mpegvideo: move vol_control_parameters to the only place it is used

Signed-off-by: Diego Biurrun <diego@biurrun.de>

libavcodec/mpeg4video.h

@@ -94,6 +94,8 @@ typedef struct Mpeg4DecContext {
     int lavc_build;
     ///< flag for having shown the warning about divxs invalid b frames
     int showed_packed_warning;
+    int vol_control_parameters; /**< does the stream contain the low_delay flag,
+                                 *   used to work around buggy encoders. */
 
     int cplx_estimation_trash_i;
     int cplx_estimation_trash_p;

libavcodec/mpeg4videodec.c

@@ -1685,7 +1685,7 @@ static int decode_vol_header(Mpeg4DecContext *ctx, GetBitContext *gb)
         s->avctx->sample_aspect_ratio = ff_h263_pixel_aspect[s->aspect_ratio_info];
     }
 
-    if ((s->vol_control_parameters = get_bits1(gb))) { /* vol control parameter */
+    if ((ctx->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");
@@ -2058,7 +2058,7 @@ static int decode_user_data(Mpeg4DecContext *ctx, GetBitContext *gb)
 
     if (ctx->xvid_build == -1 && ctx->divx_version == -1 && ctx->lavc_build == -1)
         if (s->codec_tag == AV_RL32("DIVX") && s->vo_type == 0 &&
-            s->vol_control_parameters == 0)
+            ctx->vol_control_parameters == 0)
             ctx->divx_version = 400;  // divx 4
 
     if (ctx->xvid_build >= 0 && ctx->divx_version >= 0) {
@@ -2085,7 +2085,7 @@ static int decode_vop_header(Mpeg4DecContext *ctx, GetBitContext *gb)
 
     s->pict_type = get_bits(gb, 2) + AV_PICTURE_TYPE_I;        /* pict type: I = 0 , P = 1 */
     if (s->pict_type == AV_PICTURE_TYPE_B && s->low_delay &&
-        s->vol_control_parameters == 0 && !(s->flags & CODEC_FLAG_LOW_DELAY)) {
+        ctx->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;
     }
@@ -2276,7 +2276,7 @@ static int decode_vop_header(Mpeg4DecContext *ctx, GetBitContext *gb)
                    s->data_partitioning, ctx->resync_marker,
                    ctx->num_sprite_warping_points, s->sprite_warping_accuracy,
                    1 - s->no_rounding, s->vo_type,
-                   s->vol_control_parameters ? " VOLC" : " ", ctx->intra_dc_threshold,
+                   ctx->vol_control_parameters ? " VOLC" : " ", ctx->intra_dc_threshold,
                    ctx->cplx_estimation_trash_i, ctx->cplx_estimation_trash_p,
                    ctx->cplx_estimation_trash_b);
         }
@@ -2297,7 +2297,7 @@ static int decode_vop_header(Mpeg4DecContext *ctx, GetBitContext *gb)
     /* 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 &&
+    if (s->vo_type == 0 && ctx->vol_control_parameters == 0 &&
         ctx->divx_version == -1 && s->picture_number == 0) {
         av_log(s->avctx, AV_LOG_WARNING,
                "looks like this file was encoded with (divx4/(old)xvid/opendivx) -> forcing low_delay flag\n");

libavcodec/mpegvideo.h

@@ -518,7 +518,6 @@ typedef struct MpegEncContext {
     int partitioned_frame;           ///< is current frame partitioned
     int low_delay;                   ///< no reordering needed / has no b-frames
     int vo_type;
-    int vol_control_parameters;      ///< does the stream contain the low_delay flag, used to workaround buggy encoders
     PutBitContext tex_pb;            ///< used for data partitioned VOPs
     PutBitContext pb2;               ///< used for data partitioned VOPs
     int mpeg_quant;