msmpeg4v2: initialize mb_type array

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/msmpeg4.c

@@ -409,6 +409,7 @@ static int msmpeg4v2_decode_motion(MpegEncContext * s, int pred, int f_code)
 static int msmpeg4v12_decode_mb(MpegEncContext *s, DCTELEM block[6][64])
 {
     int cbp, code, i;
+    uint32_t * const mb_type_ptr = &s->current_picture.f.mb_type[s->mb_x + s->mb_y*s->mb_stride];
 
     if (s->pict_type == AV_PICTURE_TYPE_P) {
         if (s->use_skip_mb_code) {
@@ -422,6 +423,7 @@ static int msmpeg4v12_decode_mb(MpegEncContext *s, DCTELEM block[6][64])
                 s->mv[0][0][0] = 0;
                 s->mv[0][0][1] = 0;
                 s->mb_skipped = 1;
+                *mb_type_ptr = MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
                 return 0;
             }
         }
@@ -470,6 +472,7 @@ static int msmpeg4v12_decode_mb(MpegEncContext *s, DCTELEM block[6][64])
         s->mv_type = MV_TYPE_16X16;
         s->mv[0][0][0] = mx;
         s->mv[0][0][1] = my;
+        *mb_type_ptr = MB_TYPE_L0 | MB_TYPE_16x16;
     } else {
         if(s->msmpeg4_version==2){
             s->ac_pred = get_bits1(&s->gb);
@@ -479,6 +482,7 @@ static int msmpeg4v12_decode_mb(MpegEncContext *s, DCTELEM block[6][64])
             cbp|= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1)<<2; //FIXME check errors
             if(s->pict_type==AV_PICTURE_TYPE_P) cbp^=0x3C;
         }
+        *mb_type_ptr = MB_TYPE_INTRA;
     }
 
     s->dsp.clear_blocks(s->block[0]);