[FFmpeg-cvslog] vc1: don't read the interpfrm and bfraction elements for interlaced frames

[Hendrik Leppkes]

ffmpeg | branch: master | Hendrik Leppkes <h.leppkes at gmail.com> | Fri Jan 13 18:41:21 2012 +0100| [7662a532fbb83d5b3e559a7da58254e56cae3157] | committer: Kostya Shishkov

vc1: don't read the interpfrm and bfraction elements for interlaced frames

This matches the spec as well as the reference decoder, and fixes a bug
with interlaced frame decoding.

Signed-off-by: Kostya Shishkov <kostya.shishkov at gmail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=7662a532fbb83d5b3e559a7da58254e56cae3157
---

 libavcodec/vc1.c |   16 +++++++++-------
 1 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/libavcodec/vc1.c b/libavcodec/vc1.c
index d728f9b..0a70062 100644
--- a/libavcodec/vc1.c
+++ b/libavcodec/vc1.c
@@ -911,13 +911,15 @@ int vc1_parse_frame_header_adv(VC1Context *v, GetBitContext* gb)
         }
         goto parse_common_info;
     }
-    if (v->finterpflag)
-        v->interpfrm = get_bits1(gb);
-    if (v->s.pict_type == AV_PICTURE_TYPE_B) {
-        v->bfraction_lut_index = get_vlc2(gb, ff_vc1_bfraction_vlc.table, VC1_BFRACTION_VLC_BITS, 1);
-        v->bfraction           = ff_vc1_bfraction_lut[v->bfraction_lut_index];
-        if (v->bfraction == 0) {
-            v->s.pict_type = AV_PICTURE_TYPE_BI; /* XXX: should not happen here */
+    if (v->fcm == PROGRESSIVE) {
+        if (v->finterpflag)
+            v->interpfrm = get_bits1(gb);
+        if (v->s.pict_type == AV_PICTURE_TYPE_B) {
+            v->bfraction_lut_index = get_vlc2(gb, ff_vc1_bfraction_vlc.table, VC1_BFRACTION_VLC_BITS, 1);
+            v->bfraction           = ff_vc1_bfraction_lut[v->bfraction_lut_index];
+            if (v->bfraction == 0) {
+                v->s.pict_type = AV_PICTURE_TYPE_BI; /* XXX: should not happen here */
+            }
         }
     }