avcodec: deprecate AVFrame.age

This was intended as an optimisation for skipped blocks in MPEG2
P-frames and never used elsewhere.  Removing this "optimisation"
speeds up MPEG2 decoding by 1-2% (ARM Cortex-A9).
Signed-off-by: Mans Rullgard <mans@mansr.com>

avplay.c

@@ -1564,7 +1564,6 @@ static int input_get_buffer(AVCodecContext *codec, AVFrame *pic)
         pic->linesize[i] = ref->linesize[i];
     }
     pic->opaque = ref;
-    pic->age    = INT_MAX;
     pic->type   = FF_BUFFER_TYPE_USER;
     pic->reordered_opaque = codec->reordered_opaque;
     if(codec->pkt) pic->pkt_pts = codec->pkt->pts;

doc/APIchanges

@@ -13,6 +13,9 @@ libavutil:   2011-04-18
 
 API changes, most recent first:
 
+2011-12-18 - xxxxxxx - lavc 53.28.1
+  Deprecate AVFrame.age. The field is unused.
+
 2011-xx-xx - xxxxxxx - lavf 53.17.0
   Add avformat_open_input().
   Deprecate av_close_input_file() and av_close_input_stream().

libavcodec/avcodec.h

@@ -1004,13 +1004,12 @@ typedef struct AVFrame {
      */
     int quality;
 
+#if FF_API_AVFRAME_AGE
     /**
-     * buffer age (1->was last buffer and dint change, 2->..., ...).
-     * Set to INT_MAX if the buffer has not been used yet.
-     * - encoding: unused
-     * - decoding: MUST be set by get_buffer() for video.
+     * @deprecated unused
      */
-    int age;
+    attribute_deprecated int age;
+#endif
 
     /**
      * is this picture used as reference

libavcodec/internal.h

@@ -30,7 +30,6 @@
 #include "avcodec.h"
 
 typedef struct InternalBuffer {
-    int last_pic_num;
     uint8_t *base[AV_NUM_DATA_POINTERS];
     uint8_t *data[AV_NUM_DATA_POINTERS];
     int linesize[AV_NUM_DATA_POINTERS];

libavcodec/mpegvideo.c

@@ -263,9 +263,9 @@ static int alloc_frame_buffer(MpegEncContext *s, Picture *pic)
     else
         r = avcodec_default_get_buffer(s->avctx, (AVFrame *) pic);
 
-    if (r < 0 || !pic->f.age || !pic->f.type || !pic->f.data[0]) {
-        av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed (%d %d %d %p)\n",
-               r, pic->f.age, pic->f.type, pic->f.data[0]);
+    if (r < 0 || !pic->f.type || !pic->f.data[0]) {
+        av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed (%d %d %p)\n",
+               r, pic->f.type, pic->f.data[0]);
         av_freep(&pic->f.hwaccel_picture_private);
         return -1;
     }
@@ -369,15 +369,6 @@ int ff_alloc_picture(MpegEncContext *s, Picture *pic, int shared)
                           1 * sizeof(AVPanScan), fail)
     }
 
-    /* It might be nicer if the application would keep track of these
-     * but it would require an API change. */
-    memmove(s->prev_pict_types + 1, s->prev_pict_types,
-            PREV_PICT_TYPES_BUFFER_SIZE-1);
-    s->prev_pict_types[0] =  s->dropable ? AV_PICTURE_TYPE_B : s->pict_type;
-    if (pic->f.age < PREV_PICT_TYPES_BUFFER_SIZE &&
-        s->prev_pict_types[pic->f.age] == AV_PICTURE_TYPE_B)
-        pic->f.age = INT_MAX; // Skipped MBs in B-frames are quite rare in MPEG-1/2
-                              // and it is a bit tricky to skip them anyway.
     pic->owner2 = s;
 
     return 0;
@@ -574,9 +565,6 @@ int ff_mpeg_update_thread_context(AVCodecContext *dst,
     s->current_picture_ptr = REBASE_PICTURE(s1->current_picture_ptr, s, s1);
     s->next_picture_ptr    = REBASE_PICTURE(s1->next_picture_ptr,    s, s1);
 
-    memcpy(s->prev_pict_types, s1->prev_pict_types,
-           PREV_PICT_TYPES_BUFFER_SIZE);
-
     // Error/bug resilience
     s->next_p_frame_damaged = s1->next_p_frame_damaged;
     s->workaround_bugs      = s1->workaround_bugs;
@@ -880,8 +868,6 @@ av_cold int MPV_common_init(MpegEncContext *s)
         /* init macroblock skip table */
         FF_ALLOCZ_OR_GOTO(s->avctx, s->mbskip_table, mb_array_size + 2, fail);
         // Note the + 1 is for  a quicker mpeg4 slice_end detection
-        FF_ALLOCZ_OR_GOTO(s->avctx, s->prev_pict_types,
-                          PREV_PICT_TYPES_BUFFER_SIZE, fail);
 
         s->parse_context.state = -1;
         if ((s->avctx->debug & (FF_DEBUG_VIS_QP | FF_DEBUG_VIS_MB_TYPE)) ||
@@ -981,7 +967,6 @@ void MPV_common_end(MpegEncContext *s)
     av_freep(&s->pred_dir_table);
 
     av_freep(&s->mbskip_table);
-    av_freep(&s->prev_pict_types);
     av_freep(&s->bitstream_buffer);
     s->allocated_bitstream_buffer_size = 0;
 
@@ -2215,24 +2200,13 @@ void MPV_decode_mb_internal(MpegEncContext *s, DCTELEM block[12][64],
         /* skip only during decoding as we might trash the buffers during encoding a bit */
         if(!s->encoding){
             uint8_t *mbskip_ptr = &s->mbskip_table[mb_xy];
-            const int age = s->current_picture.f.age;
-
-            assert(age);
 
             if (s->mb_skipped) {
                 s->mb_skipped= 0;
                 assert(s->pict_type!=AV_PICTURE_TYPE_I);
-
-                (*mbskip_ptr) ++; /* indicate that this time we skipped it */
-                if(*mbskip_ptr >99) *mbskip_ptr= 99;
-
-                /* if previous was skipped too, then nothing to do !  */
-                if (*mbskip_ptr >= age && s->current_picture.f.reference){
-                    return;
-                }
+                *mbskip_ptr = 1;
             } else if(!s->current_picture.f.reference) {
-                (*mbskip_ptr) ++; /* increase counter so the age can be compared cleanly */
-                if(*mbskip_ptr >99) *mbskip_ptr= 99;
+                *mbskip_ptr = 1;
             } else{
                 *mbskip_ptr = 0; /* not skipped */
             }

libavcodec/mpegvideo.h

@@ -309,8 +309,6 @@ typedef struct MpegEncContext {
     uint8_t *coded_block;          ///< used for coded block pattern prediction (msmpeg4v3, wmv1)
     int16_t (*ac_val_base)[16];
     int16_t (*ac_val[3])[16];      ///< used for for mpeg4 AC prediction, all 3 arrays must be continuous
-    uint8_t *prev_pict_types;     ///< previous picture types in bitstream order, used for mb skip
-#define PREV_PICT_TYPES_BUFFER_SIZE 256
     int mb_skipped;                ///< MUST BE SET only during DECODING
     uint8_t *mbskip_table;        /**< used to avoid copy if macroblock skipped (for black regions for example)
                                    and used for b-frame encoding & decoding (contains skip table of next P Frame) */

libavcodec/pthread.c

@@ -855,13 +855,6 @@ int ff_thread_get_buffer(AVCodecContext *avctx, AVFrame *f)
 
     pthread_mutex_unlock(&p->parent->buffer_mutex);
 
-    /*
-     * Buffer age is difficult to keep track of between
-     * multiple threads, and the optimizations it allows
-     * are not worth the effort. It is disabled for now.
-     */
-    f->age = INT_MAX;
-
     return err;
 }
 

libavcodec/utils.c

@@ -346,7 +346,6 @@ static int video_get_buffer(AVCodecContext *s, AVFrame *pic)
     int w= s->width;
     int h= s->height;
     InternalBuffer *buf;
-    int *picture_number;
     AVCodecInternal *avci = s->internal;
 
     if(pic->data[0]!=NULL) {
@@ -367,8 +366,6 @@ static int video_get_buffer(AVCodecContext *s, AVFrame *pic)
     }
 
     buf = &avci->buffer[avci->buffer_count];
-    picture_number = &(avci->buffer[INTERNAL_BUFFER_SIZE]).last_pic_num; //FIXME ugly hack
-    (*picture_number)++;
 
     if(buf->base[0] && (buf->width != w || buf->height != h || buf->pix_fmt != s->pix_fmt)){
         if(s->active_thread_type&FF_THREAD_FRAME) {
@@ -382,10 +379,7 @@ static int video_get_buffer(AVCodecContext *s, AVFrame *pic)
         }
     }
 
-    if(buf->base[0]){
-        pic->age= *picture_number - buf->last_pic_num;
-        buf->last_pic_num= *picture_number;
-    }else{
+    if (!buf->base[0]) {
         int h_chroma_shift, v_chroma_shift;
         int size[4] = {0};
         int tmpsize;
@@ -424,7 +418,6 @@ static int video_get_buffer(AVCodecContext *s, AVFrame *pic)
             size[i] = picture.data[i+1] - picture.data[i];
         size[i] = tmpsize - (picture.data[i] - picture.data[0]);
 
-        buf->last_pic_num= -256*256*256*64;
         memset(buf->base, 0, sizeof(buf->base));
         memset(buf->data, 0, sizeof(buf->data));
 
@@ -453,7 +446,6 @@ static int video_get_buffer(AVCodecContext *s, AVFrame *pic)
         buf->width  = s->width;
         buf->height = s->height;
         buf->pix_fmt= s->pix_fmt;
-        pic->age= 256*256*256*64;
     }
     pic->type= FF_BUFFER_TYPE_INTERNAL;
 

libavcodec/version.h

@@ -22,7 +22,7 @@
 
 #define LIBAVCODEC_VERSION_MAJOR 53
 #define LIBAVCODEC_VERSION_MINOR 28
-#define LIBAVCODEC_VERSION_MICRO  0
+#define LIBAVCODEC_VERSION_MICRO  1
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
                                                LIBAVCODEC_VERSION_MINOR, \
@@ -116,5 +116,8 @@
 #ifndef FF_API_OLD_DECODE_AUDIO
 #define FF_API_OLD_DECODE_AUDIO (LIBAVCODEC_VERSION_MAJOR < 54)
 #endif
+#ifndef FF_API_AVFRAME_AGE
+#define FF_API_AVFRAME_AGE (LIBAVCODEC_VERSION_MAJOR < 54)
+#endif
 
 #endif /* AVCODEC_VERSION_H */