MSS2 decoder

Signed-off-by: Kostya Shishkov <kostya.shishkov@gmail.com>

Changelog

@@ -45,6 +45,7 @@ version <next>:
 - avconv -shortest option is now per-output file,
   -pass and -passlogfile are now per-output stream
 - Ut Video encoder
+- Microsoft Screen 2 decoder
 
 
 version 0.8:

configure

@@ -1479,6 +1479,7 @@ msmpeg4v2_decoder_select="h263_decoder"
 msmpeg4v2_encoder_select="h263_encoder"
 msmpeg4v3_decoder_select="h263_decoder"
 msmpeg4v3_encoder_select="h263_encoder"
+mss2_decoder_select="vc1_decoder"
 nellymoser_decoder_select="mdct sinewin"
 nellymoser_encoder_select="mdct sinewin"
 png_decoder_select="zlib"

doc/general.texi

@@ -547,6 +547,8 @@ following image formats are supported:
 @item Microsoft RLE          @tab     @tab  X
 @item Microsoft Screen 1     @tab     @tab  X
     @tab Also known as Windows Media Video V7 Screen.
+@item Microsoft Screen 2     @tab     @tab  X
+    @tab Also known as Windows Media Video V9 Screen.
 @item Microsoft Video 1      @tab     @tab  X
 @item Mimic                  @tab     @tab  X
     @tab Used in MSN Messenger Webcam streams.

libavcodec/Makefile

@@ -271,6 +271,7 @@ OBJS-$(CONFIG_MSMPEG4V3_ENCODER)       += msmpeg4.o msmpeg4enc.o msmpeg4data.o \
 OBJS-$(CONFIG_MSRLE_DECODER)           += msrle.o msrledec.o
 OBJS-$(CONFIG_MSA1_DECODER)            += mss3.o mss34dsp.o
 OBJS-$(CONFIG_MSS1_DECODER)            += mss1.o mss12.o
+OBJS-$(CONFIG_MSS2_DECODER)            += mss2.o mss12.o mss2dsp.o
 OBJS-$(CONFIG_MSVIDEO1_DECODER)        += msvideo1.o
 OBJS-$(CONFIG_MSZH_DECODER)            += lcldec.o
 OBJS-$(CONFIG_MTS2_DECODER)            += mss4.o mss34dsp.o

libavcodec/allcodecs.c

@@ -160,6 +160,7 @@ void avcodec_register_all(void)
     REGISTER_ENCDEC  (MSMPEG4V3, msmpeg4v3);
     REGISTER_DECODER (MSRLE, msrle);
     REGISTER_DECODER (MSS1, mss1);
+    REGISTER_DECODER (MSS2, mss2);
     REGISTER_DECODER (MSVIDEO1, msvideo1);
     REGISTER_DECODER (MSZH, mszh);
     REGISTER_DECODER (MTS2, mts2);

libavcodec/avcodec.h

@@ -264,6 +264,7 @@ enum AVCodecID {
     AV_CODEC_ID_TSCC2,
     AV_CODEC_ID_MTS2,
     AV_CODEC_ID_CLLC,
+    AV_CODEC_ID_MSS2,
 
     /* various PCM "codecs" */
     AV_CODEC_ID_FIRST_AUDIO = 0x10000,     ///< A dummy id pointing at the start of audio codecs

libavcodec/codec_desc.c

@@ -1200,6 +1200,13 @@ static const AVCodecDescriptor codec_descriptors[] = {
         .long_name = NULL_IF_CONFIG_SMALL("Canopus Lossless Codec"),
         .props     = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSLESS,
     },
+    {
+        .id        = AV_CODEC_ID_MSS2,
+        .type      = AVMEDIA_TYPE_VIDEO,
+        .name      = "mss2",
+        .long_name = NULL_IF_CONFIG_SMALL("MS Windows Media Video V9 Screen"),
+        .props     = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSY,
+    },
 
     /* various PCM "codecs" */
     {

libavcodec/h263dec.c

@@ -58,7 +58,10 @@ av_cold int ff_h263_decode_init(AVCodecContext *avctx)
     s->quant_precision=5;
     s->decode_mb= ff_h263_decode_mb;
     s->low_delay= 1;
-    avctx->pix_fmt= avctx->get_format(avctx, avctx->codec->pix_fmts);
+    if (avctx->codec->id == AV_CODEC_ID_MSS2)
+        avctx->pix_fmt = PIX_FMT_YUV420P;
+    else
+        avctx->pix_fmt = avctx->get_format(avctx, avctx->codec->pix_fmts);
     s->unrestricted_mv= 1;
 
     /* select sub codec */
@@ -93,6 +96,7 @@ av_cold int ff_h263_decode_init(AVCodecContext *avctx)
     case AV_CODEC_ID_WMV3:
     case AV_CODEC_ID_VC1IMAGE:
     case AV_CODEC_ID_WMV3IMAGE:
+    case AV_CODEC_ID_MSS2:
         s->h263_pred = 1;
         s->msmpeg4_version=6;
         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;

libavcodec/mpegvideo.c

@@ -226,10 +226,11 @@ void ff_copy_picture(Picture *dst, Picture *src)
  */
 static void free_frame_buffer(MpegEncContext *s, Picture *pic)
 {
-    /* Windows Media Image codecs allocate internal buffers with different
-     * dimensions; ignore user defined callbacks for these
-     */
-    if (s->codec_id != AV_CODEC_ID_WMV3IMAGE && s->codec_id != AV_CODEC_ID_VC1IMAGE)
+    /* WM Image / Screen codecs allocate internal buffers with different
+     * dimensions / colorspaces; ignore user-defined callbacks for these. */
+    if (s->codec_id != AV_CODEC_ID_WMV3IMAGE &&
+        s->codec_id != AV_CODEC_ID_VC1IMAGE  &&
+        s->codec_id != AV_CODEC_ID_MSS2)
         ff_thread_release_buffer(s->avctx, &pic->f);
     else
         avcodec_default_release_buffer(s->avctx, &pic->f);
@@ -254,7 +255,9 @@ static int alloc_frame_buffer(MpegEncContext *s, Picture *pic)
         }
     }
 
-    if (s->codec_id != AV_CODEC_ID_WMV3IMAGE && s->codec_id != AV_CODEC_ID_VC1IMAGE)
+    if (s->codec_id != AV_CODEC_ID_WMV3IMAGE &&
+        s->codec_id != AV_CODEC_ID_VC1IMAGE  &&
+        s->codec_id != AV_CODEC_ID_MSS2)
         r = ff_thread_get_buffer(s->avctx, &pic->f);
     else
         r = avcodec_default_get_buffer(s->avctx, &pic->f);

libavcodec/mss1.c

@@ -24,14 +24,13 @@
  * Microsoft Screen 1 (aka Windows Media Video V7 Screen) decoder
  */
 
-#include "libavutil/intfloat.h"
-#include "libavutil/intreadwrite.h"
 #include "avcodec.h"
 #include "mss12.h"
 
 typedef struct MSS1Context {
     MSS12Context   ctx;
     AVFrame        pic;
+    SliceContext   sc[2];
 } MSS1Context;
 
 static void arith_normalise(ArithCoder *c)
@@ -56,24 +55,11 @@ static void arith_normalise(ArithCoder *c)
         c->low   <<= 1;
         c->high  <<= 1;
         c->high   |= 1;
-        c->value  |= get_bits1(c->gb);
+        c->value  |= get_bits1(c->gbc.gb);
     }
 }
 
-static int arith_get_bit(ArithCoder *c)
-{
-    int range = c->high - c->low + 1;
-    int bit   = (((c->value - c->low) << 1) + 1) / range;
-
-    if (bit)
-        c->low += range >> 1;
-    else
-        c->high = c->low + (range >> 1) - 1;
-
-    arith_normalise(c);
-
-    return bit;
-}
+ARITH_GET_BIT()
 
 static int arith_get_bits(ArithCoder *c, int bits)
 {
@@ -118,40 +104,27 @@ static int arith_get_prob(ArithCoder *c, int *probs)
     return sym;
 }
 
-static int arith_get_model_sym(ArithCoder *c, Model *m)
-{
-    int idx, val;
-
-    idx = arith_get_prob(c, m->cum_prob);
-
-    val = m->idx2sym[idx];
-    ff_mss12_model_update(m, idx);
-
-    arith_normalise(c);
-
-    return val;
-}
+ARITH_GET_MODEL_SYM()
 
 static void arith_init(ArithCoder *c, GetBitContext *gb)
 {
-    c->low   = 0;
-    c->high  = 0xFFFF;
-    c->value = get_bits(gb, 16);
-    c->gb    = gb;
-
+    c->low           = 0;
+    c->high          = 0xFFFF;
+    c->value         = get_bits(gb, 16);
+    c->gbc.gb        = gb;
     c->get_model_sym = arith_get_model_sym;
     c->get_number    = arith_get_number;
 }
 
-static int decode_pal(MSS1Context *ctx, ArithCoder *acoder)
+static int decode_pal(MSS12Context *ctx, ArithCoder *acoder)
 {
     int i, ncol, r, g, b;
-    uint32_t *pal = ctx->ctx.pal + 256 - ctx->ctx.free_colours;
+    uint32_t *pal = ctx->pal + 256 - ctx->free_colours;
 
-    if (!ctx->ctx.free_colours)
+    if (!ctx->free_colours)
         return 0;
 
-    ncol = arith_get_number(acoder, ctx->ctx.free_colours + 1);
+    ncol = arith_get_number(acoder, ctx->free_colours + 1);
     for (i = 0; i < ncol; i++) {
         r = arith_get_bits(acoder, 8);
         g = arith_get_bits(acoder, 8);
@@ -167,7 +140,8 @@ static int mss1_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
 {
     const uint8_t *buf = avpkt->data;
     int buf_size = avpkt->size;
-    MSS1Context *c = avctx->priv_data;
+    MSS1Context *ctx = avctx->priv_data;
+    MSS12Context *c = &ctx->ctx;
     GetBitContext gb;
     ArithCoder acoder;
     int pal_changed = 0;
@@ -176,37 +150,37 @@ static int mss1_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
     init_get_bits(&gb, buf, buf_size * 8);
     arith_init(&acoder, &gb);
 
-    c->pic.reference    = 3;
-    c->pic.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE |
-                          FF_BUFFER_HINTS_REUSABLE;
-    if ((ret = avctx->reget_buffer(avctx, &c->pic)) < 0) {
+    ctx->pic.reference    = 3;
+    ctx->pic.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_READABLE |
+                            FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
+    if ((ret = avctx->reget_buffer(avctx, &ctx->pic)) < 0) {
         av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
         return ret;
     }
 
-    c->ctx.pic_start  = c->pic.data[0] + c->pic.linesize[0] * (avctx->height - 1);
-    c->ctx.pic_stride = -c->pic.linesize[0];
-    c->ctx.keyframe   = !arith_get_bit(&acoder);
-    if (c->ctx.keyframe) {
-        ff_mss12_codec_reset(&c->ctx);
-        pal_changed      = decode_pal(c, &acoder);
-        c->pic.key_frame = 1;
-        c->pic.pict_type = AV_PICTURE_TYPE_I;
+    c->pal_pic    =  ctx->pic.data[0] + ctx->pic.linesize[0] * (avctx->height - 1);
+    c->pal_stride = -ctx->pic.linesize[0];
+    c->keyframe   = !arith_get_bit(&acoder);
+    if (c->keyframe) {
+        ff_mss12_codec_reset(c);
+        pal_changed        = decode_pal(c, &acoder);
+        ctx->pic.key_frame = 1;
+        ctx->pic.pict_type = AV_PICTURE_TYPE_I;
     } else {
-        if (c->ctx.corrupted)
+        if (c->corrupted)
             return AVERROR_INVALIDDATA;
-        c->pic.key_frame = 0;
-        c->pic.pict_type = AV_PICTURE_TYPE_P;
+        ctx->pic.key_frame = 0;
+        ctx->pic.pict_type = AV_PICTURE_TYPE_P;
     }
-    c->ctx.corrupted = ff_mss12_decode_rect(&c->ctx, &acoder, 0, 0,
-                                            avctx->width, avctx->height);
-    if (c->ctx.corrupted)
+    c->corrupted = ff_mss12_decode_rect(&c->sc[0], &acoder, 0, 0,
+                                        avctx->width, avctx->height);
+    if (c->corrupted)
         return AVERROR_INVALIDDATA;
-    memcpy(c->pic.data[1], c->ctx.pal, AVPALETTE_SIZE);
-    c->pic.palette_has_changed = pal_changed;
+    memcpy(ctx->pic.data[1], c->pal, AVPALETTE_SIZE);
+    ctx->pic.palette_has_changed = pal_changed;
 
     *data_size = sizeof(AVFrame);
-    *(AVFrame*)data = c->pic;
+    *(AVFrame*)data = ctx->pic;
 
     /* always report that the buffer was completely consumed */
     return buf_size;
@@ -219,16 +193,16 @@ static av_cold int mss1_decode_init(AVCodecContext *avctx)
     c->ctx.avctx       = avctx;
     avctx->coded_frame = &c->pic;
 
-    return ff_mss12_decode_init(avctx, 0);
+    return ff_mss12_decode_init(&c->ctx, 0);
 }
 
 static av_cold int mss1_decode_end(AVCodecContext *avctx)
 {
-    MSS1Context * const c = avctx->priv_data;
+    MSS1Context * const ctx = avctx->priv_data;
 
-    if (c->pic.data[0])
-        avctx->release_buffer(avctx, &c->pic);
-    ff_mss12_decode_end(avctx);
+    if (ctx->pic.data[0])
+        avctx->release_buffer(avctx, &ctx->pic);
+    ff_mss12_decode_end(&ctx->ctx);
 
     return 0;
 }

libavcodec/mss12.h

@@ -26,8 +26,10 @@
 #ifndef AVCODEC_MSS12_H
 #define AVCODEC_MSS12_H
 
+#include "libavutil/intreadwrite.h"
 #include "avcodec.h"
 #include "get_bits.h"
+#include "bytestream.h"
 
 #define MODEL_MIN_SYMS    2
 #define MODEL_MAX_SYMS  256
@@ -46,7 +48,10 @@ typedef struct Model {
 
 typedef struct ArithCoder {
     int low, high, value;
-    GetBitContext *gb;
+    union {
+        GetBitContext *gb;
+        GetByteContext *gB;
+    } gbc;
     int (*get_model_sym)(struct ArithCoder *c, Model *m);
     int (*get_number)   (struct ArithCoder *c, int n);
 } ArithCoder;
@@ -56,28 +61,77 @@ typedef struct PixContext {
     uint8_t cache[12];
     Model cache_model, full_model;
     Model sec_models[4][8][4];
+    int special_initial_cache;
 } PixContext;
 
+struct MSS12Context;
+
+typedef struct SliceContext {
+    struct MSS12Context *c;
+    Model      intra_region, inter_region;
+    Model      pivot, edge_mode, split_mode;
+    PixContext intra_pix_ctx, inter_pix_ctx;
+} SliceContext;
+
 typedef struct MSS12Context {
     AVCodecContext *avctx;
-    uint8_t        *pic_start;
-    int            pic_stride;
-    uint8_t        *mask;
-    int            mask_linesize;
     uint32_t       pal[256];
+    uint8_t        *pal_pic;
+    uint8_t        *last_pal_pic;
+    int            pal_stride;
+    uint8_t        *mask;
+    int            mask_stride;
+    uint8_t        *rgb_pic;
+    uint8_t        *last_rgb_pic;
+    int            rgb_stride;
     int            free_colours;
     int            keyframe;
     Model          intra_region, inter_region;
     Model          pivot, edge_mode, split_mode;
     PixContext     intra_pix_ctx, inter_pix_ctx;
+    int            mvX, mvY;
     int            corrupted;
+    int            slice_split;
+    int            full_model_syms;
+    SliceContext   sc[2];
 } MSS12Context;
 
-int ff_mss12_decode_rect(MSS12Context *ctx, ArithCoder *acoder,
+int ff_mss12_decode_rect(SliceContext *ctx, ArithCoder *acoder,
                          int x, int y, int width, int height);
 void ff_mss12_model_update(Model *m, int val);
 void ff_mss12_codec_reset(MSS12Context *ctx);
-av_cold int ff_mss12_decode_init(AVCodecContext *avctx, int version);
-av_cold int ff_mss12_decode_end(AVCodecContext *avctx);
+av_cold int ff_mss12_decode_init(MSS12Context *ctx, int version);
+av_cold int ff_mss12_decode_end(MSS12Context *ctx);
+
+#define ARITH_GET_BIT(VERSION)                                          \
+static int arith ## VERSION ## _get_bit(ArithCoder *c)                  \
+{                                                                       \
+    int range = c->high - c->low + 1;                                   \
+    int bit   = (((c->value - c->low) << 1) + 1) / range;               \
+                                                                        \
+    if (bit)                                                            \
+        c->low += range >> 1;                                           \
+    else                                                                \
+        c->high = c->low + (range >> 1) - 1;                            \
+                                                                        \
+    arith ## VERSION ## _normalise(c);                                  \
+                                                                        \
+    return bit;                                                         \
+}
+
+#define ARITH_GET_MODEL_SYM(VERSION)                                    \
+static int arith ## VERSION ## _get_model_sym(ArithCoder *c, Model *m)  \
+{                                                                       \
+    int idx, val;                                                       \
+                                                                        \
+    idx = arith ## VERSION ## _get_prob(c, m->cum_prob);                \
+                                                                        \
+    val = m->idx2sym[idx];                                              \
+    ff_mss12_model_update(m, idx);                                      \
+                                                                        \
+    arith ## VERSION ## _normalise(c);                                  \
+                                                                        \
+    return val;                                                         \
+}
 
 #endif /* AVCODEC_MSS12_H */

libavcodec/mss2dsp.c

+/*
+ * Microsoft Screen 2 (aka Windows Media Video V9 Screen) decoder
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * Microsoft Screen 2 (aka Windows Media Video V9 Screen) decoder DSP routines
+ */
+
+#include "mss2dsp.h"
+#include "libavutil/common.h"
+
+static av_always_inline void mss2_blit_wmv9_template(uint8_t *dst,
+                                                     int dst_stride,
+                                                     int gray,
+                                                     int use_mask,
+                                                     int maskcolor,
+                                                     const uint8_t *mask,
+                                                     int mask_stride,
+                                                     const uint8_t *srcy,
+                                                     int srcy_stride,
+                                                     const uint8_t *srcu,
+                                                     const uint8_t *srcv,
+                                                     int srcuv_stride,
+                                                     int w, int h)
+{
+    int i, j, k, r = -1;
+    while (++r < h) {
+        for (i = 0, j = 0, k = 0; i < w; j += (i & 1), i++, k += 3) {
+            if (!use_mask || mask[i] == maskcolor) {
+                if (gray) {
+                    dst[k] = dst[k + 1] = dst[k + 2] = 0x80;
+                } else {
+                    int y = srcy[i];
+                    int u = srcu[j] - 128;
+                    int v = srcv[j] - 128;
+                    dst[k]     = av_clip_uint8(y + (             91881 * v + 32768 >> 16));
+                    dst[k + 1] = av_clip_uint8(y + (-22554 * u - 46802 * v + 32768 >> 16));
+                    dst[k + 2] = av_clip_uint8(y + (116130 * u             + 32768 >> 16));
+                }
+            }
+        }
+        mask +=  mask_stride;
+        dst  +=   dst_stride;
+        srcy +=  srcy_stride;
+        srcu += srcuv_stride * (r & 1);
+        srcv += srcuv_stride * (r & 1);
+    }
+}
+
+static void mss2_blit_wmv9_c(uint8_t *dst, int dst_stride,
+                             const uint8_t *srcy, int srcy_stride,
+                             const uint8_t *srcu, const uint8_t *srcv,
+                             int srcuv_stride, int w, int h)
+{
+    mss2_blit_wmv9_template(dst, dst_stride, 0, 0,
+                            0, NULL, 0,
+                            srcy, srcy_stride,
+                            srcu, srcv, srcuv_stride,
+                            w, h);
+}
+
+static void mss2_blit_wmv9_masked_c(uint8_t *dst, int dst_stride,
+                                    int maskcolor, const uint8_t *mask,
+                                    int mask_stride,
+                                    const uint8_t *srcy, int srcy_stride,
+                                    const uint8_t *srcu, const uint8_t *srcv,
+                                    int srcuv_stride, int w, int h)
+{
+    mss2_blit_wmv9_template(dst, dst_stride, 0, 1,
+                            maskcolor, mask, mask_stride,
+                            srcy, srcy_stride,
+                            srcu, srcv, srcuv_stride,
+                            w, h);
+}
+
+static void mss2_gray_fill_masked_c(uint8_t *dst, int dst_stride,
+                                    int maskcolor, const uint8_t *mask,
+                                    int mask_stride, int w, int h)
+{
+    mss2_blit_wmv9_template(dst, dst_stride, 1, 1,
+                            maskcolor, mask, mask_stride,
+                            NULL, 0,
+                            NULL, NULL, 0,
+                            w, h);
+}
+
+static void upsample_plane_c(uint8_t *plane, int plane_stride, int w, int h)
+{
+    uint8_t *src1, *src2, *dst1, *dst2, *p, a, b;
+    int i, j;
+
+    w += (w & 1);
+    h += (h & 1);
+
+    j = h - 1;
+
+    memcpy(plane + plane_stride *  j,
+           plane + plane_stride * (j >> 1),
+           w);
+
+    while ((j -= 2) > 0) {
+        dst1 = plane + plane_stride *  (j + 1);
+        dst2 = plane + plane_stride *   j;
+        src1 = plane + plane_stride * ((j + 1) >> 1);
+        src2 = plane + plane_stride * ( j      >> 1);
+
+        for (i = (w - 1) >> 1; i >= 0; i--) {
+            a = src1[i];
+            b = src2[i];
+            dst1[i] = (3 * a + b + 2) >> 2;
+            dst2[i] = (a + 3 * b + 2) >> 2;
+        }
+    }
+
+    for (j = h - 1; j >= 0; j--) {
+        p = plane + plane_stride * j;
+        i = w - 1;
+
+        p[i] = p[i >> 1];
+
+        while ((i -= 2) > 0) {
+            a = p[ i      >> 1];
+            b = p[(i + 1) >> 1];
+            p[i]     = (3 * a + b + 1) >> 2;
+            p[i + 1] = (a + 3 * b + 1) >> 2;
+        }
+    }
+}
+
+av_cold void ff_mss2dsp_init(MSS2DSPContext* dsp)
+{
+    dsp->mss2_blit_wmv9        = mss2_blit_wmv9_c;
+    dsp->mss2_blit_wmv9_masked = mss2_blit_wmv9_masked_c;
+    dsp->mss2_gray_fill_masked = mss2_gray_fill_masked_c;
+    dsp->upsample_plane        = upsample_plane_c;
+}

libavcodec/mss2dsp.h

+/*
+ * Microsoft Screen 2 (aka Windows Media Video V9 Screen) decoder
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * Microsoft Screen 2 (aka Windows Media Video V9 Screen) decoder DSP routines
+ */
+
+#ifndef AVCODEC_MSS2DSP_H
+#define AVCODEC_MSS2DSP_H
+
+#include "dsputil.h"
+
+typedef struct MSS2DSPContext {
+    void (*mss2_blit_wmv9)(uint8_t *dst, int dst_stride,
+                           const uint8_t *srcy, int srcy_stride,
+                           const uint8_t *srcu, const uint8_t *srcv,
+                           int srcuv_stride, int w, int h);
+    void (*mss2_blit_wmv9_masked)(uint8_t *dst, int dst_stride,
+                                  int maskcolor, const uint8_t *mask,
+                                  int mask_stride,
+                                  const uint8_t *srcy, int srcy_stride,
+                                  const uint8_t *srcu, const uint8_t *srcv,
+                                  int srcuv_stride, int w, int h);
+    void (*mss2_gray_fill_masked)(uint8_t *dst, int dst_stride,
+                                  int maskcolor, const uint8_t *mask,
+                                  int mask_stride, int w, int h);
+    void (*upsample_plane)(uint8_t *plane, int plane_stride, int w, int h);
+} MSS2DSPContext;
+
+av_cold void ff_mss2dsp_init(MSS2DSPContext* dsp);
+
+#endif /* AVCODEC_MSS2DSP_H */

libavcodec/vc1.c

@@ -578,7 +578,12 @@ int ff_vc1_parse_frame_header(VC1Context *v, GetBitContext* gb)
 
     if (v->finterpflag)
         v->interpfrm = get_bits1(gb);
-    skip_bits(gb, 2); //framecnt unused
+    if (v->s.avctx->codec->id == AV_CODEC_ID_MSS2)
+        v->respic   =
+        v->rangered =
+        v->multires = get_bits(gb, 2) == 1;
+    else
+        skip_bits(gb, 2); //framecnt unused
     v->rangeredfrm = 0;
     if (v->rangered)
         v->rangeredfrm = get_bits1(gb);

libavcodec/vc1.h

@@ -394,6 +394,8 @@ typedef struct VC1Context{
     uint8_t broken_link;         ///< Broken link flag (BROKEN_LINK syntax element)
     uint8_t closed_entry;        ///< Closed entry point flag (CLOSED_ENTRY syntax element)
 
+    int end_mb_x;                ///< Horizontal macroblock limit (used only by mss2)
+
     int parse_only;              ///< Context is used within parser
 
     int warn_interlaced;

libavcodec/vc1dec.c

@@ -4348,10 +4348,10 @@ static void vc1_decode_i_blocks(VC1Context *v)
     s->mb_x = s->mb_y = 0;
     s->mb_intra         = 1;
     s->first_slice_line = 1;
-    for (s->mb_y = 0; s->mb_y < s->mb_height; s->mb_y++) {
+    for (s->mb_y = 0; s->mb_y < s->end_mb_y; s->mb_y++) {
         s->mb_x = 0;
         ff_init_block_index(s);
-        for (; s->mb_x < s->mb_width; s->mb_x++) {
+        for (; s->mb_x < v->end_mb_x; s->mb_x++) {
             uint8_t *dst[6];
             ff_update_block_index(s);
             dst[0] = s->dest[0];
@@ -4438,7 +4438,10 @@ static void vc1_decode_i_blocks(VC1Context *v)
         s->first_slice_line = 0;
     }
     if (v->s.loop_filter)
-        ff_draw_horiz_band(s, (s->mb_height - 1) * 16, 16);
+        ff_draw_horiz_band(s, (s->end_mb_y - 1) * 16, 16);
+
+    /* This is intentionally mb_height and not end_mb_y - unlike in advanced
+     * profile, these only differ are when decoding MSS2 rectangles. */
     ff_er_add_slice(s, 0, 0, s->mb_width - 1, s->mb_height - 1, ER_MB_END);
 }
 
@@ -5549,6 +5552,7 @@ static int vc1_decode_frame(AVCodecContext *avctx, void *data,
         ff_er_frame_start(s);
 
         v->bits = buf_size * 8;
+        v->end_mb_x = s->mb_width;
         if (v->field_mode) {
             uint8_t *tmp[2];
             s->current_picture.f.linesize[0] <<= 1;

libavcodec/version.h

@@ -27,8 +27,8 @@
  */
 
 #define LIBAVCODEC_VERSION_MAJOR 54
-#define LIBAVCODEC_VERSION_MINOR 26
-#define LIBAVCODEC_VERSION_MICRO  1
+#define LIBAVCODEC_VERSION_MINOR 27
+#define LIBAVCODEC_VERSION_MICRO  0
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
                                                LIBAVCODEC_VERSION_MINOR, \

libavformat/riff.c

@@ -289,6 +289,7 @@ const AVCodecTag ff_codec_bmp_tags[] = {
     { AV_CODEC_ID_TSCC2,        MKTAG('T', 'S', 'C', '2') },
     { AV_CODEC_ID_MTS2,         MKTAG('M', 'T', 'S', '2') },
     { AV_CODEC_ID_CLLC,         MKTAG('C', 'L', 'L', 'C') },
+    { AV_CODEC_ID_MSS2,         MKTAG('M', 'S', 'S', '2') },
     { AV_CODEC_ID_NONE,         0 }
 };