diff --git a/src/modules/module-rtp/audio.c b/src/modules/module-rtp/audio.c index 045604b72..8c5517e46 100644 --- a/src/modules/module-rtp/audio.c +++ b/src/modules/module-rtp/audio.c @@ -22,6 +22,15 @@ static void ringbuffer_clear(struct spa_ringbuffer *rbuf SPA_UNUSED, memset(iov[1].iov_base, 0, iov[1].iov_len); } +static inline uint64_t scale_u64(uint64_t val, uint32_t num, uint32_t denom) +{ +#if 0 + return ((__uint128_t)val * num) / denom; +#else + return (uint64_t)((double)val / denom * num); +#endif +} + static void rtp_audio_process_playback(void *data) { struct impl *impl = data; @@ -107,9 +116,15 @@ static void rtp_audio_process_playback(void *data) * quantity tracks how many samples are actually available. */ if (impl->io_position) { - /* Shift clock position by stream delay to compensate - * for processing and output delay. */ - timestamp = impl->io_position->clock.position + device_delay; + uint32_t clock_rate = impl->io_position->clock.rate.denom; + + /* Translate the clock position to an RTP timestamp and + * shift it to compensate for device delay and ASRC delay. + * The device delay is scaled along with the clock position, + * since both are expressed in clock sample units, while + * pwt.buffered is expressed in stream time. */ + timestamp = scale_u64(impl->io_position->clock.position + device_delay, + impl->rate, clock_rate) + pwt.buffered; spa_ringbuffer_read_update(&impl->ring, timestamp); avail = spa_ringbuffer_get_read_index(&impl->ring, &read_index); } else {