lavc: deprecate the use of AVCodecContext.time_base for decoding

When decoding, this field holds the inverse of the framerate that can be
written in the headers for some codecs. Using a field called 'time_base'
for this is very misleading, as there are no timestamps associated with
it. Furthermore, this field is used for a very different purpose during
encoding.

Add a new field, called 'framerate', to replace the use of time_base for
decoding.

1 files changed, 9 insertions, 10 deletions

diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c
index 3adf0cf44e..ff3782647d 100644
--- a/libavcodec/mpeg4videodec.c
+++ b/libavcodec/mpeg4videodec.c
@@ -1722,23 +1722,22 @@ static int decode_vol_header(Mpeg4DecContext *ctx, GetBitContext *gb)
 
     check_marker(gb, "before time_increment_resolution");
 
-    s->avctx->time_base.den = get_bits(gb, 16);
-    if (!s->avctx->time_base.den) {
-        av_log(s->avctx, AV_LOG_ERROR, "time_base.den==0\n");
-        s->avctx->time_base.num = 0;
+    s->avctx->framerate.num = get_bits(gb, 16);
+    if (!s->avctx->framerate.num) {
+        av_log(s->avctx, AV_LOG_ERROR, "framerate==0\n");
         return -1;
     }
 
-    ctx->time_increment_bits = av_log2(s->avctx->time_base.den - 1) + 1;
+    ctx->time_increment_bits = av_log2(s->avctx->framerate.num - 1) + 1;
     if (ctx->time_increment_bits < 1)
         ctx->time_increment_bits = 1;
 
     check_marker(gb, "before fixed_vop_rate");
 
     if (get_bits1(gb) != 0)     /* fixed_vop_rate  */
-        s->avctx->time_base.num = get_bits(gb, ctx->time_increment_bits);
+        s->avctx->framerate.den = get_bits(gb, ctx->time_increment_bits);
     else
-        s->avctx->time_base.num = 1;
+        s->avctx->framerate.den = 1;
 
     ctx->t_frame = 0;
 
@@ -2126,19 +2125,19 @@ static int decode_vop_header(Mpeg4DecContext *ctx, GetBitContext *gb)
     if (s->pict_type != AV_PICTURE_TYPE_B) {
         s->last_time_base = s->time_base;
         s->time_base     += time_incr;
-        s->time = s->time_base * s->avctx->time_base.den + time_increment;
+        s->time = s->time_base * s->avctx->framerate.num + time_increment;
         if (s->workaround_bugs & FF_BUG_UMP4) {
             if (s->time < s->last_non_b_time) {
                 /* header is not mpeg-4-compatible, broken encoder,
                  * trying to workaround */
                 s->time_base++;
-                s->time += s->avctx->time_base.den;
+                s->time += s->avctx->framerate.num;
             }
         }
         s->pp_time         = s->time - s->last_non_b_time;
         s->last_non_b_time = s->time;
     } else {
-        s->time    = (s->last_time_base + time_incr) * s->avctx->time_base.den + time_increment;
+        s->time    = (s->last_time_base + time_incr) * s->avctx->framerate.num + time_increment;
         s->pb_time = s->pp_time - (s->last_non_b_time - s->time);
         if (s->pp_time <= s->pb_time ||
             s->pp_time <= s->pp_time - s->pb_time ||