segfault fix

Originally committed as revision 4491 to svn://svn.ffmpeg.org/ffmpeg/trunk
20 years ago · 804b0dac58
parent d2f820a5cd
commit 804b0dac58
1 changed files with 5 additions and 2 deletions
--- a/libavcodec/wmv2.c
+++ b/libavcodec/wmv2.c
@ -513,9 +513,12 @@ static int16_t *wmv2_pred_motion(Wmv2Context *w, int *px, int *py){
    B = s->current_picture.motion_val[0][xy - wrap];
    C = s->current_picture.motion_val[0][xy + 2 - wrap];
    
-    diff= FFMAX(ABS(A[0] - B[0]), ABS(A[1] - B[1]));
+    if(s->mb_x && !s->first_slice_line && !s->mspel && w->top_left_mv_flag)
+        diff= FFMAX(ABS(A[0] - B[0]), ABS(A[1] - B[1]));
+    else 
+        diff=0;
    
-    if(s->mb_x && !s->first_slice_line && !s->mspel && w->top_left_mv_flag && diff >= 8)
+    if(diff >= 8)
        type= get_bits1(&s->gb);
    else
        type= 2;