libavcodec/mpeg4videodec.c:1154: error: Uninitialized Value
  The value read from dc_pred_dir was never initialized.

libavcodec/mpeg4videodec.c:1154:9: 
1152.         }
1153. 
1154.         ff_mpeg4_pred_ac(s, block, n, dc_pred_dir);
              ^
1155.         if (s->ac_pred)
1156.             i = 63;  // FIXME not optimal
