AV_WL32(st->codec->extradata, AV_RL32(buf + 16));
st->codec->width = AV_RL32(buf + 36);
st->codec->height = AV_RL32(buf + 40);
AV_WL32(st->codec->extradata, AV_RL32(buf + 16));
st->codec->width = AV_RL32(buf + 36);
st->codec->height = AV_RL32(buf + 40);