V4L2_PIX_FMT_FLAG_PREMUL_ALPHA
flags & V4L2_PIX_FMT_FLAG_PREMUL_ALPHA ?
& V4L2_PIX_FMT_FLAG_PREMUL_ALPHA;
rpf->format.flags = cfg->premult ? V4L2_PIX_FMT_FLAG_PREMUL_ALPHA : 0;
& V4L2_PIX_FMT_FLAG_PREMUL_ALPHA;