IVTV_F_B_NEED_BUF_SWAP
if ((buf->b_flags & IVTV_F_B_NEED_BUF_SWAP) == 0)
buf->b_flags &= ~IVTV_F_B_NEED_BUF_SWAP;
buf->b_flags |= IVTV_F_B_NEED_BUF_SWAP;