libavcodec/ps.c:954: error: Uninitialized Value
  The value read from h12i_step was never initialized.

libavcodec/ps.c:954:21: 
952.                 if (!PS_BASELINE && ps->enable_ipdopd) {
953.                     h11i += h11i_step;
954.                     h12i += h12i_step;
                         ^
955.                     h21i += h21i_step;
956.                     h22i += h22i_step;
