/* Called from main context */
static void adjust_rates(struct userdata *u) {
size_t buffer, fs;
uint32_t old_rate, base_rate, new_rate;
pa_usec_t buffer_latency;
pa_assert(u);
pa_assert_ctl_context();
pa_asyncmsgq_send(u->source_output->source->asyncmsgq, PA_MSGOBJECT(u->source_output), SOURCE_OUTPUT_MESSAGE_LATENCY_SNAPSHOT, NULL, 0, NULL);
pa_asyncmsgq_send(u->sink_input->sink->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_LATENCY_SNAPSHOT, NULL, 0, NULL);
buffer =
u->latency_snapshot.sink_input_buffer +
u->latency_snapshot.source_output_buffer;
if (u->latency_snapshot.recv_counter <= u->latency_snapshot.send_counter)
buffer += (size_t) (u->latency_snapshot.send_counter - u->latency_snapshot.recv_counter);
else
buffer += PA_CLIP_SUB(buffer, (size_t) (u->latency_snapshot.recv_counter - u->latency_snapshot.send_counter));
buffer_latency = pa_bytes_to_usec(buffer, &u->sink_input->sample_spec);
pa_log_debug("Loopback overall latency is %0.2f ms + %0.2f ms + %0.2f ms = %0.2f ms",
(double) u->latency_snapshot.sink_latency / PA_USEC_PER_MSEC,
(double) buffer_latency / PA_USEC_PER_MSEC,
(double) u->latency_snapshot.source_latency / PA_USEC_PER_MSEC,
((double) u->latency_snapshot.sink_latency + buffer_latency + u->latency_snapshot.source_latency) / PA_USEC_PER_MSEC);
pa_log_debug("Should buffer %zu bytes, buffered at minimum %zu bytes",
u->latency_snapshot.max_request*2,
u->latency_snapshot.min_memblockq_length);
fs = pa_frame_size(&u->sink_input->sample_spec);
old_rate = u->sink_input->sample_spec.rate;
base_rate = u->source_output->sample_spec.rate;
if (u->latency_snapshot.min_memblockq_length < u->latency_snapshot.max_request*2)
new_rate = base_rate - (((u->latency_snapshot.max_request*2 - u->latency_snapshot.min_memblockq_length) / fs) *PA_USEC_PER_SEC)/u->adjust_time;
else
new_rate = base_rate + (((u->latency_snapshot.min_memblockq_length - u->latency_snapshot.max_request*2) / fs) *PA_USEC_PER_SEC)/u->adjust_time;
if (new_rate < (uint32_t) (base_rate*0.8) || new_rate > (uint32_t) (base_rate*1.25)) {
pa_log_warn("Sample rates too different, not adjusting (%u vs. %u).", base_rate, new_rate);
new_rate = base_rate;
} else {
if (base_rate < new_rate + 20 && new_rate < base_rate + 20)
new_rate = base_rate;
/* Do the adjustment in small steps; 2‰ can be considered inaudible */
if (new_rate < (uint32_t) (old_rate*0.998) || new_rate > (uint32_t) (old_rate*1.002)) {
pa_log_info("New rate of %u Hz not within 2‰ of %u Hz, forcing smaller adjustment", new_rate, old_rate);
new_rate = PA_CLAMP(new_rate, (uint32_t) (old_rate*0.998), (uint32_t) (old_rate*1.002));
}
}
pa_sink_input_set_rate(u->sink_input, new_rate);
pa_log_debug("[%s] Updated sampling rate to %lu Hz.", u->sink_input->sink->name, (unsigned long) new_rate);
pa_core_rttime_restart(u->core, u->time_event, pa_rtclock_now() + u->adjust_time);
}
/* Called from main context */
static void adjust_rates(struct userdata *u) {
size_t buffer;
uint32_t old_rate, base_rate, new_rate;
int32_t latency_difference;
pa_usec_t current_buffer_latency, snapshot_delay, current_source_sink_latency, current_latency, latency_at_optimum_rate;
pa_usec_t final_latency;
pa_assert(u);
pa_assert_ctl_context();
/* Rates and latencies*/
old_rate = u->sink_input->sample_spec.rate;
base_rate = u->source_output->sample_spec.rate;
buffer = u->latency_snapshot.sink_input_buffer;
if (u->latency_snapshot.recv_counter <= u->latency_snapshot.send_counter)
buffer += (size_t) (u->latency_snapshot.send_counter - u->latency_snapshot.recv_counter);
else
buffer = PA_CLIP_SUB(buffer, (size_t) (u->latency_snapshot.recv_counter - u->latency_snapshot.send_counter));
current_buffer_latency = pa_bytes_to_usec(buffer, &u->sink_input->sample_spec);
snapshot_delay = u->latency_snapshot.source_timestamp - u->latency_snapshot.sink_timestamp;
current_source_sink_latency = u->latency_snapshot.sink_latency + u->latency_snapshot.source_latency - snapshot_delay;
/* Current latency */
current_latency = current_source_sink_latency + current_buffer_latency;
/* Latency at base rate */
latency_at_optimum_rate = current_source_sink_latency + current_buffer_latency * old_rate / base_rate;
final_latency = u->latency;
latency_difference = (int32_t)((int64_t)latency_at_optimum_rate - final_latency);
pa_log_debug("Loopback overall latency is %0.2f ms + %0.2f ms + %0.2f ms = %0.2f ms",
(double) u->latency_snapshot.sink_latency / PA_USEC_PER_MSEC,
(double) current_buffer_latency / PA_USEC_PER_MSEC,
(double) u->latency_snapshot.source_latency / PA_USEC_PER_MSEC,
(double) current_latency / PA_USEC_PER_MSEC);
pa_log_debug("Loopback latency at base rate is %0.2f ms", (double)latency_at_optimum_rate / PA_USEC_PER_MSEC);
/* Calculate new rate */
new_rate = rate_controller(base_rate, u->adjust_time, latency_difference);
/* Set rate */
pa_sink_input_set_rate(u->sink_input, new_rate);
pa_log_debug("[%s] Updated sampling rate to %lu Hz.", u->sink_input->sink->name, (unsigned long) new_rate);
}
/* Called from output thread context */
static void source_output_state_change_cb(pa_source_output *o, pa_source_output_state_t state) {
struct userdata *u;
pa_source_output_assert_ref(o);
pa_source_output_assert_io_context(o);
pa_assert_se(u = o->userdata);
if (PA_SOURCE_OUTPUT_IS_LINKED(state) && o->thread_info.state == PA_SOURCE_OUTPUT_INIT) {
u->skip = pa_usec_to_bytes(PA_CLIP_SUB(pa_source_get_latency_within_thread(o->source),
u->latency),
&o->sample_spec);
pa_log_info("Skipping %lu bytes", (unsigned long) u->skip);
}
}
/* Called from main context */
static void adjust_rates(struct userdata *u) {
size_t buffer, fs;
uint32_t old_rate, base_rate, new_rate;
pa_usec_t buffer_latency;
pa_assert(u);
pa_assert_ctl_context();
pa_asyncmsgq_send(u->source_output->source->asyncmsgq, PA_MSGOBJECT(u->source_output), SOURCE_OUTPUT_MESSAGE_LATENCY_SNAPSHOT, NULL, 0, NULL);
pa_asyncmsgq_send(u->sink_input->sink->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_LATENCY_SNAPSHOT, NULL, 0, NULL);
buffer =
u->latency_snapshot.sink_input_buffer +
u->latency_snapshot.source_output_buffer;
if (u->latency_snapshot.recv_counter <= u->latency_snapshot.send_counter)
buffer += (size_t) (u->latency_snapshot.send_counter - u->latency_snapshot.recv_counter);
else
buffer += PA_CLIP_SUB(buffer, (size_t) (u->latency_snapshot.recv_counter - u->latency_snapshot.send_counter));
buffer_latency = pa_bytes_to_usec(buffer, &u->sink_input->sample_spec);
pa_log_info("Loopback overall latency is %0.2f ms + %0.2f ms + %0.2f ms = %0.2f ms",
(double) u->latency_snapshot.sink_latency / PA_USEC_PER_MSEC,
(double) buffer_latency / PA_USEC_PER_MSEC,
(double) u->latency_snapshot.source_latency / PA_USEC_PER_MSEC,
((double) u->latency_snapshot.sink_latency + buffer_latency + u->latency_snapshot.source_latency) / PA_USEC_PER_MSEC);
pa_log_info("Should buffer %zu bytes, buffered at minimum %zu bytes",
u->latency_snapshot.max_request*2,
u->latency_snapshot.min_memblockq_length);
fs = pa_frame_size(&u->sink_input->sample_spec);
old_rate = u->sink_input->sample_spec.rate;
base_rate = u->source_output->sample_spec.rate;
if (u->latency_snapshot.min_memblockq_length < u->latency_snapshot.max_request*2)
new_rate = base_rate - (((u->latency_snapshot.max_request*2 - u->latency_snapshot.min_memblockq_length) / fs) *PA_USEC_PER_SEC)/u->adjust_time;
else
new_rate = base_rate + (((u->latency_snapshot.min_memblockq_length - u->latency_snapshot.max_request*2) / fs) *PA_USEC_PER_SEC)/u->adjust_time;
pa_log_info("Old rate %lu Hz, new rate %lu Hz", (unsigned long) old_rate, (unsigned long) new_rate);
pa_sink_input_set_rate(u->sink_input, new_rate);
pa_core_rttime_restart(u->core, u->time_event, pa_rtclock_now() + u->adjust_time);
}