libavcodec/h264_direct.c:323: error: Uninitialized Value
  The value read from mv[_] was never initialized.

libavcodec/h264_direct.c:323:21: 
321.                     a= mv[0];
322.                 if(ref[1] > 0)
323.                     b= mv[1];
                         ^
324.             }else{
325.                 a= mv[0];
