AV_WB32(st->codecpar->extradata, len);
AV_WL32(st->codecpar->extradata+4, tag);
AV_WB32(st->codecpar->extradata+8, st->codecpar->width);
AV_WB32(st->codecpar->extradata, len);
AV_WL32(st->codecpar->extradata+4, tag);
AV_WB32(st->codecpar->extradata+8, st->codecpar->width);