let vinfo = frm.get_buffer().get_video_info().unwrap();
if vinfo.get_format().is_paletted() {
write_palppm(pfx, streamno, pts, frm);
let vinfo = frm.get_buffer().get_video_info().unwrap();
if vinfo.get_format().is_paletted() {
write_palppm(pfx, streamno, pts, frm);