xy]= MB_TYPE_16x16 | MB_TYPE_L0;
+                        } else {
+                            mx = get_amv(s, 0);
+                            my = get_amv(s, 1);
+                            s->current_picture.mb_type[xy]= MB_TYPE_16x16 | MB_TYPE_GMC | MB_TYPE_L0;
+                        }
+
+                        mot_val[0       ]= mot_val[2       ] =
+                        mot_val[0+stride]= mot_val[2+stride]= mx;
+                        mot_val[1       ]= mot_val[3       ]=
+                        mot_val[1+stride]= mot_val[3+stride]= my;
+                    } else {
+                        int i;
+                        s->current_picture.mb_type[xy]= MB_TYPE_8x8 | MB_TYPE_L0;
+                        for(i=0;i<4;i++) {
+                            int16_t *mot_val= h263_pred_motion(s, i, 0, &pred_x, &pred_y);
+                            mx = h263_decode_motion(s, pred_x, s->f_code);
+                            if (mx >= 0xffff)
+                                return -1;
+
+                            my = h263_decode_motion(s, pred_y, s->f_code);
+                            if (my >= 0xffff)
+                                return -1;
+                            mot_val[0] = mx;
+                            mot_val[1] = my;
+                        }
+                    }
+                }
+            }
+        }
+        s->mb_x= 0;
+    }
+
+    return mb_num;
+}
+
+/**
+ * decode second partition.
+ * @return <0 if an error occurred
+ */
+static int mpeg4_decode_partition_b(MpegEncContext *s, int mb_count){
+    int mb_num=0;
+    static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
+
+    s->mb_x= s->resync_mb_x;
+    s->first_slice_line=1;
+    for(s->mb_y= s->resync_mb_y; mb_num < mb_count; s->mb_y++){
+        ff_init_block_index(s);
+        for(; mb_num < mb_count && s->mb_x<s->mb_width; s->mb_x++){
+            const int xy= s->mb_x + s->mb_y*s->mb_stride;
+
+            mb_num++;
+            ff_update_block_index(s);
+            if(s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y+1)
+                s->first_slice_line=0;
+
+            if(s->pict_type==FF_I_TYPE){
+                int ac_pred= get_bits1(&s->gb);
+                int cbpy = get_vlc2(&s->gb, cbpy_vlc.table, CBPY_VLC_BITS, 1);
+                if(cbpy<0){
+                    av_log(s->avctx, AV_LOG_ERROR, "cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
+                    return -1;
+                }
+
+                s->cbp_table[xy]|= cbpy<<2;
+                s->current_picture.mb_type[xy] |= ac_pred*MB_TYPE_ACPRED;
+            }else{ /* P || S_TYPE */
+                if(IS_INTRA(s->current_picture.mb_type[xy])){
+                    int dir=0,i;
+                    int ac_pred = get_bits1(&s->gb);
+                    int cbpy = get_vlc2(&s->gb, cbpy_vlc.table, CBPY_VLC_BITS, 1);
+
+                    if(cbpy<0){
+                        av_log(s->avctx, AV_LOG_ERROR, "I cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
+                        return -1;
+                    }
+
+                    if(s->cbp_table[xy] & 8) {
+                        ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
+                    }
+                    s->current_picture.qscale_table[xy]= s->qscale;
+
+                    for(i=0; i<6; i++){
+                        int dc_pred_dir;
+                        int dc= mpeg4_decode_dc(s, i, &dc_pred_dir);
+                        if(dc < 0){
+                            av_log(s->avctx, AV_LOG_ERROR, "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
+                            return -1;
+                        }
+                        dir<<=1;
+                        if(dc_pred_dir) dir|=1;
+                    }
+                    s->cbp_table[xy]&= 3; //remove dquant
+                    s->cbp_table[xy]|= cbpy<<2;
+                    s->current_picture.mb_type[xy] |= ac_pred*MB_TYPE_ACPRED;
+                    s->pred_dir_table[xy]= dir;
+                }else if(IS_SKIP(s->current_picture.mb_type[xy])){
+                    s->current_picture.qscale_table[xy]= s->qscale;
+                    s->cbp_table[xy]= 0;
+                }else{
+                    int cbpy = get_vlc2(&s->gb, cbpy_vlc.table, CBPY_VLC_BITS, 1);
+
+                    if(cbpy<0){
+                        av_log(s->avctx, AV_LOG_ERROR, "P cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
+                        return -1;
+                    }
+
+                    if(s->cbp_table[xy] & 8) {
+                        ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
+                    }
+                    s->current_picture.qscale_table[xy]= s->qscale;
+
+                    s->cbp_table[xy]&= 3; //remove dquant
+                    s->cbp_table[xy]|= (cbpy^0xf)<<2;
+                }
+            }
+        }
+        if(mb_num >= mb_count) return 0;
+        s->mb_x= 0;
+    }
+    return 0;
+}
+
+/**
+ * decodes the first & second partition
+ * @return <0 if error (and sets error type in the error_status_table)
+ */
+int ff_mpeg4_decode_partitions(MpegEncContext *s)
+{
+    int mb_num;
+    const int part_a_error= s->pict_type==FF_I_TYPE ? (DC_ERROR|MV_ERROR) : MV_ERROR;
+    const int part_a_end  = s->pict_type==FF_I_TYPE ? (DC_END  |MV_END)   : MV_END;
+
+    mb_num= mpeg4_decode_partition_a(s);
+    if(mb_num<0){
+        ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, part_a_error);
+        return -1;
+    }
+
+    if(s->resync_mb_x + s->resync_mb_y*s->mb_width + mb_num > s->mb_num){
+        av_log(s->avctx, AV_LOG_ERROR, "slice below monitor ...\n");
+        ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, part_a_error);
+        return -1;
+    }
+
+    s->mb_num_left= mb_num;
+
+    if(s->pict_type==FF_I_TYPE){
+        while(show_bits(&s->gb, 9) == 1)
+            skip_bits(&s->gb, 9);
+        if(get_bits_long(&s->gb, 19)!=DC_MARKER){
+            av_log(s->avctx, AV_LOG_ERROR, "marker missing after first I partition at %d %d\n", s->mb_x, s->mb_y);
+            return -1;
+        }
+    }else{
+        while(show_bits(&s->gb, 10) == 1)
+            skip_bits(&s->gb, 10);
+        if(get_bits(&s->gb, 17)!=MOTION_MARKER){
+            av_log(s->avctx, AV_LOG_ERROR, "marker missing after first P partition at %d %d\n", s->mb_x, s->mb_y);
+            return -1;
+        }
+    }
+    ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, part_a_end);
+
+    if( mpeg4_decode_partition_b(s, mb_num) < 0){
+        if(s->pict_type==FF_P_TYPE)
+            ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, DC_ERROR);
+        return -1;
+    }else{
+        if(s->pict_type==FF_P_TYPE)
+            ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, DC_END);
+    }
+
+    return 0;
+}
+
+/**
+ * decodes a block.
+ * @return <0 if an error occurred
+ */
+static inline int mpeg4_decode_block(MpegEncContext * s, DCTELEM * block,
+                              int n, int coded, int intra, int rvlc)
+{
+    int level, i, last, run;
+    int dc_pred_dir;
+    RLTable * rl;
+    RL_VLC_ELEM * rl_vlc;
+    const uint8_t * scan_table;
+    int qmul, qadd;
+
+    //Note intra & rvlc should be optimized away if this is inlined
+
+    if(intra) {
+      if(s->use_intra_dc_vlc){
+        /* DC coef */
+        if(s->partitioned_frame){
+            level = s->dc_val[0][ s->block_index[n] ];
+            if(n<4) level= FASTDIV((level + (s->y_dc_scale>>1)), s->y_dc_scale);
+            else    level= FASTDIV((level + (s->c_dc_scale>>1)), s->c_dc_scale);
+            dc_pred_dir= (s->pred_dir_table[s->mb_x + s->mb_y*s->mb_stride]<<n)&32;
+        }else{
+            level = mpeg4_decode_dc(s, n, &dc_pred_dir);
+            if (level < 0)
+                return -1;
+        }
+        block[0] = level;
+        i = 0;
+      }else{
+            i = -1;
+            ff_mpeg4_pred_dc(s, n, 0, &dc_pred_dir, 0);
+      }
+      if (!coded)
+          goto not_coded;
+
+      if(rvlc){
+          rl = &rvlc_rl_intra;
+          rl_vlc = rvlc_rl_intra.rl_vlc[0];
+      }else{
+          rl = &rl_intra;
+          rl_vlc = rl_intra.rl_vlc[0];
+      }
+      if (s->ac_pred) {
+          if (dc_pred_dir == 0)
+              scan_table = s->intra_v_scantable.permutated; /* left */
+          else
+              scan_table = s->intra_h_scantable.permutated; /* top */
+      } else {
+            scan_table = s->intra_scantable.permutated;
+      }
+      qmul=1;
+      qadd=0;
+    } else {
+        i = -1;
+        if (!coded) {
+            s->block_last_index[n] = i;
+            return 0;
+        }
+        if(rvlc) rl = &rvlc_rl_inter;
+        else     rl = &rl_inter;
+
+        scan_table = s->intra_scantable.permutated;
+
+        if(s->mpeg_quant){
+            qmul=1;
+            qadd=0;
+            if(rvlc){
+                rl_vlc = rvlc_rl_inter.rl_vlc[0];
+            }else{
+                rl_vlc = rl_inter.rl_vlc[0];
+            }
+        }else{
+            qmul = s->qscale << 1;
+            qadd = (s->qscale - 1) | 1;
+            if(rvlc){
+                rl_vlc = rvlc_rl_inter.rl_vlc[s->qscale];
+            }else{
+                rl_vlc = rl_inter.rl_vlc[s->qscale];
+            }
+        }
+    }
+  {
+    OPEN_READER(re, &s->gb);
+    for(;;) {
+        UPDATE_CACHE(re, &s->gb);
+        GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 0);
+        if (level==0) {
+          /* escape */
+          if(rvlc){
+                if(SHOW_UBITS(re, &s->gb, 1)==0){
+                    av_log(s->avctx, AV_LOG_ERROR, "1. marker bit missing in rvlc esc\n");
+                    return -1;
+                }; SKIP_CACHE(re, &s->gb, 1);
+
+                last=  SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
+                run=   SHOW_UBITS(re, &s->gb, 6); LAST_SKIP_CACHE(re, &s->gb, 6);
+                SKIP_COUNTER(re, &s->gb, 1+1+6);
+                UPDATE_CACHE(re, &s->gb);
+
+                if(SHOW_UBITS(re, &s->gb, 1)==0){
+                    av_log(s->avctx, AV_LOG_ERROR, "2. marker bit missing in rvlc esc\n");
+                    return -1;
+                }; SKIP_CACHE(re, &s->gb, 1);
+
+                level= SHOW_UBITS(re, &s->gb, 11); SKIP_CACHE(re, &s->gb, 11);
+
+                if(SHOW_UBITS(re, &s->gb, 5)!=0x10){
+                    av_log(s->avctx, AV_LOG_ERROR, "reverse esc missing\n");
+                    return -1;
+                }; SKIP_CACHE(re, &s->gb, 5);
+
+                level=  level * qmul + qadd;
+                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1); LAST_SKIP_CACHE(re, &s->gb, 1);
+                SKIP_COUNTER(re, &s->gb, 1+11+5+1);
+
+                i+= run + 1;
+                if(last) i+=192;
+          }else{
+            int cache;
+            cache= GET_CACHE(re, &s->gb);
+
+            if(IS_3IV1)
+                cache ^= 0xC0000000;
+
+            if (cache&0x80000000) {
+                if (cache&0x40000000) {
+                    /* third escape */
+                    SKIP_CACHE(re, &s->gb, 2);
+                    last=  SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
+                    run=   SHOW_UBITS(re, &s->gb, 6); LAST_SKIP_CACHE(re, &s->gb, 6);
+                    SKIP_COUNTER(re, &s->gb, 2+1+6);
+                    UPDATE_CACHE(re, &s->gb);
+
+                    if(IS_3IV1){
+                        level= SHOW_SBITS(re, &s->gb, 12); LAST_SKIP_BITS(re, &s->gb, 12);
+                    }else{
+                        if(SHOW_UBITS(re, &s->gb, 1)==0){
+                            av_log(s->avctx, AV_LOG_ERROR, "1. marker bit missing in 3. esc\n");
+                            return -1;
+                        }; SKIP_CACHE(re, &s->gb, 1);
+
+                        level= SHOW_SBITS(re, &s->gb, 12); SKIP_CACHE(re, &s->gb, 12);
+
+                        if(SHOW_UBITS(re, &s->gb, 1)==0){
+                            av_log(s->avctx, AV_LOG_ERROR, "2. marker bit missing in 3. esc\n");
+                            return -1;
+                        }; LAST_SKIP_CACHE(re, &s->gb, 1);
+
+                        SKIP_COUNTER(re, &s->gb, 1+12+1);
+                    }
+
+#if 0
+                    if(s->error_recognition >= FF_ER_COMPLIANT){
+                        const int abs_level= FFABS(level);
+                        if(abs_level<=MAX_LEVEL && run<=MAX_RUN){
+                            const int run1= run - rl->max_run[last][abs_level] - 1;
+                            if(abs_level <= rl->max_level[last][run]){
+                                av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, vlc encoding possible\n");
+                                return -1;
+                            }
+                            if(s->error_recognition > FF_ER_COMPLIANT){
+                                if(abs_level <= rl->max_level[last][run]*2){
+                                    av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 1 encoding possible\n");
+                                    return -1;
+                                }
+                                if(run1 >= 0 && abs_level <= rl->max_level[last][run1]){
+                                    av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 2 encoding possible\n");
+                                    return -1;
+                                }
+                            }
+                        }
+                    }
+#endif
+                    if (level>0) level= level * qmul + qadd;
+                    else         level= level * qmul - qadd;
+
+                    if((unsigned)(level + 2048) > 4095){
+                        if(s->error_recognition > FF_ER_COMPLIANT){
+                            if(level > 2560 || level<-2560){
+                                av_log(s->avctx, AV_LOG_ERROR, "|level| overflow in 3. esc, qp=%d\n", s->qscale);
+                                return -1;
+                            }
+                        }
+                        level= level<0 ? -2048 : 2047;
+                    }
+
+                    i+= run + 1;
+                    if(last) i+=192;
+                } else {
+                    /* second escape */
+#if MIN_CACHE_BITS < 20
+                    LAST_SKIP_BITS(re, &s->gb, 2);
+                    UPDATE_CACHE(re, &s->gb);
+#else
+                    SKIP_BITS(re, &s->gb, 2);
+#endif
+                    GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
+                    i+= run + rl->max_run[run>>7][level/qmul] +1; //FIXME opt indexing
+                    level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
+                    LAST_SKIP_BITS(re, &s->gb, 1);
+                }
+            } else {
+                /* first escape */
+#if MIN_CACHE_BITS < 19
+                LAST_SKIP_BITS(re, &s->gb, 1);
+                UPDATE_CACHE(re, &s->gb);
+#else
+                SKIP_BITS(re, &s->gb, 1);
+#endif
+                GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
+                i+= run;
+                level = level + rl->max_level[run>>7][(run-1)&63] * qmul;//FIXME opt indexing
+                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
+                LAST_SKIP_BITS(re, &s->gb, 1);
+            }
+          }
+        } else {
+            i+= run;
+            level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
+            LAST_SKIP_BITS(re, &s->gb, 1);
+        }
+        if (i > 62){
+            i-= 192;
+            if(i&(~63)){
+                av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
+                return -1;
+            }
+
+            block[scan_table[i]] = level;
+            break;
+        }
+
+        block[scan_table[i]] = level;
+    }
+    CLOSE_READER(re, &s->gb);
+  }
+ not_coded:
+    if (intra) {
+        if(!s->use_intra_dc_vlc){
+            block[0] = ff_mpeg4_pred_dc(s, n, block[0], &dc_pred_dir, 0);
+
+            i -= i>>31; //if(i == -1) i=0;
+        }
+
+        mpeg4_pred_ac(s, block, n, dc_pred_dir);
+        if (s->ac_pred) {
+            i = 63; /* XXX: not optimal */
+        }
+    }
+    s->block_last_index[n] = i;
+    return 0;
+}
+
+/**
+ * decode partition C of one MB.
+ * @return <0 if an error occurred
+ */
+static int mpeg4_decode_partitioned_mb(MpegEncContext *s, DCTELEM block[6][64])
+{
+    int cbp, mb_type;
+    const int xy= s->mb_x + s->mb_y*s->mb_stride;
+
+    mb_type= s->current_picture.mb_type[xy];
+    cbp = s->cbp_table[xy];
+
+    s->use_intra_dc_vlc= s->qscale < s->intra_dc_threshold;
+
+    if(s->current_picture.qscale_table[xy] != s->qscale){
+        ff_set_qscale(s, s->current_picture.qscale_table[xy] );
+    }
+
+    if (s->pict_type == FF_P_TYPE || s->pict_type==FF_S_TYPE) {
+        int i;
+        for(i=0; i<4; i++){
+            s->mv[0][i][0] = s->current_picture.motion_val[0][ s->block_index[i] ][0];
+            s->mv[0][i][1] = s->current_picture.motion_val[0][ s->block_index[i] ][1];
+        }
+        s->mb_intra = IS_INTRA(mb_type);
+
+        if (IS_SKIP(mb_type)) {
+            /* skip mb */
+            for(i=0;i<6;i++)
+                s->block_last_index[i] = -1;
+            s->mv_dir = MV_DIR_FORWARD;
+            s->mv_type = MV_TYPE_16X16;
+            if(s->pict_type==FF_S_TYPE && s->vol_sprite_usage==GMC_SPRITE){
+                s->mcsel=1;
+                s->mb_skipped = 0;
+            }else{
+                s->mcsel=0;
+                s->mb_skipped = 1;
+            }
+        }else if(s->mb_intra){
+            s->ac_pred = IS_ACPRED(s->current_picture.mb_type[xy]);
+        }else if(!s->mb_intra){
+//            s->mcsel= 0; //FIXME do we need to init that
+
+            s->mv_dir = MV_DIR_FORWARD;
+            if (IS_8X8(mb_type)) {
+                s->mv_type = MV_TYPE_8X8;
+            } else {
+                s->mv_type = MV_TYPE_16X16;
+            }
+        }
+    } else { /* I-Frame */
+        s->mb_intra = 1;
+        s->ac_pred = IS_ACPRED(s->current_picture.mb_type[xy]);
+    }
+
+    if (!IS_SKIP(mb_type)) {
+        int i;
+        s->dsp.clear_blocks(s->block[0]);
+        /* decode each block */
+        for (i = 0; i < 6; i++) {
+            if(mpeg4_decode_block(s, block[i], i, cbp&32, s->mb_intra, s->rvlc) < 0){
+                av_log(s->avctx, AV_LOG_ERROR, "texture corrupted at %d %d %d\n", s->mb_x, s->mb_y, s->mb_intra);
+                return -1;
+            }
+            cbp+=cbp;
+        }
+    }
+
+    /* per-MB end of slice check */
+
+    if(--s->mb_num_left <= 0){
+        if(mpeg4_is_resync(s))
+            return SLICE_END;
+        else
+            return SLICE_NOEND;
+    }else{
+        if(mpeg4_is_resync(s)){
+            const int delta= s->mb_x + 1 == s->mb_width ? 2 : 1;
+            if(s->cbp_table[xy+delta])
+                return SLICE_END;
+        }
+        return SLICE_OK;
+    }
+}
+
+static int mpeg4_decode_mb(MpegEncContext *s,
+                      DCTELEM block[6][64])
+{
+    int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant;
+    int16_t *mot_val;
+    static int8_t quant_tab[4] = { -1, -2, 1, 2 };
+    const int xy= s->mb_x + s->mb_y * s->mb_stride;
+
+    assert(s->h263_pred);
+
+    if (s->pict_type == FF_P_TYPE || s->pict_type==FF_S_TYPE) {
+        do{
+            if (get_bits1(&s->gb)) {
+                /* skip mb */
+                s->mb_intra = 0;
+                for(i=0;i<6;i++)
+                    s->block_last_index[i] = -1;
+                s->mv_dir = MV_DIR_FORWARD;
+                s->mv_type = MV_TYPE_16X16;
+                if(s->pict_type==FF_S_TYPE && s->vol_sprite_usage==GMC_SPRITE){
+                    s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_GMC | MB_TYPE_16x16 | MB_TYPE_L0;
+                    s->mcsel=1;
+                    s->mv[0][0][0]= get_amv(s, 0);
+                    s->mv[0][0][1]= get_amv(s, 1);
+
+                    s->mb_skipped = 0;
+                }else{
+                    s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
+                    s->mcsel=0;
+                    s->mv[0][0][0] = 0;
+                    s->mv[0][0][1] = 0;
+                    s->mb_skipped = 1;
+                }
+                goto end;
+            }
+            cbpc = get_vlc2(&s->gb, inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
+            if (cbpc < 0){
+                av_log(s->avctx, AV_LOG_ERROR, "cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
+                return -1;
+            }
+        }while(cbpc == 20);
+
+        s->dsp.clear_blocks(s->block[0]);
+        dquant = cbpc & 8;
+        s->mb_intra = ((cbpc & 4) != 0);
+        if (s->mb_intra) goto intra;
+
+        if(s->pict_type==FF_S_TYPE && s->vol_sprite_usage==GMC_SPRITE && (cbpc & 16) == 0)
+            s->mcsel= get_bits1(&s->gb);
+        else s->mcsel= 0;
+        cbpy = get_vlc2(&s->gb, cbpy_vlc.table, CBPY_VLC_BITS, 1) ^ 0x0F;
+
+        cbp = (cbpc & 3) | (cbpy << 2);
+        if (dquant) {
+            ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
+        }
+        if((!s->progressive_sequence) && (cbp || (s->workaround_bugs&FF_BUG_XVID_ILACE)))
+            s->interlaced_dct= get_bits1(&s->gb);
+
+        s->mv_dir = MV_DIR_FORWARD;
+        if ((cbpc & 16) == 0) {
+            if(s->mcsel){
+                s->current_picture.mb_type[xy]= MB_TYPE_GMC | MB_TYPE_16x16 | MB_TYPE_L0;
+                /* 16x16 global motion prediction */
+                s->mv_type = MV_TYPE_16X16;
+                mx= get_amv(s, 0);
+                my= get_amv(s, 1);
+                s->mv[0][0][0] = mx;
+                s->mv[0][0][1] = my;
+            }else if((!s->progressive_sequence) && get_bits1(&s->gb)){
+                s->current_picture.mb_type[xy]= MB_TYPE_16x8 | MB_TYPE_L0 | MB_TYPE_INTERLACED;
+                /* 16x8 field motion prediction */
+                s->mv_type= MV_TYPE_FIELD;
+
+                s->field_select[0][0]= get_bits1(&s->gb);
+                s->field_select[0][1]= get_bits1(&s->gb);
+
+                h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
+
+                for(i=0; i<2; i++){
+                    mx = h263_decode_motion(s, pred_x, s->f_code);
+                    if (mx >= 0xffff)
+                        return -1;
+
+                    my = h263_decode_motion(s, pred_y/2, s->f_code);
+                    if (my >= 0xffff)
+                        return -1;
+
+                    s->mv[0][i][0] = mx;
+                    s->mv[0][i][1] = my;
+                }
+            }else{
+                s->current_picture.mb_type[xy]= MB_TYPE_16x16 | MB_TYPE_L0;
+                /* 16x16 motion prediction */
+                s->mv_type = MV_TYPE_16X16;
+                h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
+                mx = h263_decode_motion(s, pred_x, s->f_code);
+
+                if (mx >= 0xffff)
+                    return -1;
+
+                my = h263_decode_motion(s, pred_y, s->f_code);
+
+                if (my >= 0xffff)
+                    return -1;
+                s->mv[0][0][0] = mx;
+                s->mv[0][0][1] = my;
+            }
+        } else {
+            s->current_picture.mb_type[xy]= MB_TYPE_8x8 | MB_TYPE_L0;
+            s->mv_type = MV_TYPE_8X8;
+            for(i=0;i<4;i++) {
+                mot_val = h263_pred_motion(s, i, 0, &pred_x, &pred_y);
+                mx = h263_decode_motion(s, pred_x, s->f_code);
+                if (mx >= 0xffff)
+                    return -1;
+
+                my = h263_decode_motion(s, pred_y, s->f_code);
+                if (my >= 0xffff)
+                    return -1;
+                s->mv[0][i][0] = mx;
+                s->mv[0][i][1] = my;
+                mot_val[0] = mx;
+                mot_val[1] = my;
+            }
+        }
+    } else if(s->pict_type==FF_B_TYPE) {
+        int modb1; // first bit of modb
+        int modb2; // second bit of modb
+        int mb_type;
+
+        s->mb_intra = 0; //B-frames never contain intra blocks
+        s->mcsel=0;      //     ...               true gmc blocks
+
+        if(s->mb_x==0){
+            for(i=0; i<2; i++){
+                s->last_mv[i][0][0]=
+                s->last_mv[i][0][1]=
+                s->last_mv[i][1][0]=
+                s->last_mv[i][1][1]= 0;
+            }
+        }
+
+        /* if we skipped it in the future P Frame than skip it now too */
+        s->mb_skipped= s->next_picture.mbskip_table[s->mb_y * s->mb_stride + s->mb_x]; // Note, skiptab=0 if last was GMC
+
+        if(s->mb_skipped){
+                /* skip mb */
+            for(i=0;i<6;i++)
+                s->block_last_index[i] = -1;
+
+            s->mv_dir = MV_DIR_FORWARD;
+            s->mv_type = MV_TYPE_16X16;
+            s->mv[0][0][0] = 0;
+            s->mv[0][0][1] = 0;
+            s->mv[1][0][0] = 0;
+            s->mv[1][0][1] = 0;
+            s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
+            goto end;
+        }
+
+        modb1= get_bits1(&s->gb);
+        if(modb1){
+            mb_type= MB_TYPE_DIRECT2 | MB_TYPE_SKIP | MB_TYPE_L0L1; //like MB_TYPE_B_DIRECT but no vectors coded
+            cbp=0;
+        }else{
+            modb2= get_bits1(&s->gb);
+            mb_type= get_vlc2(&s->gb, mb_type_b_vlc.table, MB_TYPE_B_VLC_BITS, 1);
+            if(mb_type<0){
+                av_log(s->avctx, AV_LOG_ERROR, "illegal MB_type\n");
+                return -1;
+            }
+            mb_type= mb_type_b_map[ mb_type ];
+            if(modb2) cbp= 0;
+            else{
+                s->dsp.clear_blocks(s->block[0]);
+                cbp= get_bits(&s->gb, 6);
+            }
+
+            if ((!IS_DIRECT(mb_type)) && cbp) {
+                if(get_bits1(&s->gb)){
+                    ff_set_qscale(s, s->qscale + get_bits1(&s->gb)*4 - 2);
+                }
+            }
+
+            if(!s->progressive_sequence){
+                if(cbp)
+                    s->interlaced_dct= get_bits1(&s->gb);
+
+                if(!IS_DIRECT(mb_type) && get_bits1(&s->gb)){
+                    mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
+                    mb_type &= ~MB_TYPE_16x16;
+
+                    if(USES_LIST(mb_type, 0)){
+                        s->field_select[0][0]= get_bits1(&s->gb);
+                        s->field_select[0][1]= get_bits1(&s->gb);
+                    }
+                    if(USES_LIST(mb_type, 1)){
+                        s->field_select[1][0]= get_bits1(&s->gb);
+                        s->field_select[1][1]= get_bits1(&s->gb);
+                    }
+                }
+            }
+
+            s->mv_dir = 0;
+            if((mb_type & (MB_TYPE_DIRECT2|MB_TYPE_INTERLACED)) == 0){
+                s->mv_type= MV_TYPE_16X16;
+
+                if(USES_LIST(mb_type, 0)){
+                    s->mv_dir = MV_DIR_FORWARD;
+
+                    mx = h263_decode_motion(s, s->last_mv[0][0][0], s->f_code);
+                    my = h263_decode_motion(s, s->last_mv[0][0][1], s->f_code);
+                    s->last_mv[0][1][0]= s->last_mv[0][0][0]= s->mv[0][0][0] = mx;
+                    s->last_mv[0][1][1]= s->last_mv[0][0][1]= s->mv[0][0][1] = my;
+                }
+
+                if(USES_LIST(mb_type, 1)){
+                    s->mv_dir |= MV_DIR_BACKWARD;
+
+                    mx = h263_decode_motion(s, s->last_mv[1][0][0], s->b_code);
+                    my = h263_decode_motion(s, s->last_mv[1][0][1], s->b_code);
+                    s->last_mv[1][1][0]= s->last_mv[1][0][0]= s->mv[1][0][0] = mx;
+                    s->last_mv[1][1][1]= s->last_mv[1][0][1]= s->mv[1][0][1] = my;
+                }
+            }else if(!IS_DIRECT(mb_type)){
+                s->mv_type= MV_TYPE_FIELD;
+
+                if(USES_LIST(mb_type, 0)){
+                    s->mv_dir = MV_DIR_FORWARD;
+
+                    for(i=0; i<2; i++){
+                        mx = h263_decode_motion(s, s->last_mv[0][i][0]  , s->f_code);
+                        my = h263_decode_motion(s, s->last_mv[0][i][1]/2, s->f_code);
+                        s->last_mv[0][i][0]=  s->mv[0][i][0] = mx;
+                        s->last_mv[0][i][1]= (s->mv[0][i][1] = my)*2;
+                    }
+                }
+
+                if(USES_LIST(mb_type, 1)){
+                    s->mv_dir |= MV_DIR_BACKWARD;
+
+                    for(i=0; i<2; i++){
+                        mx = h263_decode_motion(s, s->last_mv[1][i][0]  , s->b_code);
+                        my = h263_decode_motion(s, s->last_mv[1][i][1]/2, s->b_code);
+                        s->last_mv[1][i][0]=  s->mv[1][i][0] = mx;
+                        s->last_mv[1][i][1]= (s->mv[1][i][1] = my)*2;
+                    }
+                }
+            }
+        }
+
+        if(IS_DIRECT(mb_type)){
+            if(IS_SKIP(mb_type))
+                mx=my=0;
+            else{
+                mx = h263_decode_motion(s, 0, 1);
+                my = h263_decode_motion(s, 0, 1);
+            }
+
+            s->mv_dir = MV_DIR_FORWARD | MV_DIR_BACKWARD | MV_DIRECT;
+            mb_type |= ff_mpeg4_set_direct_mv(s, mx, my);
+        }
+        s->current_picture.mb_type[xy]= mb_type;
+    } else { /* I-Frame */
+        do{
+            cbpc = get_vlc2(&s->gb, intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
+            if (cbpc < 0){
+                av_log(s->avctx, AV_LOG_ERROR, "I cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
+                return -1;
+            }
+        }while(cbpc == 8);
+
+        dquant = cbpc & 4;
+        s->mb_intra = 1;
+intra:
+        s->ac_pred = get_bits1(&s->gb);
+        if(s->ac_pred)
+            s->current_picture.mb_type[xy]= MB_TYPE_INTRA | MB_TYPE_ACPRED;
+        else
+            s->current_picture.mb_type[xy]= MB_TYPE_INTRA;
+
+        cbpy = get_vlc2(&s->gb, cbpy_vlc.table, CBPY_VLC_BITS, 1);
+        if(cbpy<0){
+            av_log(s->avctx, AV_LOG_ERROR, "I cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
+            return -1;
+        }
+        cbp = (cbpc & 3) | (cbpy << 2);
+
+        s->use_intra_dc_vlc= s->qscale < s->intra_dc_threshold;
+
+        if (dquant) {
+            ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
+        }
+
+        if(!s->progressive_sequence)
+            s->interlaced_dct= get_bits1(&s->gb);
+
+        s->dsp.clear_blocks(s->block[0]);
+        /* decode each block */
+        for (i = 0; i < 6; i++) {
+            if (mpeg4_decode_block(s, block[i], i, cbp&32, 1, 0) < 0)
+                return -1;
+            cbp+=cbp;
+        }
+        goto end;
+    }
+
+    /* decode each block */
+    for (i = 0; i < 6; i++) {
+        if (mpeg4_decode_block(s, block[i], i, cbp&32, 0, 0) < 0)
+            return -1;
+        cbp+=cbp;
+    }
+end:
+
+        /* per-MB end of slice check */
+    if(s->codec_id==CODEC_ID_MPEG4){
+        if(mpeg4_is_resync(s)){
+            const int delta= s->mb_x + 1 == s->mb_width ? 2 : 1;
+            if(s->pict_type==FF_B_TYPE && s->next_picture.mbskip_table[xy + delta])
+                return SLICE_OK;
+            return SLICE_END;
+        }
+    }
+
+    return SLICE_OK;
+}
+
+
+static int mpeg4_decode_gop_header(MpegEncContext * s, GetBitContext *gb){
+    int hours, minutes, seconds;
+
+    hours= get_bits(gb, 5);
+    minutes= get_bits(gb, 6);
+    skip_bits1(gb);
+    seconds= get_bits(gb, 6);
+
+    s->time_base= seconds + 60*(minutes + 60*hours);
+
+    skip_bits1(gb);
+    skip_bits1(gb);
+
+    return 0;
+}
+
+static int decode_vol_header(MpegEncContext *s, GetBitContext *gb){
+    int width, height, vo_ver_id;
+
+    /* vol header */
+    skip_bits(gb, 1); /* random access */
+    s->vo_type= get_bits(gb, 8);
+    if (get_bits1(gb) != 0) { /* is_ol_id */
+        vo_ver_id = get_bits(gb, 4); /* vo_ver_id */
+        skip_bits(gb, 3); /* vo_priority */
+    } else {
+        vo_ver_id = 1;
+    }
+    s->aspect_ratio_info= get_bits(gb, 4);
+    if(s->aspect_ratio_info == FF_ASPECT_EXTENDED){
+        s->avctx->sample_aspect_ratio.num= get_bits(gb, 8); // par_width
+        s->avctx->sample_aspect_ratio.den= get_bits(gb, 8); // par_height
+    }else{
+        s->avctx->sample_aspect_ratio= ff_h263_pixel_aspect[s->aspect_ratio_info];
+    }
+
+    if ((s->vol_control_parameters=get_bits1(gb))) { /* vol control parameter */
+        int chroma_format= get_bits(gb, 2);
+        if(chroma_format!=CHROMA_420){
+            av_log(s->avctx, AV_LOG_ERROR, "illegal chroma format\n");
+        }
+        s->low_delay= get_bits1(gb);
+        if(get_bits1(gb)){ /* vbv parameters */
+            get_bits(gb, 15);   /* first_half_bitrate */
+            skip_bits1(gb);     /* marker */
+            get_bits(gb, 15);   /* latter_half_bitrate */
+            skip_bits1(gb);     /* marker */
+            get_bits(gb, 15);   /* first_half_vbv_buffer_size */
+            skip_bits1(gb);     /* marker */
+            get_bits(gb, 3);    /* latter_half_vbv_buffer_size */
+            get_bits(gb, 11);   /* first_half_vbv_occupancy */
+            skip_bits1(gb);     /* marker */
+            get_bits(gb, 15);   /* latter_half_vbv_occupancy */
+            skip_bits1(gb);     /* marker */
+        }
+    }else{
+        // set low delay flag only once the smartest? low delay detection won't be overriden
+        if(s->picture_number==0)
+            s->low_delay=0;
+    }
+
+    s->shape = get_bits(gb, 2); /* vol shape */
+    if(s->shape != RECT_SHAPE) av_log(s->avctx, AV_LOG_ERROR, "only rectangular vol supported\n");
+    if(s->shape == GRAY_SHAPE && vo_ver_id != 1){
+        av_log(s->avctx, AV_LOG_ERROR, "Gray shape not supported\n");
+        skip_bits(gb, 4);  //video_object_layer_shape_extension
+    }
+
+    check_marker(gb, "before time_increment_resolution");
+
+    s->avctx->time_base.den = get_bits(gb, 16);
+    if(!s->avctx->time_base.den){
+        av_log(s->avctx, AV_LOG_ERROR, "time_base.den==0\n");
+        return -1;
+    }
+
+    s->time_increment_bits = av_log2(s->avctx->time_base.den - 1) + 1;
+    if (s->time_increment_bits < 1)
+        s->time_increment_bits = 1;
+
+    check_marker(gb, "before fixed_vop_rate");
+
+    if (get_bits1(gb) != 0) {   /* fixed_vop_rate  */
+        s->avctx->time_base.num = get_bits(gb, s->time_increment_bits);
+    }else
+        s->avctx->time_base.num = 1;
+
+    s->t_frame=0;
+
+    if (s->shape != BIN_ONLY_SHAPE) {
+        if (s->shape == RECT_SHAPE) {
+            skip_bits1(gb);   /* marker */
+            width = get_bits(gb, 13);
+            skip_bits1(gb);   /* marker */
+            height = get_bits(gb, 13);
+            skip_bits1(gb);   /* marker */
+            if(width && height && !(s->width && s->codec_tag == AV_RL32("MP4S"))){ /* they should be non zero but who knows ... */
+                s->width = width;
+                s->height = height;
+            }
+        }
+
+        s->progressive_sequence=
+        s->progressive_frame= get_bits1(gb)^1;
+        s->interlaced_dct=0;
+        if(!get_bits1(gb) && (s->avctx->debug & FF_DEBUG_PICT_INFO))
+            av_log(s->avctx, AV_LOG_INFO, "MPEG4 OBMC not supported (very likely buggy encoder)\n");   /* OBMC Disable */
+        if (vo_ver_id == 1) {
+            s->vol_sprite_usage = get_bits1(gb); /* vol_sprite_usage */
+        } else {
+            s->vol_sprite_usage = get_bits(gb, 2); /* vol_sprite_usage */
+        }
+        if(s->vol_sprite_usage==STATIC_SPRITE) av_log(s->avctx, AV_LOG_ERROR, "Static Sprites not supported\n");
+        if(s->vol_sprite_usage==STATIC_SPRITE || s->vol_sprite_usage==GMC_SPRITE){
+            if(s->vol_sprite_usage==STATIC_SPRITE){
+                s->sprite_width = get_bits(gb, 13);
+                skip_bits1(gb); /* marker */
+                s->sprite_height= get_bits(gb, 13);
+                skip_bits1(gb); /* marker */
+                s->sprite_left  = get_bits(gb, 13);
+                skip_bits1(gb); /* marker */
+                s->sprite_top   = get_bits(gb, 13);
+                skip_bits1(gb); /* marker */
+            }
+            s->num_sprite_warping_points= get_bits(gb, 6);
+            if(s->num_sprite_warping_points > 3){
+                av_log(s->avctx, AV_LOG_ERROR, "%d sprite_warping_points\n", s->num_sprite_warping_points);
+                s->num_sprite_warping_points= 0;
+                return -1;
+            }
+            s->sprite_warping_accuracy = get_bits(gb, 2);
+            s->sprite_brightness_change= get_bits1(gb);
+            if(s->vol_sprite_usage==STATIC_SPRITE)
+                s->low_latency_sprite= get_bits1(gb);
+        }
+        // FIXME sadct disable bit if verid!=1 && shape not rect
+
+        if (get_bits1(gb) == 1) {   /* not_8_bit */
+            s->quant_precision = get_bits(gb, 4); /* quant_precision */
+            if(get_bits(gb, 4)!=8) av_log(s->avctx, AV_LOG_ERROR, "N-bit not supported\n"); /* bits_per_pixel */
+            if(s->quant_precision!=5) av_log(s->avctx, AV_LOG_ERROR, "quant precision %d\n", s->quant_precision);
+        } else {
+            s->quant_precision = 5;
+        }
+
+        // FIXME a bunch of grayscale shape things
+
+        if((s->mpeg_quant=get_bits1(gb))){ /* vol_quant_type */
+            int i, v;
+
+            /* load default matrixes */
+            for(i=0; i<64; i++){
+                int j= s->dsp.idct_permutation[i];
+                v= ff_mpeg4_default_intra_matrix[i];
+                s->intra_matrix[j]= v;
+                s->chroma_intra_matrix[j]= v;
+
+                v= ff_mpeg4_default_non_intra_matrix[i];
+                s->inter_matrix[j]= v;
+                s->chroma_inter_matrix[j]= v;
+            }
+
+            /* load custom intra matrix */
+            if(get_bits1(gb)){
+                int last=0;
+                for(i=0; i<64; i++){
+                    int j;
+                    v= get_bits(gb, 8);
+                    if(v==0) break;
+
+                    last= v;
+                    j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
+                    s->intra_matrix[j]= v;
+                    s->chroma_intra_matrix[j]= v;
+                }
+
+                /* replicate last value */
+                for(; i<64; i++){
+                    int j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
+                    s->intra_matrix[j]= last;
+                    s->chroma_intra_matrix[j]= last;
+                }
+            }
+
+            /* load custom non intra matrix */
+            if(get_bits1(gb)){
+                int last=0;
+                for(i=0; i<64; i++){
+                    int j;
+                    v= get_bits(gb, 8);
+                    if(v==0) break;
+
+                    last= v;
+                    j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
+                    s->inter_matrix[j]= v;
+                    s->chroma_inter_matrix[j]= v;
+                }
+
+                /* replicate last value */
+                for(; i<64; i++){
+                    int j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
+                    s->inter_matrix[j]= last;
+                    s->chroma_inter_matrix[j]= last;
+                }
+            }
+
+            // FIXME a bunch of grayscale shape things
+        }
+
+        if(vo_ver_id != 1)
+             s->quarter_sample= get_bits1(gb);
+        else s->quarter_sample=0;
+
+        if(!get_bits1(gb)){
+            int pos= get_bits_count(gb);
+            int estimation_method= get_bits(gb, 2);
+            if(estimation_method<2){
+                if(!get_bits1(gb)){
+                    s->cplx_estimation_trash_i += 8*get_bits1(gb); //opaque
+                    s->cplx_estimation_trash_i += 8*get_bits1(gb); //transparent
+                    s->cplx_estimation_trash_i += 8*get_bits1(gb); //intra_cae
+                    s->cplx_estimation_trash_i += 8*get_bits1(gb); //inter_cae
+                    s->cplx_estimation_trash_i += 8*get_bits1(gb); //no_update
+                    s->cplx_estimation_trash_i += 8*get_bits1(gb); //upampling
+                }
+                if(!get_bits1(gb)){
+                    s->cplx_estimation_trash_i += 8*get_bits1(gb); //intra_blocks
+                    s->cplx_estimation_trash_p += 8*get_bits1(gb); //inter_blocks
+                    s->cplx_estimation_trash_p += 8*get_bits1(gb); //inter4v_blocks
+                    s->cplx_estimation_trash_i += 8*get_bits1(gb); //not coded blocks
+                }
+                if(!check_marker(gb, "in complexity estimation part 1")){
+                    skip_bits_long(gb, pos - get_bits_count(gb));
+                    goto no_cplx_est;
+                }
+                if(!get_bits1(gb)){
+                    s->cplx_estimation_trash_i += 8*get_bits1(gb); //dct_coeffs
+                    s->cplx_estimation_trash_i += 8*get_bits1(gb); //dct_lines
+                    s->cplx_estimation_trash_i += 8*get_bits1(gb); //vlc_syms
+                    s->cplx_estimation_trash_i += 4*get_bits1(gb); //vlc_bits
+                }
+                if(!get_bits1(gb)){
+                    s->cplx_estimation_trash_p += 8*get_bits1(gb); //apm
+                    s->cplx_estimation_trash_p += 8*get_bits1(gb); //npm
+                    s->cplx_estimation_trash_b += 8*get_bits1(gb); //interpolate_mc_q
+                    s->cplx_estimation_trash_p += 8*get_bits1(gb); //forwback_mc_q
+                    s->cplx_estimation_trash_p += 8*get_bits1(gb); //halfpel2
+                    s->cplx_estimation_trash_p += 8*get_bits1(gb); //halfpel4
+                }
+                if(!check_marker(gb, "in complexity estimation part 2")){
+                    skip_bits_long(gb, pos - get_bits_count(gb));
+                    goto no_cplx_est;
+                }
+                if(estimation_method==1){
+                    s->cplx_estimation_trash_i += 8*get_bits1(gb); //sadct
+                    s->cplx_estimation_trash_p += 8*get_bits1(gb); //qpel
+                }
+            }else
+                av_log(s->avctx, AV_LOG_ERROR, "Invalid Complexity estimation method %d\n", estimation_method);
+        }else{
+no_cplx_est:
+            s->cplx_estimation_trash_i=
+            s->cplx_estimation_trash_p=
+            s->cplx_estimation_trash_b= 0;
+        }
+
+        s->resync_marker= !get_bits1(gb); /* resync_marker_disabled */
+
+        s->data_partitioning= get_bits1(gb);
+        if(s->data_partitioning){
+            s->rvlc= get_bits1(gb);
+        }
+
+        if(vo_ver_id != 1) {
+            s->new_pred= get_bits1(gb);
+            if(s->new_pred){
+                av_log(s->avctx, AV_LOG_ERROR, "new pred not supported\n");
+                skip_bits(gb, 2); /* requested upstream message type */
+                skip_bits1(gb); /* newpred segment type */
+            }
+            s->reduced_res_vop= get_bits1(gb);
+            if(s->reduced_res_vop) av_log(s->avctx, AV_LOG_ERROR, "reduced resolution VOP not supported\n");
+        }
+        else{
+            s->new_pred=0;
+            s->reduced_res_vop= 0;
+        }
+
+        s->scalability= get_bits1(gb);
+
+        if (s->scalability) {
+            GetBitContext bak= *gb;
+            int ref_layer_id;
+            int ref_layer_sampling_dir;
+            int h_sampling_factor_n;
+            int h_sampling_factor_m;
+            int v_sampling_factor_n;
+            int v_sampling_factor_m;
+
+            s->hierachy_type= get_bits1(gb);
+            ref_layer_id= get_bits(gb, 4);
+            ref_layer_sampling_dir= get_bits1(gb);
+            h_sampling_factor_n= get_bits(gb, 5);
+            h_sampling_factor_m= get_bits(gb, 5);
+            v_sampling_factor_n= get_bits(gb, 5);
+            v_sampling_factor_m= get_bits(gb, 5);
+            s->enhancement_type= get_bits1(gb);
+
+            if(   h_sampling_factor_n==0 || h_sampling_factor_m==0
+               || v_sampling_factor_n==0 || v_sampling_factor_m==0){
+                /* illegal scalability header (VERY broken encoder),
+                 * trying to workaround */
+                s->scalability=0;
+                *gb= bak;
+            }else
+                av_log(s->avctx, AV_LOG_ERROR, "scalability not supported\n");
+
+            // bin shape stuff FIXME
+        }
+    }
+    return 0;
+}
+
+/**
+ * decodes the user data stuff in the header.
+ * Also initializes divx/xvid/lavc_version/build.
+ */
+static int decode_user_data(MpegEncContext *s, GetBitContext *gb){
+    char buf[256];
+    int i;
+    int e;
+    int ver = 0, build = 0, ver2 = 0, ver3 = 0;
+    char last;
+
+    for(i=0; i<255 && get_bits_count(gb) < gb->size_in_bits; i++){
+        if(show_bits(gb, 23) == 0) break;
+        buf[i]= get_bits(gb, 8);
+    }
+    buf[i]=0;
+
+    /* divx detection */
+    e=sscanf(buf, "DivX%dBuild%d%c", &ver, &build, &last);
+    if(e<2)
+        e=sscanf(buf, "DivX%db%d%c", &ver, &build, &last);
+    if(e>=2){
+        s->divx_version= ver;
+        s->divx_build= build;
+        s->divx_packed= e==3 && last=='p';
+        if(s->divx_packed && !s->showed_packed_warning) {
+            av_log(s->avctx, AV_LOG_WARNING, "Invalid and inefficient vfw-avi packed B frames detected\n");
+            s->showed_packed_warning=1;
+        }
+    }
+
+    /* ffmpeg detection */
+    e=sscanf(buf, "FFmpe%*[^b]b%d", &build)+3;
+    if(e!=4)
+        e=sscanf(buf, "FFmpeg v%d.%d.%d / libavcodec build: %d", &ver, &ver2, &ver3, &build);
+    if(e!=4){
+        e=sscanf(buf, "Lavc%d.%d.%d", &ver, &ver2, &ver3)+1;
+        if (e>1)
+            build= (ver<<16) + (ver2<<8) + ver3;
+    }
+    if(e!=4){
+        if(strcmp(buf, "ffmpeg")==0){
+            s->lavc_build= 4600;
+        }
+    }
+    if(e==4){
+        s->lavc_build= build;
+    }
+
+    /* Xvid detection */
+    e=sscanf(buf, "XviD%d", &build);
+    if(e==1){
+        s->xvid_build= build;
+    }
+
+    return 0;
+}
+
+static int decode_vop_header(MpegEncContext *s, GetBitContext *gb){
+    int time_incr, time_increment;
+
+    s->pict_type = get_bits(gb, 2) + FF_I_TYPE;        /* pict type: I = 0 , P = 1 */
+    if(s->pict_type==FF_B_TYPE && s->low_delay && s->vol_control_parameters==0 && !(s->flags & CODEC_FLAG_LOW_DELAY)){
+        av_log(s->avctx, AV_LOG_ERROR, "low_delay flag incorrectly, clearing it\n");
+        s->low_delay=0;
+    }
+
+    s->partitioned_frame= s->data_partitioning && s->pict_type!=FF_B_TYPE;
+    if(s->partitioned_frame)
+        s->decode_mb= mpeg4_decode_partitioned_mb;
+    else
+        s->decode_mb= mpeg4_decode_mb;
+
+    time_incr=0;
+    while (get_bits1(gb) != 0)
+        time_incr++;
+
+    check_marker(gb, "before time_increment");
+
+    if(s->time_increment_bits==0 || !(show_bits(gb, s->time_increment_bits+1)&1)){
+        av_log(s->avctx, AV_LOG_ERROR, "hmm, seems the headers are not complete, trying to guess time_increment_bits\n");
+
+        for(s->time_increment_bits=1 ;s->time_increment_bits<16; s->time_increment_bits++){
+            if (    s->pict_type == FF_P_TYPE
+                || (s->pict_type == FF_S_TYPE && s->vol_sprite_usage==GMC_SPRITE)) {
+                if((show_bits(gb, s->time_increment_bits+6)&0x37) == 0x30) break;
+            }else
+                if((show_bits(gb, s->time_increment_bits+5)&0x1F) == 0x18) break;
+        }
+
+        av_log(s->avctx, AV_LOG_ERROR, "my guess is %d bits ;)\n",s->time_increment_bits);
+    }
+
+    if(IS_3IV1) time_increment= get_bits1(gb); //FIXME investigate further
+    else time_increment= get_bits(gb, s->time_increment_bits);
+
+    if(s->pict_type!=FF_B_TYPE){
+        s->last_time_base= s->time_base;
+        s->time_base+= time_incr;
+        s->time= s->time_base*s->avctx->time_base.den + time_increment;
+        if(s->workaround_bugs&FF_BUG_UMP4){
+            if(s->time < s->last_non_b_time){
+                /* header is not mpeg-4-compatible, broken encoder,
+                 * trying to workaround */
+                s->time_base++;
+                s->time+= s->avctx->time_base.den;
+            }
+        }
+        s->pp_time= s->time - s->last_non_b_time;
+        s->last_non_b_time= s->time;
+    }else{
+        s->time= (s->last_time_base + time_incr)*s->avctx->time_base.den + time_increment;
+        s->pb_time= s->pp_time - (s->last_non_b_time - s->time);
+        if(s->pp_time <=s->pb_time || s->pp_time <= s->pp_time - s->pb_time || s->pp_time<=0){
+            /* messed up order, maybe after seeking? skipping current b-frame */
+            return FRAME_SKIPPED;
+        }
+        ff_mpeg4_init_direct_mv(s);
+
+        if(s->t_frame==0) s->t_frame= s->pb_time;
+        if(s->t_frame==0) s->t_frame=1; // 1/0 protection
+        s->pp_field_time= (  ROUNDED_DIV(s->last_non_b_time, s->t_frame)
+                           - ROUNDED_DIV(s->last_non_b_time - s->pp_time, s->t_frame))*2;
+        s->pb_field_time= (  ROUNDED_DIV(s->time, s->t_frame)
+                           - ROUNDED_DIV(s->last_non_b_time - s->pp_time, s->t_frame))*2;
+        if(!s->progressive_sequence){
+            if(s->pp_field_time <= s->pb_field_time || s->pb_field_time <= 1)
+                return FRAME_SKIPPED;
+        }
+    }
+
+    if(s->avctx->time_base.num)
+        s->current_picture_ptr->pts= (s->time + s->avctx->time_base.num/2) / s->avctx->time_base.num;
+    else
+        s->current_picture_ptr->pts= AV_NOPTS_VALUE;
+    if(s->avctx->debug&FF_DEBUG_PTS)
+        av_log(s->avctx, AV_LOG_DEBUG, "MPEG4 PTS: %"PRId64"\n", s->current_picture_ptr->pts);
+
+    check_marker(gb, "before vop_coded");
+
+    /* vop coded */
+    if (get_bits1(gb) != 1){
+        if(s->avctx->debug&FF_DEBUG_PICT_INFO)
+            av_log(s->avctx, AV_LOG_ERROR, "vop not coded\n");
+        return FRAME_SKIPPED;
+    }
+    if (s->shape != BIN_ONLY_SHAPE && ( s->pict_type == FF_P_TYPE
+                          || (s->pict_type == FF_S_TYPE && s->vol_sprite_usage==GMC_SPRITE))) {
+        /* rounding type for motion estimation */
+        s->no_rounding = get_bits1(gb);
+    } else {
+        s->no_rounding = 0;
+    }
+//FIXME reduced res stuff
+
+     if (s->shape != RECT_SHAPE) {
+         if (s->vol_sprite_usage != 1 || s->pict_type != FF_I_TYPE) {
+             int width, height, hor_spat_ref, ver_spat_ref;
+
+             width = get_bits(gb, 13);
+             skip_bits1(gb);   /* marker */
+             height = get_bits(gb, 13);
+             skip_bits1(gb);   /* marker */
+             hor_spat_ref = get_bits(gb, 13); /* hor_spat_ref */
+             skip_bits1(gb);   /* marker */
+             ver_spat_ref = get_bits(gb, 13); /* ver_spat_ref */
+         }
+         skip_bits1(gb); /* change_CR_disable */
+
+         if (get_bits1(gb) != 0) {
+             skip_bits(gb, 8); /* constant_alpha_value */
+         }
+     }
+//FIXME complexity estimation stuff
+
+     if (s->shape != BIN_ONLY_SHAPE) {
+         skip_bits_long(gb, s->cplx_estimation_trash_i);
+         if(s->pict_type != FF_I_TYPE)
+            skip_bits_long(gb, s->cplx_estimation_trash_p);
+         if(s->pict_type == FF_B_TYPE)
+            skip_bits_long(gb, s->cplx_estimation_trash_b);
+
+         s->intra_dc_threshold= mpeg4_dc_threshold[ get_bits(gb, 3) ];
+         if(!s->progressive_sequence){
+             s->top_field_first= get_bits1(gb);
+             s->alternate_scan= get_bits1(gb);
+         }else
+             s->alternate_scan= 0;
+     }
+
+     if(s->alternate_scan){
+         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
+         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
+         ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_vertical_scan);
+         ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
+     } else{
+         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
+         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
+         ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_horizontal_scan);
+         ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
+     }
+
+     if(s->pict_type == FF_S_TYPE && (s->vol_sprite_usage==STATIC_SPRITE || s->vol_sprite_usage==GMC_SPRITE)){
+         mpeg4_decode_sprite_trajectory(s, gb);
+         if(s->sprite_brightness_change) av_log(s->avctx, AV_LOG_ERROR, "sprite_brightness_change not supported\n");
+         if(s->vol_sprite_usage==STATIC_SPRITE) av_log(s->avctx, AV_LOG_ERROR, "static sprite not supported\n");
+     }
+
+     if (s->shape != BIN_ONLY_SHAPE) {
+         s->chroma_qscale= s->qscale = get_bits(gb, s->quant_precision);
+         if(s->qscale==0){
+             av_log(s->avctx, AV_LOG_ERROR, "Error, header damaged or not MPEG4 header (qscale=0)\n");
+             return -1; // makes no sense to continue, as there is nothing left from the image then
+         }
+
+         if (s->pict_type != FF_I_TYPE) {
+             s->f_code = get_bits(gb, 3);       /* fcode_for */
+             if(s->f_code==0){
+                 av_log(s->avctx, AV_LOG_ERROR, "Error, header damaged or not MPEG4 header (f_code=0)\n");
+                 return -1; // makes no sense to continue, as the MV decoding will break very quickly
+             }
+         }else
+             s->f_code=1;
+
+         if (s->pict_type == FF_B_TYPE) {
+             s->b_code = get_bits(gb, 3);
+         }else
+             s->b_code=1;
+
+         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
+             av_log(s->avctx, AV_LOG_DEBUG, "qp:%d fc:%d,%d %s size:%d pro:%d alt:%d top:%d %spel part:%d resync:%d w:%d a:%d rnd:%d vot:%d%s dc:%d ce:%d/%d/%d\n",
+                 s->qscale, s->f_code, s->b_code,
+                 s->pict_type == FF_I_TYPE ? "I" : (s->pict_type == FF_P_TYPE ? "P" : (s->pict_type == FF_B_TYPE ? "B" : "S")),
+                 gb->size_in_bits,s->progressive_sequence, s->alternate_scan, s->top_field_first,
+                 s->quarter_sample ? "q" : "h", s->data_partitioning, s->resync_marker, s->num_sprite_warping_points,
+                 s->sprite_warping_accuracy, 1-s->no_rounding, s->vo_type, s->vol_control_parameters ? " VOLC" : " ", s->intra_dc_threshold, s->cplx_estimation_trash_i, s->cplx_estimation_trash_p, s->cplx_estimation_trash_b);
+         }
+
+         if(!s->scalability){
+             if (s->shape!=RECT_SHAPE && s->pict_type!=FF_I_TYPE) {
+                 skip_bits1(gb); // vop shape coding type
+             }
+         }else{
+             if(s->enhancement_type){
+                 int load_backward_shape= get_bits1(gb);
+                 if(load_backward_shape){
+                     av_log(s->avctx, AV_LOG_ERROR, "load backward shape isn't supported\n");
+                 }
+             }
+             skip_bits(gb, 2); //ref_select_code
+         }
+     }
+     /* detect buggy encoders which don't set the low_delay flag (divx4/xvid/opendivx)*/
+     // note we cannot detect divx5 without b-frames easily (although it's buggy too)
+     if(s->vo_type==0 && s->vol_control_parameters==0 && s->divx_version==0 && s->picture_number==0){
+         av_log(s->avctx, AV_LOG_ERROR, "looks like this file was encoded with (divx4/(old)xvid/opendivx) -> forcing low_delay flag\n");
+         s->low_delay=1;
+     }
+
+     s->picture_number++; // better than pic number==0 always ;)
+
+     s->y_dc_scale_table= ff_mpeg4_y_dc_scale_table; //FIXME add short header support
+     s->c_dc_scale_table= ff_mpeg4_c_dc_scale_table;
+
+     if(s->workaround_bugs&FF_BUG_EDGE){
+         s->h_edge_pos= s->width;
+         s->v_edge_pos= s->height;
+     }
+     return 0;
+}
+
+/**
+ * decode mpeg4 headers
+ * @return <0 if no VOP found (or a damaged one)
+ *         FRAME_SKIPPED if a not coded VOP is found
+ *         0 if a VOP is found
+ */
+int ff_mpeg4_decode_picture_header(MpegEncContext * s, GetBitContext *gb)
+{
+    int startcode, v;
+
+    /* search next start code */
+    align_get_bits(gb);
+
+    if(s->codec_tag == AV_RL32("WV1F") && show_bits(gb, 24) == 0x575630){
+        skip_bits(gb, 24);
+        if(get_bits(gb, 8) == 0xF0)
+            goto end;
+    }
+
+    startcode = 0xff;
+    for(;;) {
+        if(get_bits_count(gb) >= gb->size_in_bits){
+            if(gb->size_in_bits==8 && (s->divx_version || s->xvid_build)){
+                av_log(s->avctx, AV_LOG_ERROR, "frame skip %d\n", gb->size_in_bits);
+                return FRAME_SKIPPED; //divx bug
+            }else
+                return -1; //end of stream
+        }
+
+        /* use the bits after the test */
+        v = get_bits(gb, 8);
+        startcode = ((startcode << 8) | v) & 0xffffffff;
+
+        if((startcode&0xFFFFFF00) != 0x100)
+            continue; //no startcode
+
+        if(s->avctx->debug&FF_DEBUG_STARTCODE){
+            av_log(s->avctx, AV_LOG_DEBUG, "startcode: %3X ", startcode);
+            if     (startcode<=0x11F) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Start");
+            else if(startcode<=0x12F) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Layer Start");
+            else if(startcode<=0x13F) av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
+            else if(startcode<=0x15F) av_log(s->avctx, AV_LOG_DEBUG, "FGS bp start");
+            else if(startcode<=0x1AF) av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
+            else if(startcode==0x1B0) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq Start");
+            else if(startcode==0x1B1) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq End");
+            else if(startcode==0x1B2) av_log(s->avctx, AV_LOG_DEBUG, "User Data");
+            else if(startcode==0x1B3) av_log(s->avctx, AV_LOG_DEBUG, "Group of VOP start");
+            else if(startcode==0x1B4) av_log(s->avctx, AV_LOG_DEBUG, "Video Session Error");
+            else if(startcode==0x1B5) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Start");
+            else if(startcode==0x1B6) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Plane start");
+            else if(startcode==0x1B7) av_log(s->avctx, AV_LOG_DEBUG, "slice start");
+            else if(startcode==0x1B8) av_log(s->avctx, AV_LOG_DEBUG, "extension start");
+            else if(startcode==0x1B9) av_log(s->avctx, AV_LOG_DEBUG, "fgs start");
+            else if(startcode==0x1BA) av_log(s->avctx, AV_LOG_DEBUG, "FBA Object start");
+            else if(startcode==0x1BB) av_log(s->avctx, AV_LOG_DEBUG, "FBA Object Plane start");
+            else if(startcode==0x1BC) av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object start");
+            else if(startcode==0x1BD) av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object Plane start");
+            else if(startcode==0x1BE) av_log(s->avctx, AV_LOG_DEBUG, "Still Texture Object start");
+            else if(startcode==0x1BF) av_log(s->avctx, AV_LOG_DEBUG, "Texture Spatial Layer start");
+            else if(startcode==0x1C0) av_log(s->avctx, AV_LOG_DEBUG, "Texture SNR Layer start");
+            else if(startcode==0x1C1) av_log(s->avctx, AV_LOG_DEBUG, "Texture Tile start");
+            else if(startcode==0x1C2) av_log(s->avctx, AV_LOG_DEBUG, "Texture Shape Layer start");
+            else if(startcode==0x1C3) av_log(s->avctx, AV_LOG_DEBUG, "stuffing start");
+            else if(startcode<=0x1C5) av_log(s->avctx, AV_LOG_DEBUG, "reserved");
+            else if(startcode<=0x1FF) av_log(s->avctx, AV_LOG_DEBUG, "System start");
+            av_log(s->avctx, AV_LOG_DEBUG, " at %d\n", get_bits_count(gb));
+        }
+
+        if(startcode >= 0x120 && startcode <= 0x12F){
+            if(decode_vol_header(s, gb) < 0)
+                return -1;
+        }
+        else if(startcode == USER_DATA_STARTCODE){
+            decode_user_data(s, gb);
+        }
+        else if(startcode == GOP_STARTCODE){
+            mpeg4_decode_gop_header(s, gb);
+        }
+        else if(startcode == VOP_STARTCODE){
+            break;
+        }
+
+        align_get_bits(gb);
+        startcode = 0xff;
+    }
+end:
+    if(s->flags& CODEC_FLAG_LOW_DELAY)
+        s->low_delay=1;
+    s->avctx->has_b_frames= !s->low_delay;
+    return decode_vop_header(s, gb);
+}
+
+static av_cold int decode_init(AVCodecContext *avctx)
+{
+    MpegEncContext *s = avctx->priv_data;
+    int ret;
+    static int done = 0;
+
+    if((ret=ff_h263_decode_init(avctx)) < 0)
+        return ret;
+
+    if (!done) {
+        done = 1;
+
+        init_rl(&rl_intra, ff_mpeg4_static_rl_table_store[0]);
+        init_rl(&rvlc_rl_inter, ff_mpeg4_static_rl_table_store[1]);
+        init_rl(&rvlc_rl_intra, ff_mpeg4_static_rl_table_store[2]);
+        INIT_VLC_RL(rl_intra, 554);
+        INIT_VLC_RL(rvlc_rl_inter, 1072);
+        INIT_VLC_RL(rvlc_rl_intra, 1072);
+        INIT_VLC_STATIC(&dc_lum, DC_VLC_BITS, 10 /* 13 */,
+                 &DCtab_lum[0][1], 2, 1,
+                 &DCtab_lum[0][0], 2, 1, 512);
+        INIT_VLC_STATIC(&dc_chrom, DC_VLC_BITS, 10 /* 13 */,
+                 &DCtab_chrom[0][1], 2, 1,
+                 &DCtab_chrom[0][0], 2, 1, 512);
+        INIT_VLC_STATIC(&sprite_trajectory, SPRITE_TRAJ_VLC_BITS, 15,
+                 &sprite_trajectory_tab[0][1], 4, 2,
+                 &sprite_trajectory_tab[0][0], 4, 2, 128);
+        INIT_VLC_STATIC(&mb_type_b_vlc, MB_TYPE_B_VLC_BITS, 4,
+                 &mb_type_b_tab[0][1], 2, 1,
+                 &mb_type_b_tab[0][0], 2, 1, 16);
+    }
+
+    s->h263_pred = 1;
+    s->low_delay = 0; //default, might be overriden in the vol header during header parsing
+    s->decode_mb= mpeg4_decode_mb;
+    s->time_increment_bits = 4; /* default value for broken headers */
+    avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
+
+    return 0;
+}
+
+AVCodec mpeg4_decoder = {
+    "mpeg4",
+    CODEC_TYPE_VIDEO,
+    CODEC_ID_MPEG4,
+    sizeof(MpegEncContext),
+    decode_init,
+    NULL,
+    ff_h263_decode_end,
+    ff_h263_decode_frame,
+    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
+    .flush= ff_mpeg_flush,
+    .long_name= NULL_IF_CONFIG_SMALL("MPEG-4 part 2"),
+    .pix_fmts= ff_hwaccel_pixfmt_list_420,
+};
+
+
+#if CONFIG_MPEG4_VDPAU_DECODER
+AVCodec mpeg4_vdpau_decoder = {
+    "mpeg4_vdpau",
+    CODEC_TYPE_VIDEO,
+    CODEC_ID_MPEG4,
+    sizeof(MpegEncContext),
+    decode_init,
+    NULL,
+    ff_h263_decode_end,
+    ff_h263_decode_frame,
+    CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_HWACCEL_VDPAU,
+    .long_name= NULL_IF_CONFIG_SMALL("MPEG-4 part 2 (VDPAU)"),
+    .pix_fmts= (const enum PixelFormat[]){PIX_FMT_VDPAU_MPEG4, PIX_FMT_NONE},
+};
+#endif

libavcodec/mpeg4videoenc.c

+/*
+ * MPEG4 encoder.
+ * Copyright (c) 2000,2001 Fabrice Bellard
+ * Copyright (c) 2002-2010 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "mpegvideo.h"
+#include "h263.h"
+#include "mpeg4video.h"
+
+//The uni_DCtab_* tables below contain unified bits+length tables to encode DC
+//differences in mpeg4. Unified in the sense that the specification specifies
+//this encoding in several steps.
+static uint8_t uni_DCtab_lum_len[512];
+static uint8_t uni_DCtab_chrom_len[512];
+static uint16_t uni_DCtab_lum_bits[512];
+static uint16_t uni_DCtab_chrom_bits[512];
+
+//unified encoding tables for run length encoding of coefficients
+//unified in the sense that the specification specifies the encoding in several steps.
+static uint32_t uni_mpeg4_intra_rl_bits[64*64*2*2];
+static uint8_t  uni_mpeg4_intra_rl_len [64*64*2*2];
+static uint32_t uni_mpeg4_inter_rl_bits[64*64*2*2];
+static uint8_t  uni_mpeg4_inter_rl_len [64*64*2*2];
+//#define UNI_MPEG4_ENC_INDEX(last,run,level) ((last)*128 + (run)*256 + (level))
+//#define UNI_MPEG4_ENC_INDEX(last,run,level) ((last)*128*64 + (run) + (level)*64)
+#define UNI_MPEG4_ENC_INDEX(last,run,level) ((last)*128*64 + (run)*128 + (level))
+
+/* mpeg4
+inter
+max level: 24/6
+max run: 53/63
+
+intra
+max level: 53/16
+max run: 29/41
+*/
+
+
+/**
+ * Returns the number of bits that encoding the 8x8 block in block would need.
+ * @param[in]  block_last_index last index in scantable order that refers to a non zero element in block.
+ */
+static inline int get_block_rate(MpegEncContext * s, DCTELEM block[64], int block_last_index, uint8_t scantable[64]){
+    int last=0;
+    int j;
+    int rate=0;
+
+    for(j=1; j<=block_last_index; j++){
+        const int index= scantable[j];
+        int level= block[index];
+        if(level){
+            level+= 64;
+            if((level&(~127)) == 0){
+                if(j<block_last_index) rate+= s->intra_ac_vlc_length     [UNI_AC_ENC_INDEX(j-last-1, level)];
+                else                   rate+= s->intra_ac_vlc_last_length[UNI_AC_ENC_INDEX(j-last-1, level)];
+            }else
+                rate += s->ac_esc_length;
+
+            last= j;
+        }
+    }
+
+    return rate;
+}
+
+
+/**
+ * Restores the ac coefficients in block that have been changed by decide_ac_pred().
+ * This function also restores s->block_last_index.
+ * @param[in,out] block MB coefficients, these will be restored
+ * @param[in] dir ac prediction direction for each 8x8 block
+ * @param[out] st scantable for each 8x8 block
+ * @param[in] zigzag_last_index index refering to the last non zero coefficient in zigzag order
+ */
+static inline void restore_ac_coeffs(MpegEncContext * s, DCTELEM block[6][64], const int dir[6], uint8_t *st[6], const int zigzag_last_index[6])
+{
+    int i, n;
+    memcpy(s->block_last_index, zigzag_last_index, sizeof(int)*6);
+
+    for(n=0; n<6; n++){
+        int16_t *ac_val = s->ac_val[0][0] + s->block_index[n] * 16;
+
+        st[n]= s->intra_scantable.permutated;
+        if(dir[n]){
+            /* top prediction */
+            for(i=1; i<8; i++){
+                block[n][s->dsp.idct_permutation[i   ]] = ac_val[i+8];
+            }
+        }else{
+            /* left prediction */
+            for(i=1; i<8; i++){
+                block[n][s->dsp.idct_permutation[i<<3]]= ac_val[i  ];
+            }
+        }
+    }
+}
+
+/**
+ * Returns the optimal value (0 or 1) for the ac_pred element for the given MB in mpeg4.
+ * This function will also update s->block_last_index and s->ac_val.
+ * @param[in,out] block MB coefficients, these will be updated if 1 is returned
+ * @param[in] dir ac prediction direction for each 8x8 block
+ * @param[out] st scantable for each 8x8 block
+ * @param[out] zigzag_last_index index refering to the last non zero coefficient in zigzag order
+ */
+static inline int decide_ac_pred(MpegEncContext * s, DCTELEM block[6][64], const int dir[6], uint8_t *st[6], int zigzag_last_index[6])
+{
+    int score= 0;
+    int i, n;
+    int8_t * const qscale_table= s->current_picture.qscale_table;
+
+    memcpy(zigzag_last_index, s->block_last_index, sizeof(int)*6);
+
+    for(n=0; n<6; n++){
+        int16_t *ac_val, *ac_val1;
+
+        score -= get_block_rate(s, block[n], s->block_last_index[n], s->intra_scantable.permutated);
+
+        ac_val = s->ac_val[0][0] + s->block_index[n] * 16;
+        ac_val1= ac_val;
+        if(dir[n]){
+            const int xy= s->mb_x + s->mb_y*s->mb_stride - s->mb_stride;
+            /* top prediction */
+            ac_val-= s->block_wrap[n]*16;
+            if(s->mb_y==0 || s->qscale == qscale_table[xy] || n==2 || n==3){
+                /* same qscale */
+                for(i=1; i<8; i++){
+                    const int level= block[n][s->dsp.idct_permutation[i   ]];
+                    block[n][s->dsp.idct_permutation[i   ]] = level - ac_val[i+8];
+                    ac_val1[i  ]=    block[n][s->dsp.idct_permutation[i<<3]];
+                    ac_val1[i+8]= level;
+                }
+            }else{
+                /* different qscale, we must rescale */
+                for(i=1; i<8; i++){
+                    const int level= block[n][s->dsp.idct_permutation[i   ]];
+                    block[n][s->dsp.idct_permutation[i   ]] = level - ROUNDED_DIV(ac_val[i + 8]*qscale_table[xy], s->qscale);
+                    ac_val1[i  ]=    block[n][s->dsp.idct_permutation[i<<3]];
+                    ac_val1[i+8]= level;
+                }
+            }
+            st[n]= s->intra_h_scantable.permutated;
+        }else{
+            const int xy= s->mb_x-1 + s->mb_y*s->mb_stride;
+            /* left prediction */
+            ac_val-= 16;
+            if(s->mb_x==0 || s->qscale == qscale_table[xy] || n==1 || n==3){
+                /* same qscale */
+                for(i=1; i<8; i++){
+                    const int level= block[n][s->dsp.idct_permutation[i<<3]];
+                    block[n][s->dsp.idct_permutation[i<<3]]= level - ac_val[i];
+                    ac_val1[i  ]= level;
+                    ac_val1[i+8]=    block[n][s->dsp.idct_permutation[i   ]];
+                }
+            }else{
+                /* different qscale, we must rescale */
+                for(i=1; i<8; i++){
+                    const int level= block[n][s->dsp.idct_permutation[i<<3]];
+                    block[n][s->dsp.idct_permutation[i<<3]]= level - ROUNDED_DIV(ac_val[i]*qscale_table[xy], s->qscale);
+                    ac_val1[i  ]= level;
+                    ac_val1[i+8]=    block[n][s->dsp.idct_permutation[i   ]];
+                }
+            }
+            st[n]= s->intra_v_scantable.permutated;
+        }
+
+        for(i=63; i>0; i--) //FIXME optimize
+            if(block[n][ st[n][i] ]) break;
+        s->block_last_index[n]= i;
+
+        score += get_block_rate(s, block[n], s->block_last_index[n], st[n]);
+    }
+
+    if(score < 0){
+        return 1;
+    }else{
+        restore_ac_coeffs(s, block, dir, st, zigzag_last_index);
+        return 0;
+    }
+}
+
+/**
+ * modify mb_type & qscale so that encoding is acually possible in mpeg4
+ */
+void ff_clean_mpeg4_qscales(MpegEncContext *s){
+    int i;
+    int8_t * const qscale_table= s->current_picture.qscale_table;
+
+    ff_clean_h263_qscales(s);
+
+    if(s->pict_type== FF_B_TYPE){
+        int odd=0;
+        /* ok, come on, this isn't funny anymore, there's more code for handling this mpeg4 mess than for the actual adaptive quantization */
+
+        for(i=0; i<s->mb_num; i++){
+            int mb_xy= s->mb_index2xy[i];
+            odd += qscale_table[mb_xy]&1;
+        }
+
+        if(2*odd > s->mb_num) odd=1;
+        else                  odd=0;
+
+        for(i=0; i<s->mb_num; i++){
+            int mb_xy= s->mb_index2xy[i];
+            if((qscale_table[mb_xy]&1) != odd)
+                qscale_table[mb_xy]++;
+            if(qscale_table[mb_xy] > 31)
+                qscale_table[mb_xy]= 31;
+        }
+
+        for(i=1; i<s->mb_num; i++){
+            int mb_xy= s->mb_index2xy[i];
+            if(qscale_table[mb_xy] != qscale_table[s->mb_index2xy[i-1]] && (s->mb_type[mb_xy]&CANDIDATE_MB_TYPE_DIRECT)){
+                s->mb_type[mb_xy]|= CANDIDATE_MB_TYPE_BIDIR;
+            }
+        }
+    }
+}
+
+
+/**
+ * encodes the dc value.
+ * @param n block index (0-3 are luma, 4-5 are chroma)
+ */
+static inline void mpeg4_encode_dc(PutBitContext * s, int level, int n)
+{
+#if 1
+    level+=256;
+    if (n < 4) {
+        /* luminance */
+        put_bits(s, uni_DCtab_lum_len[level], uni_DCtab_lum_bits[level]);
+    } else {
+        /* chrominance */
+        put_bits(s, uni_DCtab_chrom_len[level], uni_DCtab_chrom_bits[level]);
+    }
+#else
+    int size, v;
+    /* find number of bits */
+    size = 0;
+    v = abs(level);
+    while (v) {
+        v >>= 1;
+        size++;
+    }
+
+    if (n < 4) {
+        /* luminance */
+        put_bits(&s->pb, DCtab_lum[size][1], DCtab_lum[size][0]);
+    } else {
+        /* chrominance */
+        put_bits(&s->pb, DCtab_chrom[size][1], DCtab_chrom[size][0]);
+    }
+
+    /* encode remaining bits */
+    if (size > 0) {
+        if (level < 0)
+            level = (-level) ^ ((1 << size) - 1);
+        put_bits(&s->pb, size, level);
+        if (size > 8)
+            put_bits(&s->pb, 1, 1);
+    }
+#endif
+}
+
+static inline int mpeg4_get_dc_length(int level, int n){
+    if (n < 4) {
+        return uni_DCtab_lum_len[level + 256];
+    } else {
+        return uni_DCtab_chrom_len[level + 256];
+    }
+}
+
+/**
+ * encodes a 8x8 block
+ * @param n block index (0-3 are luma, 4-5 are chroma)
+ */
+static inline void mpeg4_encode_block(MpegEncContext * s, DCTELEM * block, int n, int intra_dc,
+                               uint8_t *scan_table, PutBitContext *dc_pb, PutBitContext *ac_pb)
+{
+    int i, last_non_zero;
+#if 0 //variables for the outcommented version
+    int code, sign, last;
+#endif
+    const RLTable *rl;
+    uint32_t *bits_tab;
+    uint8_t *len_tab;
+    const int last_index = s->block_last_index[n];
+
+    if (s->mb_intra) { //Note gcc (3.2.1 at least) will optimize this away
+        /* mpeg4 based DC predictor */
+        mpeg4_encode_dc(dc_pb, intra_dc, n);
+        if(last_index<1) return;
+        i = 1;
+        rl = &rl_intra;
+        bits_tab= uni_mpeg4_intra_rl_bits;
+        len_tab = uni_mpeg4_intra_rl_len;
+    } else {
+        if(last_index<0) return;
+        i = 0;
+        rl = &rl_inter;
+        bits_tab= uni_mpeg4_inter_rl_bits;
+        len_tab = uni_mpeg4_inter_rl_len;
+    }
+
+    /* AC coefs */
+    last_non_zero = i - 1;
+#if 1
+    for (; i < last_index; i++) {
+        int level = block[ scan_table[i] ];
+        if (level) {
+            int run = i - last_non_zero - 1;
+            level+=64;
+            if((level&(~127)) == 0){
+                const int index= UNI_MPEG4_ENC_INDEX(0, run, level);
+                put_bits(ac_pb, len_tab[index], bits_tab[index]);
+            }else{ //ESC3
+                put_bits(ac_pb, 7+2+1+6+1+12+1, (3<<23)+(3<<21)+(0<<20)+(run<<14)+(1<<13)+(((level-64)&0xfff)<<1)+1);
+            }
+            last_non_zero = i;
+        }
+    }
+    /*if(i<=last_index)*/{
+        int level = block[ scan_table[i] ];
+        int run = i - last_non_zero - 1;
+        level+=64;
+        if((level&(~127)) == 0){
+            const int index= UNI_MPEG4_ENC_INDEX(1, run, level);
+            put_bits(ac_pb, len_tab[index], bits_tab[index]);
+        }else{ //ESC3
+            put_bits(ac_pb, 7+2+1+6+1+12+1, (3<<23)+(3<<21)+(1<<20)+(run<<14)+(1<<13)+(((level-64)&0xfff)<<1)+1);
+        }
+    }
+#else
+    for (; i <= last_index; i++) {
+        const int slevel = block[ scan_table[i] ];
+        if (slevel) {
+            int level;
+            int run = i - last_non_zero - 1;
+            last = (i == last_index);
+            sign = 0;
+            level = slevel;
+            if (level < 0) {
+                sign = 1;
+                level = -level;
+            }
+            code = get_rl_index(rl, last, run, level);
+            put_bits(ac_pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
+            if (code == rl->n) {
+                int level1, run1;
+                level1 = level - rl->max_level[last][run];
+                if (level1 < 1)
+                    goto esc2;
+                code = get_rl_index(rl, last, run, level1);
+                if (code == rl->n) {
+                esc2:
+                    put_bits(ac_pb, 1, 1);
+                    if (level > MAX_LEVEL)
+                        goto esc3;
+                    run1 = run - rl->max_run[last][level] - 1;
+                    if (run1 < 0)
+                        goto esc3;
+                    code = get_rl_index(rl, last, run1, level);
+                    if (code == rl->n) {
+                    esc3:
+                        /* third escape */
+                        put_bits(ac_pb, 1, 1);
+                        put_bits(ac_pb, 1, last);
+                        put_bits(ac_pb, 6, run);
+                        put_bits(ac_pb, 1, 1);
+                        put_sbits(ac_pb, 12, slevel);
+                        put_bits(ac_pb, 1, 1);
+                    } else {
+                        /* second escape */
+                        put_bits(ac_pb, 1, 0);
+                        put_bits(ac_pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
+                        put_bits(ac_pb, 1, sign);
+                    }
+                } else {
+                    /* first escape */
+                    put_bits(ac_pb, 1, 0);
+                    put_bits(ac_pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
+                    put_bits(ac_pb, 1, sign);
+                }
+            } else {
+                put_bits(ac_pb, 1, sign);
+            }
+            last_non_zero = i;
+        }
+    }
+#endif
+}
+
+static int mpeg4_get_block_length(MpegEncContext * s, DCTELEM * block, int n, int intra_dc,
+                               uint8_t *scan_table)
+{
+    int i, last_non_zero;
+    uint8_t *len_tab;
+    const int last_index = s->block_last_index[n];
+    int len=0;
+
+    if (s->mb_intra) { //Note gcc (3.2.1 at least) will optimize this away
+        /* mpeg4 based DC predictor */
+        len += mpeg4_get_dc_length(intra_dc, n);
+        if(last_index<1) return len;
+        i = 1;
+        len_tab = uni_mpeg4_intra_rl_len;
+    } else {
+        if(last_index<0) return 0;
+        i = 0;
+        len_tab = uni_mpeg4_inter_rl_len;
+    }
+
+    /* AC coefs */
+    last_non_zero = i - 1;
+    for (; i < last_index; i++) {
+        int level = block[ scan_table[i] ];
+        if (level) {
+            int run = i - last_non_zero - 1;
+            level+=64;
+            if((level&(~127)) == 0){
+                const int index= UNI_MPEG4_ENC_INDEX(0, run, level);
+                len += len_tab[index];
+            }else{ //ESC3
+                len += 7+2+1+6+1+12+1;
+            }
+            last_non_zero = i;
+        }
+    }
+    /*if(i<=last_index)*/{
+        int level = block[ scan_table[i] ];
+        int run = i - last_non_zero - 1;
+        level+=64;
+        if((level&(~127)) == 0){
+            const int index= UNI_MPEG4_ENC_INDEX(1, run, level);
+            len += len_tab[index];
+        }else{ //ESC3
+            len += 7+2+1+6+1+12+1;
+        }
+    }
+
+    return len;
+}
+
+static inline void mpeg4_encode_blocks(MpegEncContext * s, DCTELEM block[6][64], int intra_dc[6],
+                               uint8_t **scan_table, PutBitContext *dc_pb, PutBitContext *ac_pb){
+    int i;
+
+    if(scan_table){
+        if(s->flags2 & CODEC_FLAG2_NO_OUTPUT){
+            for (i = 0; i < 6; i++) {
+                skip_put_bits(&s->pb, mpeg4_get_block_length(s, block[i], i, intra_dc[i], scan_table[i]));
+            }
+        }else{
+            /* encode each block */
+            for (i = 0; i < 6; i++) {
+                mpeg4_encode_block(s, block[i], i, intra_dc[i], scan_table[i], dc_pb, ac_pb);
+            }
+        }
+    }else{
+        if(s->flags2 & CODEC_FLAG2_NO_OUTPUT){
+            for (i = 0; i < 6; i++) {
+                skip_put_bits(&s->pb, mpeg4_get_block_length(s, block[i], i, 0, s->intra_scantable.permutated));
+            }
+        }else{
+            /* encode each block */
+            for (i = 0; i < 6; i++) {
+                mpeg4_encode_block(s, block[i], i, 0, s->intra_scantable.permutated, dc_pb, ac_pb);
+            }
+        }
+    }
+}
+
+//FIXME this is duplicated to h263.c
+static const int dquant_code[5]= {1,0,9,2,3};
+
+void mpeg4_encode_mb(MpegEncContext * s,
+                    DCTELEM block[6][64],
+                    int motion_x, int motion_y)
+{
+    int cbpc, cbpy, pred_x, pred_y;
+    PutBitContext * const pb2    = s->data_partitioning                         ? &s->pb2    : &s->pb;
+    PutBitContext * const tex_pb = s->data_partitioning && s->pict_type!=FF_B_TYPE ? &s->tex_pb : &s->pb;
+    PutBitContext * const dc_pb  = s->data_partitioning && s->pict_type!=FF_I_TYPE ? &s->pb2    : &s->pb;
+    const int interleaved_stats= (s->flags&CODEC_FLAG_PASS1) && !s->data_partitioning ? 1 : 0;
+
+    if (!s->mb_intra) {
+        int i, cbp;
+
+        if(s->pict_type==FF_B_TYPE){
+            static const int mb_type_table[8]= {-1, 3, 2, 1,-1,-1,-1, 0}; /* convert from mv_dir to type */
+            int mb_type=  mb_type_table[s->mv_dir];
+
+            if(s->mb_x==0){
+                for(i=0; i<2; i++){
+                    s->last_mv[i][0][0]=
+                    s->last_mv[i][0][1]=
+                    s->last_mv[i][1][0]=
+                    s->last_mv[i][1][1]= 0;
+                }
+            }
+
+            assert(s->dquant>=-2 && s->dquant<=2);
+            assert((s->dquant&1)==0);
+            assert(mb_type>=0);
+
+            /* nothing to do if this MB was skipped in the next P Frame */
+            if(s->next_picture.mbskip_table[s->mb_y * s->mb_stride + s->mb_x]){ //FIXME avoid DCT & ...
+                s->skip_count++;
+                s->mv[0][0][0]=
+                s->mv[0][0][1]=
+                s->mv[1][0][0]=
+                s->mv[1][0][1]= 0;
+                s->mv_dir= MV_DIR_FORWARD; //doesn't matter
+                s->qscale -= s->dquant;
+//                s->mb_skipped=1;
+
+                return;
+            }
+
+            cbp= get_b_cbp(s, block, motion_x, motion_y, mb_type);
+
+            if ((cbp | motion_x | motion_y | mb_type) ==0) {
+                /* direct MB with MV={0,0} */
+                assert(s->dquant==0);
+
+                put_bits(&s->pb, 1, 1); /* mb not coded modb1=1 */
+
+                if(interleaved_stats){
+                    s->misc_bits++;
+                    s->last_bits++;
+                }
+                s->skip_count++;
+                return;
+            }
+
+            put_bits(&s->pb, 1, 0);     /* mb coded modb1=0 */
+            put_bits(&s->pb, 1, cbp ? 0 : 1); /* modb2 */ //FIXME merge
+            put_bits(&s->pb, mb_type+1, 1); // this table is so simple that we don't need it :)
+            if(cbp) put_bits(&s->pb, 6, cbp);
+
+            if(cbp && mb_type){
+                if(s->dquant)
+                    put_bits(&s->pb, 2, (s->dquant>>2)+3);
+                else
+                    put_bits(&s->pb, 1, 0);
+            }else
+                s->qscale -= s->dquant;
+
+            if(!s->progressive_sequence){
+                if(cbp)
+                    put_bits(&s->pb, 1, s->interlaced_dct);
+                if(mb_type) // not direct mode
+                    put_bits(&s->pb, 1, s->mv_type == MV_TYPE_FIELD);
+            }
+
+            if(interleaved_stats){
+                s->misc_bits+= get_bits_diff(s);
+            }
+
+            if(mb_type == 0){
+                assert(s->mv_dir & MV_DIRECT);
+                ff_h263_encode_motion_vector(s, motion_x, motion_y, 1);
+                s->b_count++;
+                s->f_count++;
+            }else{
+                assert(mb_type > 0 && mb_type < 4);
+                if(s->mv_type != MV_TYPE_FIELD){
+                    if(s->mv_dir & MV_DIR_FORWARD){
+                        ff_h263_encode_motion_vector(s, s->mv[0][0][0] - s->last_mv[0][0][0],
+                                                        s->mv[0][0][1] - s->last_mv[0][0][1], s->f_code);
+                        s->last_mv[0][0][0]= s->last_mv[0][1][0]= s->mv[0][0][0];
+                        s->last_mv[0][0][1]= s->last_mv[0][1][1]= s->mv[0][0][1];
+                        s->f_count++;
+                    }
+                    if(s->mv_dir & MV_DIR_BACKWARD){
+                        ff_h263_encode_motion_vector(s, s->mv[1][0][0] - s->last_mv[1][0][0],
+                                                        s->mv[1][0][1] - s->last_mv[1][0][1], s->b_code);
+                        s->last_mv[1][0][0]= s->last_mv[1][1][0]= s->mv[1][0][0];
+                        s->last_mv[1][0][1]= s->last_mv[1][1][1]= s->mv[1][0][1];
+                        s->b_count++;
+                    }
+                }else{
+                    if(s->mv_dir & MV_DIR_FORWARD){
+                        put_bits(&s->pb, 1, s->field_select[0][0]);
+                        put_bits(&s->pb, 1, s->field_select[0][1]);
+                    }
+                    if(s->mv_dir & MV_DIR_BACKWARD){
+                        put_bits(&s->pb, 1, s->field_select[1][0]);
+                        put_bits(&s->pb, 1, s->field_select[1][1]);
+                    }
+                    if(s->mv_dir & MV_DIR_FORWARD){
+                        for(i=0; i<2; i++){
+                            ff_h263_encode_motion_vector(s, s->mv[0][i][0] - s->last_mv[0][i][0]  ,
+                                                            s->mv[0][i][1] - s->last_mv[0][i][1]/2, s->f_code);
+                            s->last_mv[0][i][0]= s->mv[0][i][0];
+                            s->last_mv[0][i][1]= s->mv[0][i][1]*2;
+                        }
+                        s->f_count++;
+                    }
+                    if(s->mv_dir & MV_DIR_BACKWARD){
+                        for(i=0; i<2; i++){
+                            ff_h263_encode_motion_vector(s, s->mv[1][i][0] - s->last_mv[1][i][0]  ,
+                                                            s->mv[1][i][1] - s->last_mv[1][i][1]/2, s->b_code);
+                            s->last_mv[1][i][0]= s->mv[1][i][0];
+                            s->last_mv[1][i][1]= s->mv[1][i][1]*2;
+                        }
+                        s->b_count++;
+                    }
+                }
+            }
+
+            if(interleaved_stats){
+                s->mv_bits+= get_bits_diff(s);
+            }
+
+            mpeg4_encode_blocks(s, block, NULL, NULL, NULL, &s->pb);
+
+            if(interleaved_stats){
+                s->p_tex_bits+= get_bits_diff(s);
+            }
+
+        }else{ /* s->pict_type==FF_B_TYPE */
+            cbp= get_p_cbp(s, block, motion_x, motion_y);
+
+            if ((cbp | motion_x | motion_y | s->dquant) == 0 && s->mv_type==MV_TYPE_16X16) {
+                /* check if the B frames can skip it too, as we must skip it if we skip here
+                   why didn't they just compress the skip-mb bits instead of reusing them ?! */
+                if(s->max_b_frames>0){
+                    int i;
+                    int x,y, offset;
+                    uint8_t *p_pic;
+
+                    x= s->mb_x*16;
+                    y= s->mb_y*16;
+                    if(x+16 > s->width)  x= s->width-16;
+                    if(y+16 > s->height) y= s->height-16;
+
+                    offset= x + y*s->linesize;
+                    p_pic= s->new_picture.data[0] + offset;
+
+                    s->mb_skipped=1;
+                    for(i=0; i<s->max_b_frames; i++){
+                        uint8_t *b_pic;
+                        int diff;
+                        Picture *pic= s->reordered_input_picture[i+1];
+
+                        if(pic==NULL || pic->pict_type!=FF_B_TYPE) break;
+
+                        b_pic= pic->data[0] + offset;
+                        if(pic->type != FF_BUFFER_TYPE_SHARED)
+                            b_pic+= INPLACE_OFFSET;
+                        diff= s->dsp.sad[0](NULL, p_pic, b_pic, s->linesize, 16);
+                        if(diff>s->qscale*70){ //FIXME check that 70 is optimal
+                            s->mb_skipped=0;
+                            break;
+                        }
+                    }
+                }else
+                    s->mb_skipped=1;
+
+                if(s->mb_skipped==1){
+                    /* skip macroblock */
+                    put_bits(&s->pb, 1, 1);
+
+                    if(interleaved_stats){
+                        s->misc_bits++;
+                        s->last_bits++;
+                    }
+                    s->skip_count++;
+
+                    return;
+                }
+            }
+
+            put_bits(&s->pb, 1, 0);     /* mb coded */
+            cbpc = cbp & 3;
+            cbpy = cbp >> 2;
+            cbpy ^= 0xf;
+            if(s->mv_type==MV_TYPE_16X16){
+                if(s->dquant) cbpc+= 8;
+                put_bits(&s->pb,
+                        inter_MCBPC_bits[cbpc],
+                        inter_MCBPC_code[cbpc]);
+
+                put_bits(pb2, cbpy_tab[cbpy][1], cbpy_tab[cbpy][0]);
+                if(s->dquant)
+                    put_bits(pb2, 2, dquant_code[s->dquant+2]);
+
+                if(!s->progressive_sequence){
+                    if(cbp)
+                        put_bits(pb2, 1, s->interlaced_dct);
+                    put_bits(pb2, 1, 0);
+                }
+
+                if(interleaved_stats){
+                    s->misc_bits+= get_bits_diff(s);
+                }
+
+                /* motion vectors: 16x16 mode */
+                h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
+
+                ff_h263_encode_motion_vector(s, motion_x - pred_x,
+                                                motion_y - pred_y, s->f_code);
+            }else if(s->mv_type==MV_TYPE_FIELD){
+                if(s->dquant) cbpc+= 8;
+                put_bits(&s->pb,
+                        inter_MCBPC_bits[cbpc],
+                        inter_MCBPC_code[cbpc]);
+
+                put_bits(pb2, cbpy_tab[cbpy][1], cbpy_tab[cbpy][0]);
+                if(s->dquant)
+                    put_bits(pb2, 2, dquant_code[s->dquant+2]);
+
+                assert(!s->progressive_sequence);
+                if(cbp)
+                    put_bits(pb2, 1, s->interlaced_dct);
+                put_bits(pb2, 1, 1);
+
+                if(interleaved_stats){
+                    s->misc_bits+= get_bits_diff(s);
+                }
+
+                /* motion vectors: 16x8 interlaced mode */
+                h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
+                pred_y /=2;
+
+                put_bits(&s->pb, 1, s->field_select[0][0]);
+                put_bits(&s->pb, 1, s->field_select[0][1]);
+
+                ff_h263_encode_motion_vector(s, s->mv[0][0][0] - pred_x,
+                                                s->mv[0][0][1] - pred_y, s->f_code);
+                ff_h263_encode_motion_vector(s, s->mv[0][1][0] - pred_x,
+                                                s->mv[0][1][1] - pred_y, s->f_code);
+            }else{
+                assert(s->mv_type==MV_TYPE_8X8);
+                put_bits(&s->pb,
+                        inter_MCBPC_bits[cbpc+16],
+                        inter_MCBPC_code[cbpc+16]);
+                put_bits(pb2, cbpy_tab[cbpy][1], cbpy_tab[cbpy][0]);
+
+                if(!s->progressive_sequence){
+                    if(cbp)
+                        put_bits(pb2, 1, s->interlaced_dct);
+                }
+
+                if(interleaved_stats){
+                    s->misc_bits+= get_bits_diff(s);
+                }
+
+                for(i=0; i<4; i++){
+                    /* motion vectors: 8x8 mode*/
+                    h263_pred_motion(s, i, 0, &pred_x, &pred_y);
+
+                    ff_h263_encode_motion_vector(s, s->current_picture.motion_val[0][ s->block_index[i] ][0] - pred_x,
+                                                    s->current_picture.motion_val[0][ s->block_index[i] ][1] - pred_y, s->f_code);
+                }
+            }
+
+            if(interleaved_stats){
+                s->mv_bits+= get_bits_diff(s);
+            }
+
+            mpeg4_encode_blocks(s, block, NULL, NULL, NULL, tex_pb);
+
+            if(interleaved_stats){
+                s->p_tex_bits+= get_bits_diff(s);
+            }
+            s->f_count++;
+        }
+    } else {
+        int cbp;
+        int dc_diff[6];   //dc values with the dc prediction subtracted
+        int dir[6];  //prediction direction
+        int zigzag_last_index[6];
+        uint8_t *scan_table[6];
+        int i;
+
+        for(i=0; i<6; i++){
+            dc_diff[i]= ff_mpeg4_pred_dc(s, i, block[i][0], &dir[i], 1);
+        }
+
+        if(s->flags & CODEC_FLAG_AC_PRED){
+            s->ac_pred= decide_ac_pred(s, block, dir, scan_table, zigzag_last_index);
+        }else{
+            for(i=0; i<6; i++)
+                scan_table[i]= s->intra_scantable.permutated;
+        }
+
+        /* compute cbp */
+        cbp = 0;
+        for (i = 0; i < 6; i++) {
+            if (s->block_last_index[i] >= 1)
+                cbp |= 1 << (5 - i);
+        }
+
+        cbpc = cbp & 3;
+        if (s->pict_type == FF_I_TYPE) {
+            if(s->dquant) cbpc+=4;
+            put_bits(&s->pb,
+                intra_MCBPC_bits[cbpc],
+                intra_MCBPC_code[cbpc]);
+        } else {
+            if(s->dquant) cbpc+=8;
+            put_bits(&s->pb, 1, 0);     /* mb coded */
+            put_bits(&s->pb,
+                inter_MCBPC_bits[cbpc + 4],
+                inter_MCBPC_code[cbpc + 4]);
+        }
+        put_bits(pb2, 1, s->ac_pred);
+        cbpy = cbp >> 2;
+        put_bits(pb2, cbpy_tab[cbpy][1], cbpy_tab[cbpy][0]);
+        if(s->dquant)
+            put_bits(dc_pb, 2, dquant_code[s->dquant+2]);
+
+        if(!s->progressive_sequence){
+            put_bits(dc_pb, 1, s->interlaced_dct);
+        }
+
+        if(interleaved_stats){
+            s->misc_bits+= get_bits_diff(s);
+        }
+
+        mpeg4_encode_blocks(s, block, dc_diff, scan_table, dc_pb, tex_pb);
+
+        if(interleaved_stats){
+            s->i_tex_bits+= get_bits_diff(s);
+        }
+        s->i_count++;
+
+        /* restore ac coeffs & last_index stuff if we messed them up with the prediction */
+        if(s->ac_pred)
+            restore_ac_coeffs(s, block, dir, scan_table, zigzag_last_index);
+    }
+}
+
+/**
+ * add mpeg4 stuffing bits (01...1)
+ */
+void ff_mpeg4_stuffing(PutBitContext * pbc)
+{
+    int length;
+    put_bits(pbc, 1, 0);
+    length= (-put_bits_count(pbc))&7;
+    if(length) put_bits(pbc, length, (1<<length)-1);
+}
+
+/* must be called before writing the header */
+void ff_set_mpeg4_time(MpegEncContext * s){
+    if(s->pict_type==FF_B_TYPE){
+        ff_mpeg4_init_direct_mv(s);
+    }else{
+        s->last_time_base= s->time_base;
+        s->time_base= s->time/s->avctx->time_base.den;
+    }
+}
+
+static void mpeg4_encode_gop_header(MpegEncContext * s){
+    int hours, minutes, seconds;
+    int64_t time;
+
+    put_bits(&s->pb, 16, 0);
+    put_bits(&s->pb, 16, GOP_STARTCODE);
+
+    time= s->current_picture_ptr->pts;
+    if(s->reordered_input_picture[1])
+        time= FFMIN(time, s->reordered_input_picture[1]->pts);
+    time= time*s->avctx->time_base.num;
+
+    seconds= time/s->avctx->time_base.den;
+    minutes= seconds/60; seconds %= 60;
+    hours= minutes/60; minutes %= 60;
+    hours%=24;
+
+    put_bits(&s->pb, 5, hours);
+    put_bits(&s->pb, 6, minutes);
+    put_bits(&s->pb, 1, 1);
+    put_bits(&s->pb, 6, seconds);
+
+    put_bits(&s->pb, 1, !!(s->flags&CODEC_FLAG_CLOSED_GOP));
+    put_bits(&s->pb, 1, 0); //broken link == NO
+
+    s->last_time_base= time / s->avctx->time_base.den;
+
+    ff_mpeg4_stuffing(&s->pb);
+}
+
+static void mpeg4_encode_visual_object_header(MpegEncContext * s){
+    int profile_and_level_indication;
+    int vo_ver_id;
+
+    if(s->avctx->profile != FF_PROFILE_UNKNOWN){
+        profile_and_level_indication = s->avctx->profile << 4;
+    }else if(s->max_b_frames || s->quarter_sample){
+        profile_and_level_indication= 0xF0; // adv simple
+    }else{
+        profile_and_level_indication= 0x00; // simple
+    }
+
+    if(s->avctx->level != FF_LEVEL_UNKNOWN){
+        profile_and_level_indication |= s->avctx->level;
+    }else{
+        profile_and_level_indication |= 1; //level 1
+    }
+
+    if(profile_and_level_indication>>4 == 0xF){
+        vo_ver_id= 5;
+    }else{
+        vo_ver_id= 1;
+    }
+
+    //FIXME levels
+
+    put_bits(&s->pb, 16, 0);
+    put_bits(&s->pb, 16, VOS_STARTCODE);
+
+    put_bits(&s->pb, 8, profile_and_level_indication);
+
+    put_bits(&s->pb, 16, 0);
+    put_bits(&s->pb, 16, VISUAL_OBJ_STARTCODE);
+
+    put_bits(&s->pb, 1, 1);
+        put_bits(&s->pb, 4, vo_ver_id);
+        put_bits(&s->pb, 3, 1); //priority
+
+    put_bits(&s->pb, 4, 1); //visual obj type== video obj
+
+    put_bits(&s->pb, 1, 0); //video signal type == no clue //FIXME
+
+    ff_mpeg4_stuffing(&s->pb);
+}
+
+static void mpeg4_encode_vol_header(MpegEncContext * s, int vo_number, int vol_number)
+{
+    int vo_ver_id;
+
+    if (!CONFIG_MPEG4_ENCODER)  return;
+
+    if(s->max_b_frames || s->quarter_sample){
+        vo_ver_id= 5;
+        s->vo_type= ADV_SIMPLE_VO_TYPE;
+    }else{
+        vo_ver_id= 1;
+        s->vo_type= SIMPLE_VO_TYPE;
+    }
+
+    put_bits(&s->pb, 16, 0);
+    put_bits(&s->pb, 16, 0x100 + vo_number);        /* video obj */
+    put_bits(&s->pb, 16, 0);
+    put_bits(&s->pb, 16, 0x120 + vol_number);       /* video obj layer */
+
+    put_bits(&s->pb, 1, 0);             /* random access vol */
+    put_bits(&s->pb, 8, s->vo_type);    /* video obj type indication */
+    if(s->workaround_bugs & FF_BUG_MS) {
+        put_bits(&s->pb, 1, 0);         /* is obj layer id= no */
+    } else {
+        put_bits(&s->pb, 1, 1);         /* is obj layer id= yes */
+        put_bits(&s->pb, 4, vo_ver_id); /* is obj layer ver id */
+        put_bits(&s->pb, 3, 1);         /* is obj layer priority */
+    }
+
+    s->aspect_ratio_info= ff_h263_aspect_to_info(s->avctx->sample_aspect_ratio);
+
+    put_bits(&s->pb, 4, s->aspect_ratio_info);/* aspect ratio info */
+    if (s->aspect_ratio_info == FF_ASPECT_EXTENDED){
+        put_bits(&s->pb, 8, s->avctx->sample_aspect_ratio.num);
+        put_bits(&s->pb, 8, s->avctx->sample_aspect_ratio.den);
+    }
+
+    if(s->workaround_bugs & FF_BUG_MS) { //
+        put_bits(&s->pb, 1, 0);         /* vol control parameters= no @@@ */
+    } else {
+        put_bits(&s->pb, 1, 1);         /* vol control parameters= yes */
+        put_bits(&s->pb, 2, 1);         /* chroma format YUV 420/YV12 */
+        put_bits(&s->pb, 1, s->low_delay);
+        put_bits(&s->pb, 1, 0);         /* vbv parameters= no */
+    }
+
+    put_bits(&s->pb, 2, RECT_SHAPE);    /* vol shape= rectangle */
+    put_bits(&s->pb, 1, 1);             /* marker bit */
+
+    put_bits(&s->pb, 16, s->avctx->time_base.den);
+    if (s->time_increment_bits < 1)
+        s->time_increment_bits = 1;
+    put_bits(&s->pb, 1, 1);             /* marker bit */
+    put_bits(&s->pb, 1, 0);             /* fixed vop rate=no */
+    put_bits(&s->pb, 1, 1);             /* marker bit */
+    put_bits(&s->pb, 13, s->width);     /* vol width */
+    put_bits(&s->pb, 1, 1);             /* marker bit */
+    put_bits(&s->pb, 13, s->height);    /* vol height */
+    put_bits(&s->pb, 1, 1);             /* marker bit */
+    put_bits(&s->pb, 1, s->progressive_sequence ? 0 : 1);
+    put_bits(&s->pb, 1, 1);             /* obmc disable */
+    if (vo_ver_id == 1) {
+        put_bits(&s->pb, 1, s->vol_sprite_usage);       /* sprite enable */
+    }else{
+        put_bits(&s->pb, 2, s->vol_sprite_usage);       /* sprite enable */
+    }
+
+    put_bits(&s->pb, 1, 0);             /* not 8 bit == false */
+    put_bits(&s->pb, 1, s->mpeg_quant); /* quant type= (0=h263 style)*/
+
+    if(s->mpeg_quant){
+        ff_write_quant_matrix(&s->pb, s->avctx->intra_matrix);
+        ff_write_quant_matrix(&s->pb, s->avctx->inter_matrix);
+    }
+
+    if (vo_ver_id != 1)
+        put_bits(&s->pb, 1, s->quarter_sample);
+    put_bits(&s->pb, 1, 1);             /* complexity estimation disable */
+    s->resync_marker= s->rtp_mode;
+    put_bits(&s->pb, 1, s->resync_marker ? 0 : 1);/* resync marker disable */
+    put_bits(&s->pb, 1, s->data_partitioning ? 1 : 0);
+    if(s->data_partitioning){
+        put_bits(&s->pb, 1, 0);         /* no rvlc */
+    }
+
+    if (vo_ver_id != 1){
+        put_bits(&s->pb, 1, 0);         /* newpred */
+        put_bits(&s->pb, 1, 0);         /* reduced res vop */
+    }
+    put_bits(&s->pb, 1, 0);             /* scalability */
+
+    ff_mpeg4_stuffing(&s->pb);
+
+    /* user data */
+    if(!(s->flags & CODEC_FLAG_BITEXACT)){
+        put_bits(&s->pb, 16, 0);
+        put_bits(&s->pb, 16, 0x1B2);    /* user_data */
+        ff_put_string(&s->pb, LIBAVCODEC_IDENT, 0);
+    }
+}
+
+/* write mpeg4 VOP header */
+void mpeg4_encode_picture_header(MpegEncContext * s, int picture_number)
+{
+    int time_incr;
+    int time_div, time_mod;
+
+    if(s->pict_type==FF_I_TYPE){
+        if(!(s->flags&CODEC_FLAG_GLOBAL_HEADER)){
+            if(s->strict_std_compliance < FF_COMPLIANCE_VERY_STRICT) //HACK, the reference sw is buggy
+                mpeg4_encode_visual_object_header(s);
+            if(s->strict_std_compliance < FF_COMPLIANCE_VERY_STRICT || picture_number==0) //HACK, the reference sw is buggy
+                mpeg4_encode_vol_header(s, 0, 0);
+        }
+        if(!(s->workaround_bugs & FF_BUG_MS))
+            mpeg4_encode_gop_header(s);
+    }
+
+    s->partitioned_frame= s->data_partitioning && s->pict_type!=FF_B_TYPE;
+
+    put_bits(&s->pb, 16, 0);                /* vop header */
+    put_bits(&s->pb, 16, VOP_STARTCODE);    /* vop header */
+    put_bits(&s->pb, 2, s->pict_type - 1);  /* pict type: I = 0 , P = 1 */
+
+    assert(s->time>=0);
+    time_div= s->time/s->avctx->time_base.den;
+    time_mod= s->time%s->avctx->time_base.den;
+    time_incr= time_div - s->last_time_base;
+    assert(time_incr >= 0);
+    while(time_incr--)
+        put_bits(&s->pb, 1, 1);
+
+    put_bits(&s->pb, 1, 0);
+
+    put_bits(&s->pb, 1, 1);                             /* marker */
+    put_bits(&s->pb, s->time_increment_bits, time_mod); /* time increment */
+    put_bits(&s->pb, 1, 1);                             /* marker */
+    put_bits(&s->pb, 1, 1);                             /* vop coded */
+    if (    s->pict_type == FF_P_TYPE
+        || (s->pict_type == FF_S_TYPE && s->vol_sprite_usage==GMC_SPRITE)) {
+        put_bits(&s->pb, 1, s->no_rounding);    /* rounding type */
+    }
+    put_bits(&s->pb, 3, 0);     /* intra dc VLC threshold */
+    if(!s->progressive_sequence){
+         put_bits(&s->pb, 1, s->current_picture_ptr->top_field_first);
+         put_bits(&s->pb, 1, s->alternate_scan);
+    }
+    //FIXME sprite stuff
+
+    put_bits(&s->pb, 5, s->qscale);
+
+    if (s->pict_type != FF_I_TYPE)
+        put_bits(&s->pb, 3, s->f_code); /* fcode_for */
+    if (s->pict_type == FF_B_TYPE)
+        put_bits(&s->pb, 3, s->b_code); /* fcode_back */
+}
+
+
+static void init_uni_dc_tab(void)
+{
+    int level, uni_code, uni_len;
+
+    for(level=-256; level<256; level++){
+        int size, v, l;
+        /* find number of bits */
+        size = 0;
+        v = abs(level);
+        while (v) {
+            v >>= 1;
+            size++;
+        }
+
+        if (level < 0)
+            l= (-level) ^ ((1 << size) - 1);
+        else
+            l= level;
+
+        /* luminance */
+        uni_code= DCtab_lum[size][0];
+        uni_len = DCtab_lum[size][1];
+
+        if (size > 0) {
+            uni_code<<=size; uni_code|=l;
+            uni_len+=size;
+            if (size > 8){
+                uni_code<<=1; uni_code|=1;
+                uni_len++;
+            }
+        }
+        uni_DCtab_lum_bits[level+256]= uni_code;
+        uni_DCtab_lum_len [level+256]= uni_len;
+
+        /* chrominance */
+        uni_code= DCtab_chrom[size][0];
+        uni_len = DCtab_chrom[size][1];
+
+        if (size > 0) {
+            uni_code<<=size; uni_code|=l;
+            uni_len+=size;
+            if (size > 8){
+                uni_code<<=1; uni_code|=1;
+                uni_len++;
+            }
+        }
+        uni_DCtab_chrom_bits[level+256]= uni_code;
+        uni_DCtab_chrom_len [level+256]= uni_len;
+
+    }
+}
+
+static void init_uni_mpeg4_rl_tab(RLTable *rl, uint32_t *bits_tab, uint8_t *len_tab){
+    int slevel, run, last;
+
+    assert(MAX_LEVEL >= 64);
+    assert(MAX_RUN   >= 63);
+
+    for(slevel=-64; slevel<64; slevel++){
+        if(slevel==0) continue;
+        for(run=0; run<64; run++){
+            for(last=0; last<=1; last++){
+                const int index= UNI_MPEG4_ENC_INDEX(last, run, slevel+64);
+                int level= slevel < 0 ? -slevel : slevel;
+                int sign= slevel < 0 ? 1 : 0;
+                int bits, len, code;
+                int level1, run1;
+
+                len_tab[index]= 100;
+
+                /* ESC0 */
+                code= get_rl_index(rl, last, run, level);
+                bits= rl->table_vlc[code][0];
+                len=  rl->table_vlc[code][1];
+                bits=bits*2+sign; len++;
+
+                if(code!=rl->n && len < len_tab[index]){
+                    bits_tab[index]= bits;
+                    len_tab [index]= len;
+                }
+                /* ESC1 */
+                bits= rl->table_vlc[rl->n][0];
+                len=  rl->table_vlc[rl->n][1];
+                bits=bits*2;    len++; //esc1
+                level1= level - rl->max_level[last][run];
+                if(level1>0){
+                    code= get_rl_index(rl, last, run, level1);
+                    bits<<= rl->table_vlc[code][1];
+                    len  += rl->table_vlc[code][1];
+                    bits += rl->table_vlc[code][0];
+                    bits=bits*2+sign; len++;
+
+                    if(code!=rl->n && len < len_tab[index]){
+                        bits_tab[index]= bits;
+                        len_tab [index]= len;
+                    }
+                }
+                /* ESC2 */
+                bits= rl->table_vlc[rl->n][0];
+                len=  rl->table_vlc[rl->n][1];
+                bits=bits*4+2;    len+=2; //esc2
+                run1 = run - rl->max_run[last][level] - 1;
+                if(run1>=0){
+                    code= get_rl_index(rl, last, run1, level);
+                    bits<<= rl->table_vlc[code][1];
+                    len  += rl->table_vlc[code][1];
+                    bits += rl->table_vlc[code][0];
+                    bits=bits*2+sign; len++;
+
+                    if(code!=rl->n && len < len_tab[index]){
+                        bits_tab[index]= bits;
+                        len_tab [index]= len;
+                    }
+                }
+                /* ESC3 */
+                bits= rl->table_vlc[rl->n][0];
+                len = rl->table_vlc[rl->n][1];
+                bits=bits*4+3;    len+=2; //esc3
+                bits=bits*2+last; len++;
+                bits=bits*64+run; len+=6;
+                bits=bits*2+1;    len++;  //marker
+                bits=bits*4096+(slevel&0xfff); len+=12;
+                bits=bits*2+1;    len++;  //marker
+
+                if(len < len_tab[index]){
+                    bits_tab[index]= bits;
+                    len_tab [index]= len;
+                }
+            }
+        }
+    }
+}
+
+static av_cold int encode_init(AVCodecContext *avctx)
+{
+    MpegEncContext *s = avctx->priv_data;
+    int ret;
+    static int done = 0;
+
+    if((ret=MPV_encode_init(avctx)) < 0)
+        return ret;
+
+    if (!done) {
+        done = 1;
+
+        init_uni_dc_tab();
+
+        init_rl(&rl_intra, ff_mpeg4_static_rl_table_store[0]);
+
+        init_uni_mpeg4_rl_tab(&rl_intra, uni_mpeg4_intra_rl_bits, uni_mpeg4_intra_rl_len);
+        init_uni_mpeg4_rl_tab(&rl_inter, uni_mpeg4_inter_rl_bits, uni_mpeg4_inter_rl_len);
+    }
+
+    s->min_qcoeff= -2048;
+    s->max_qcoeff=  2047;
+    s->intra_ac_vlc_length     = uni_mpeg4_intra_rl_len;
+    s->intra_ac_vlc_last_length= uni_mpeg4_intra_rl_len + 128*64;
+    s->inter_ac_vlc_length     = uni_mpeg4_inter_rl_len;
+    s->inter_ac_vlc_last_length= uni_mpeg4_inter_rl_len + 128*64;
+    s->luma_dc_vlc_length= uni_DCtab_lum_len;
+    s->chroma_dc_vlc_length= uni_DCtab_chrom_len;
+    s->ac_esc_length= 7+2+1+6+1+12+1;
+    s->y_dc_scale_table= ff_mpeg4_y_dc_scale_table;
+    s->c_dc_scale_table= ff_mpeg4_c_dc_scale_table;
+
+    if(s->flags & CODEC_FLAG_GLOBAL_HEADER){
+
+        s->avctx->extradata= av_malloc(1024);
+        init_put_bits(&s->pb, s->avctx->extradata, 1024);
+
+        if(!(s->workaround_bugs & FF_BUG_MS))
+            mpeg4_encode_visual_object_header(s);
+        mpeg4_encode_vol_header(s, 0, 0);
+
+//            ff_mpeg4_stuffing(&s->pb); ?
+        flush_put_bits(&s->pb);
+        s->avctx->extradata_size= (put_bits_count(&s->pb)+7)>>3;
+    }
+    return 0;
+}
+
+void ff_mpeg4_init_partitions(MpegEncContext *s)
+{
+    uint8_t *start= put_bits_ptr(&s->pb);
+    uint8_t *end= s->pb.buf_end;
+    int size= end - start;
+    int pb_size = (((intptr_t)start + size/3)&(~3)) - (intptr_t)start;
+    int tex_size= (size - 2*pb_size)&(~3);
+
+    set_put_bits_buffer_size(&s->pb, pb_size);
+    init_put_bits(&s->tex_pb, start + pb_size           , tex_size);
+    init_put_bits(&s->pb2   , start + pb_size + tex_size, pb_size);
+}
+
+void ff_mpeg4_merge_partitions(MpegEncContext *s)
+{
+    const int pb2_len   = put_bits_count(&s->pb2   );
+    const int tex_pb_len= put_bits_count(&s->tex_pb);
+    const int bits= put_bits_count(&s->pb);
+
+    if(s->pict_type==FF_I_TYPE){
+        put_bits(&s->pb, 19, DC_MARKER);
+        s->misc_bits+=19 + pb2_len + bits - s->last_bits;
+        s->i_tex_bits+= tex_pb_len;
+    }else{
+        put_bits(&s->pb, 17, MOTION_MARKER);
+        s->misc_bits+=17 + pb2_len;
+        s->mv_bits+= bits - s->last_bits;
+        s->p_tex_bits+= tex_pb_len;
+    }
+
+    flush_put_bits(&s->pb2);
+    flush_put_bits(&s->tex_pb);
+
+    set_put_bits_buffer_size(&s->pb, s->pb2.buf_end - s->pb.buf);
+    ff_copy_bits(&s->pb, s->pb2.buf   , pb2_len);
+    ff_copy_bits(&s->pb, s->tex_pb.buf, tex_pb_len);
+    s->last_bits= put_bits_count(&s->pb);
+}
+
+
+void ff_mpeg4_encode_video_packet_header(MpegEncContext *s)
+{
+    int mb_num_bits= av_log2(s->mb_num - 1) + 1;
+
+    put_bits(&s->pb, ff_mpeg4_get_video_packet_prefix_length(s), 0);
+    put_bits(&s->pb, 1, 1);
+
+    put_bits(&s->pb, mb_num_bits, s->mb_x + s->mb_y*s->mb_width);
+    put_bits(&s->pb, s->quant_precision, s->qscale);
+    put_bits(&s->pb, 1, 0); /* no HEC */
+}
+
+AVCodec mpeg4_encoder = {
+    "mpeg4",
+    CODEC_TYPE_VIDEO,
+    CODEC_ID_MPEG4,
+    sizeof(MpegEncContext),
+    encode_init,
+    MPV_encode_picture,
+    MPV_encode_end,
+    .pix_fmts= (const enum PixelFormat[]){PIX_FMT_YUV420P, PIX_FMT_NONE},
+    .capabilities= CODEC_CAP_DELAY,
+    .long_name= NULL_IF_CONFIG_SMALL("MPEG-4 part 2"),
+};

libavcodec/mpegvideo.h

@@ -782,11 +782,7 @@ void ff_mpeg1_encode_slice_header(MpegEncContext *s);
 void ff_mpeg1_clean_buffers(MpegEncContext *s);
 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, AVCodecParserContext *s);
 
-extern const uint8_t ff_mpeg4_y_dc_scale_table[32];
-extern const uint8_t ff_mpeg4_c_dc_scale_table[32];
 extern const uint8_t ff_aic_dc_scale_table[32];
-extern const int16_t ff_mpeg4_default_intra_matrix[64];
-extern const int16_t ff_mpeg4_default_non_intra_matrix[64];
 extern const uint8_t ff_h263_chroma_qscale_table[32];
 extern const uint8_t ff_h263_loop_filter_strength[32];
 
@@ -810,22 +806,14 @@ int ff_h263_decode_end(AVCodecContext *avctx);
 void h263_encode_mb(MpegEncContext *s,
                     DCTELEM block[6][64],
                     int motion_x, int motion_y);
-void mpeg4_encode_mb(MpegEncContext *s,
-                    DCTELEM block[6][64],
-                    int motion_x, int motion_y);
 void h263_encode_picture_header(MpegEncContext *s, int picture_number);
 void h263_encode_gob_header(MpegEncContext * s, int mb_line);
 int16_t *h263_pred_motion(MpegEncContext * s, int block, int dir,
                         int *px, int *py);
-void mpeg4_pred_ac(MpegEncContext * s, DCTELEM *block, int n,
-                   int dir);
-void ff_set_mpeg4_time(MpegEncContext * s);
-void mpeg4_encode_picture_header(MpegEncContext *s, int picture_number);
 void h263_encode_init(MpegEncContext *s);
 void h263_decode_init_vlc(MpegEncContext *s);
 int h263_decode_picture_header(MpegEncContext *s);
 int ff_h263_decode_gob_header(MpegEncContext *s);
-int ff_mpeg4_decode_picture_header(MpegEncContext * s, GetBitContext *gb);
 void ff_h263_update_motion_val(MpegEncContext * s);
 void ff_h263_loop_filter(MpegEncContext * s);
 void ff_set_qscale(MpegEncContext * s, int qscale);
@@ -840,8 +828,6 @@ void ff_h263_show_pict_info(MpegEncContext *s);
 int ff_intel_h263_decode_picture_header(MpegEncContext *s);
 int ff_h263_decode_mb(MpegEncContext *s,
                       DCTELEM block[6][64]);
-int ff_mpeg4_decode_mb(MpegEncContext *s,
-                      DCTELEM block[6][64]);
 
 /**
  * Returns the value of the 3bit "source format" syntax element.
@@ -850,15 +836,7 @@ int ff_mpeg4_decode_mb(MpegEncContext *s,
  */
 int av_const h263_get_picture_format(int width, int height);
 
-void ff_mpeg4_encode_video_packet_header(MpegEncContext *s);
-void ff_mpeg4_clean_buffers(MpegEncContext *s);
-void ff_mpeg4_stuffing(PutBitContext * pbc);
-void ff_mpeg4_init_partitions(MpegEncContext *s);
-void ff_mpeg4_merge_partitions(MpegEncContext *s);
-void ff_clean_mpeg4_qscales(MpegEncContext *s);
 void ff_clean_h263_qscales(MpegEncContext *s);
-int ff_mpeg4_decode_partitions(MpegEncContext *s);
-int ff_mpeg4_get_video_packet_prefix_length(MpegEncContext *s);
 int ff_h263_resync(MpegEncContext *s);
 const uint8_t *ff_h263_find_resync_marker(const uint8_t *p, const uint8_t *end);
 int ff_h263_get_gob_height(MpegEncContext *s);

libavcodec/mpegvideo_enc.c

@@ -36,6 +36,7 @@
 #include "faandct.h"
 #include "aandcttab.h"
 #include "flv.h"
+#include "mpeg4video.h"
 #include <limits.h>
 
 //#undef NDEBUG
@@ -3781,19 +3782,6 @@ AVCodec h263p_encoder = {
     .long_name= NULL_IF_CONFIG_SMALL("H.263+ / H.263-1998 / H.263 version 2"),
 };
 
-AVCodec mpeg4_encoder = {
-    "mpeg4",
-    CODEC_TYPE_VIDEO,
-    CODEC_ID_MPEG4,
-    sizeof(MpegEncContext),
-    MPV_encode_init,
-    MPV_encode_picture,
-    MPV_encode_end,
-    .pix_fmts= (const enum PixelFormat[]){PIX_FMT_YUV420P, PIX_FMT_NONE},
-    .capabilities= CODEC_CAP_DELAY,
-    .long_name= NULL_IF_CONFIG_SMALL("MPEG-4 part 2"),
-};
-
 AVCodec msmpeg4v1_encoder = {
     "msmpeg4v1",
     CODEC_TYPE_VIDEO,

libavcodec/msmpeg4.c

@@ -32,6 +32,8 @@
 #include "mpegvideo.h"
 #include "msmpeg4.h"
 #include "libavutil/x86_cpu.h"
+#include "h263.h"
+#include "mpeg4video.h"
 
 /*
  * You can also call this codec : MPEG4 with a twist !
@@ -43,7 +45,6 @@
 //#define DEBUG
 
 #define DC_VLC_BITS 9
-#define CBPY_VLC_BITS 6
 #define V1_INTRA_CBPC_VLC_BITS 6
 #define V1_INTER_CBPC_VLC_BITS 6
 #define V2_INTRA_CBPC_VLC_BITS 3
@@ -1059,7 +1060,6 @@ else
 VLC ff_mb_non_intra_vlc[4];
 static VLC v2_dc_lum_vlc;
 static VLC v2_dc_chroma_vlc;
-static VLC cbpy_vlc;
 static VLC v2_intra_cbpc_vlc;
 static VLC v2_mb_type_vlc;
 static VLC v2_mv_vlc;

libavcodec/msmpeg4data.h

@@ -52,19 +52,6 @@ extern VLC ff_msmp4_dc_chroma_vlc[2];
 /* intra picture macroblock coded block pattern */
 extern const uint16_t ff_msmp4_mb_i_table[64][2];
 
-extern const uint8_t cbpy_tab[16][2];
-
-extern const uint8_t DCtab_lum[13][2];
-extern const uint8_t DCtab_chrom[13][2];
-
-extern const uint8_t mvtab[33][2];
-
-extern const uint8_t intra_MCBPC_code[9];
-extern const uint8_t intra_MCBPC_bits[9];
-
-extern const uint8_t inter_MCBPC_code[28];
-extern const uint8_t inter_MCBPC_bits[28];
-
 #define WMV1_SCANTABLE_COUNT 4
 
 extern const uint8_t wmv1_scantable[WMV1_SCANTABLE_COUNT][64];