vc1: use the AVFrame API properly.

libavcodec/vc1.h

@@ -380,7 +380,7 @@ typedef struct VC1Context{
     //@{
     int new_sprite;
     int two_sprites;
-    AVFrame sprite_output_frame;
+    AVFrame *sprite_output_frame;
     int output_width, output_height, sprite_width, sprite_height;
     uint8_t* sr_rows[2][2];      ///< Sprite resizer line cache
     //@}

libavcodec/vc1dec.c

@@ -5364,8 +5364,8 @@ static void vc1_draw_sprites(VC1Context *v, SpriteData* sd)
         int width = v->output_width>>!!plane;
 
         for (row = 0; row < v->output_height>>!!plane; row++) {
-            uint8_t *dst = v->sprite_output_frame.data[plane] +
-                           v->sprite_output_frame.linesize[plane] * row;
+            uint8_t *dst = v->sprite_output_frame->data[plane] +
+                           v->sprite_output_frame->linesize[plane] * row;
 
             for (sprite = 0; sprite <= v->two_sprites; sprite++) {
                 uint8_t *iplane = s->current_picture.f.data[plane];
@@ -5455,8 +5455,8 @@ static int vc1_decode_sprites(VC1Context *v, GetBitContext* gb)
         v->two_sprites = 0;
     }
 
-    av_frame_unref(&v->sprite_output_frame);
-    if (ff_get_buffer(avctx, &v->sprite_output_frame, 0) < 0) {
+    av_frame_unref(v->sprite_output_frame);
+    if (ff_get_buffer(avctx, v->sprite_output_frame, 0) < 0) {
         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
         return -1;
     }
@@ -5673,6 +5673,10 @@ static av_cold int vc1_decode_init(AVCodecContext *avctx)
         v->res_sprite = (avctx->codec_id == AV_CODEC_ID_VC1IMAGE);
     }
 
+    v->sprite_output_frame = av_frame_alloc();
+    if (!v->sprite_output_frame)
+        return AVERROR(ENOMEM);
+
     avctx->profile = v->profile;
     if (v->profile == PROFILE_ADVANCED)
         avctx->level = v->level;
@@ -5714,7 +5718,7 @@ av_cold int ff_vc1_decode_end(AVCodecContext *avctx)
     VC1Context *v = avctx->priv_data;
     int i;
 
-    av_frame_unref(&v->sprite_output_frame);
+    av_frame_free(&v->sprite_output_frame);
 
     for (i = 0; i < 4; i++)
         av_freep(&v->sr_rows[i >> 1][i & 1]);
@@ -6085,7 +6089,7 @@ image:
         if (vc1_decode_sprites(v, &s->gb))
             goto err;
 #endif
-        if ((ret = av_frame_ref(pict, &v->sprite_output_frame)) < 0)
+        if ((ret = av_frame_ref(pict, v->sprite_output_frame)) < 0)
             goto err;
         *got_frame = 1;
     } else {