Add frame buffer allocators. aka simplify calls to

AVCodecContext.{get,release}_buffer().

Originally committed as revision 17804 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/mpegvideo.c

@@ -164,6 +164,43 @@ void ff_copy_picture(Picture *dst, Picture *src){
     dst->type= FF_BUFFER_TYPE_COPY;
 }
 
+/**
+ * Releases a frame buffer
+ */
+static void free_frame_buffer(MpegEncContext *s, Picture *pic)
+{
+    s->avctx->release_buffer(s->avctx, (AVFrame*)pic);
+}
+
+/**
+ * Allocates a frame buffer
+ */
+static int alloc_frame_buffer(MpegEncContext *s, Picture *pic)
+{
+    int r;
+
+    r = s->avctx->get_buffer(s->avctx, (AVFrame*)pic);
+
+    if (r<0 || !pic->age || !pic->type || !pic->data[0]) {
+        av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed (%d %d %d %p)\n", r, pic->age, pic->type, pic->data[0]);
+        return -1;
+    }
+
+    if (s->linesize && (s->linesize != pic->linesize[0] || s->uvlinesize != pic->linesize[1])) {
+        av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed (stride changed)\n");
+        free_frame_buffer(s, pic);
+        return -1;
+    }
+
+    if (pic->linesize[1] != pic->linesize[2]) {
+        av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed (uv stride mismatch)\n");
+        free_frame_buffer(s, pic);
+        return -1;
+    }
+
+    return 0;
+}
+
 /**
  * allocates a Picture
  * The pixels are allocated/set by calling get_buffer() if shared=0
@@ -183,24 +220,8 @@ int alloc_picture(MpegEncContext *s, Picture *pic, int shared){
     }else{
         assert(!pic->data[0]);
 
-        r= s->avctx->get_buffer(s->avctx, (AVFrame*)pic);
-
-        if(r<0 || !pic->age || !pic->type || !pic->data[0]){
-            av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed (%d %d %d %p)\n", r, pic->age, pic->type, pic->data[0]);
-            return -1;
-        }
-
-        if(s->linesize && (s->linesize != pic->linesize[0] || s->uvlinesize != pic->linesize[1])){
-            av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed (stride changed)\n");
-            s->avctx->release_buffer(s->avctx, (AVFrame*)pic);
-            return -1;
-        }
-
-        if(pic->linesize[1] != pic->linesize[2]){
-            av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed (uv stride mismatch)\n");
-            s->avctx->release_buffer(s->avctx, (AVFrame*)pic);
+        if (alloc_frame_buffer(s, pic) < 0)
             return -1;
-        }
 
         s->linesize  = pic->linesize[0];
         s->uvlinesize= pic->linesize[1];
@@ -249,7 +270,7 @@ int alloc_picture(MpegEncContext *s, Picture *pic, int shared){
     return 0;
 fail: //for the CHECKED_ALLOCZ macro
     if(r>=0)
-        s->avctx->release_buffer(s->avctx, (AVFrame*)pic);
+        free_frame_buffer(s, pic);
     return -1;
 }
 
@@ -260,7 +281,7 @@ static void free_picture(MpegEncContext *s, Picture *pic){
     int i;
 
     if(pic->data[0] && pic->type!=FF_BUFFER_TYPE_SHARED){
-        s->avctx->release_buffer(s->avctx, (AVFrame*)pic);
+        free_frame_buffer(s, pic);
     }
 
     av_freep(&pic->mb_var);
@@ -839,7 +860,7 @@ int MPV_frame_start(MpegEncContext *s, AVCodecContext *avctx)
     /* mark&release old frames */
     if (s->pict_type != FF_B_TYPE && s->last_picture_ptr && s->last_picture_ptr != s->next_picture_ptr && s->last_picture_ptr->data[0]) {
       if(s->out_format != FMT_H264 || s->codec_id == CODEC_ID_SVQ3){
-        avctx->release_buffer(avctx, (AVFrame*)s->last_picture_ptr);
+          free_frame_buffer(s, s->last_picture_ptr);
 
         /* release forgotten pictures */
         /* if(mpeg124/h263) */
@@ -847,7 +868,7 @@ int MPV_frame_start(MpegEncContext *s, AVCodecContext *avctx)
             for(i=0; i<MAX_PICTURE_COUNT; i++){
                 if(s->picture[i].data[0] && &s->picture[i] != s->next_picture_ptr && s->picture[i].reference){
                     av_log(avctx, AV_LOG_ERROR, "releasing zombie picture\n");
-                    avctx->release_buffer(avctx, (AVFrame*)&s->picture[i]);
+                    free_frame_buffer(s, &s->picture[i]);
                 }
             }
         }
@@ -858,7 +879,7 @@ alloc:
         /* release non reference frames */
         for(i=0; i<MAX_PICTURE_COUNT; i++){
             if(s->picture[i].data[0] && !s->picture[i].reference /*&& s->picture[i].type!=FF_BUFFER_TYPE_SHARED*/){
-                s->avctx->release_buffer(s->avctx, (AVFrame*)&s->picture[i]);
+                free_frame_buffer(s, &s->picture[i]);
             }
         }
 
@@ -996,7 +1017,7 @@ void MPV_frame_end(MpegEncContext *s)
         /* release non-reference frames */
         for(i=0; i<MAX_PICTURE_COUNT; i++){
             if(s->picture[i].data[0] && !s->picture[i].reference /*&& s->picture[i].type!=FF_BUFFER_TYPE_SHARED*/){
-                s->avctx->release_buffer(s->avctx, (AVFrame*)&s->picture[i]);
+                free_frame_buffer(s, &s->picture[i]);
             }
         }
     }
@@ -2068,7 +2089,7 @@ void ff_mpeg_flush(AVCodecContext *avctx){
     for(i=0; i<MAX_PICTURE_COUNT; i++){
        if(s->picture[i].data[0] && (   s->picture[i].type == FF_BUFFER_TYPE_INTERNAL
                                     || s->picture[i].type == FF_BUFFER_TYPE_USER))
-        avctx->release_buffer(avctx, (AVFrame*)&s->picture[i]);
+        free_frame_buffer(s, &s->picture[i]);
     }
     s->current_picture_ptr = s->last_picture_ptr = s->next_picture_ptr = NULL;