let (tb_num, tb_den) = str.get_timebase();
let ts = NATimeInfo::new(Some(self.apos), None, None, tb_num, tb_den);
let apkt = self.src.read_packet(str, ts, false, asize)?;
let (tb_num, tb_den) = str.get_timebase();
let ts = NATimeInfo::new(Some(self.apos), None, None, tb_num, tb_den);
let apkt = self.src.read_packet(str, ts, false, asize)?;