[FFmpeg-cvslog] vc1dec: Set opposite to the correct value for 1REF field pictures

[Mashiat Sarker Shakkhar]

ffmpeg | branch: master | Mashiat Sarker Shakkhar <mashiat.sarker at gmail.com> | Tue Oct  9 19:38:18 2012 +0000| [eb657ecefdeb8b2ed9bfb55d3c2c9e0f568486bf] | committer: Derek Buitenhuis

vc1dec: Set opposite to the correct value for 1REF field pictures

Signed-off-by: Derek Buitenhuis <derek.buitenhuis at gmail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=eb657ecefdeb8b2ed9bfb55d3c2c9e0f568486bf
---

 libavcodec/vc1dec.c |   14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/libavcodec/vc1dec.c b/libavcodec/vc1dec.c
index 491e200..40164cc 100644
--- a/libavcodec/vc1dec.c
+++ b/libavcodec/vc1dec.c
@@ -1458,10 +1458,16 @@ static inline void vc1_pred_mv(VC1Context *v, int n, int dmv_x, int dmv_y,
     }
 
     if (v->field_mode) {
-        if (num_samefield <= num_oppfield)
-            opposite = 1 - pred_flag;
-        else
-            opposite = pred_flag;
+        if (!v->numref)
+            // REFFIELD determines if the last field or the second-last field is
+            // to be used as reference
+            opposite = 1 - v->reffield;
+        else {
+            if (num_samefield <= num_oppfield)
+                opposite = 1 - pred_flag;
+            else
+                opposite = pred_flag;
+        }
     } else
         opposite = 0;
     if (opposite) {