This is the final version of my patch for module-loopback. It is on top of the
patch I sent about an hour ago and contains a lot more changes than the previous
versions:
- Honor specified latency if possible, if not adjust to the lowest possible value
- Smooth switching from fixed latency to dynamic latency source or sink and vice versa
- good rate and latency stability, no rate oscillation
- adjusts latency as good as your setup allows
- fast regulation of latency offsets, adjusts 100 ms offset within 22 seconds (adjust
time=1) to 60 seconds (adjust_time=10)
- usable latency range 4 - 30000 ms
- Avoid rewinds and "cannot peek into queue" messages during startup and switching
- works with rates between 200 and 190000 Hz
- maximum latency offset after source/sink switch or at startup around is 200 ms
I also introduced a new parameter, buffer_latency_msec which can be used together
with latency_msec. If buffer_latency_msec is specified, the resulting latency
will be latency_msec + buffer_latency_msec. Latency_msec then refers only to
the source/sink latency while buffer_latency_msec specifies the buffer part.
This can be used to save a lot of CPU at low latencies, running 10 ms latency
with latency_msec=6 buffer_latency_msec=4 gives 8% CPU on my system compared to
12% when I only specify latency_msec=10.
Additionally you can go beyond the safe-guard limits that are built in, you can
access the range 1 - 3 ms or lower the buffer latency for fixed latency devices.
Some of my USB devices run fine at a buffer latency of fragment size + 4 ms
instead of the dfault fragment size + 20 ms.
I tested it all with Intel HDA, USB and bluetooth sound devices. I would like to
see some test results from other people.
---
src/modules/module-loopback.c | 539 +++++++++++++++++++++++++++++++-----------
1 file changed, 397 insertions(+), 142 deletions(-)
diff --git a/src/modules/module-loopback.c b/src/modules/module-loopback.c
index 7e2b92a..8def03e 100644
--- a/src/modules/module-loopback.c
+++ b/src/modules/module-loopback.c
@@ -47,6 +47,7 @@ PA_MODULE_USAGE(
"sink=<sink to connect to> "
"adjust_time=<how often to readjust rates in s> "
"latency_msec=<latency in ms> "
+ "buffer_latency_msec=<buffer latency in ms> "
"format=<sample format> "
"rate=<sample rate> "
"channels=<number of channels> "
@@ -59,7 +60,9 @@ PA_MODULE_USAGE(
#define DEFAULT_LATENCY_MSEC 200
-#define MEMBLOCKQ_MAXLENGTH (1024*1024*16)
+#define MEMBLOCKQ_MAXLENGTH (1024*1024*32)
+
+#define DEFAULT_BUFFER_MARGIN_MSEC 20
#define DEFAULT_ADJUST_TIME_USEC (10*PA_USEC_PER_SEC)
@@ -80,12 +83,26 @@ struct userdata {
int64_t recv_counter;
int64_t send_counter;
+ uint32_t sink_adjust_counter;
+ uint32_t source_adjust_counter;
+ uint32_t underruns;
+ uint32_t no_peeks;
- size_t skip;
pa_usec_t latency;
+ pa_usec_t buffer_latency;
+ pa_usec_t initial_buffer_latency;
+ pa_usec_t configured_sink_latency;
+ pa_usec_t configured_source_latency;
+
+ pa_usec_t source_latency_sum;
+ pa_usec_t sink_latency_sum;
+ pa_usec_t next_latency;
+ double latency_error;
bool in_pop;
- size_t min_memblockq_length;
+ bool pop_called;
+ bool source_sink_changed;
+ bool buffer_latency_set;
struct {
int64_t send_counter;
@@ -95,9 +112,6 @@ struct userdata {
int64_t recv_counter;
size_t sink_input_buffer;
pa_usec_t sink_latency;
-
- size_t min_memblockq_length;
- size_t max_request;
} latency_snapshot;
};
@@ -106,6 +120,7 @@ static const char* const valid_modargs[] = {
"sink",
"adjust_time",
"latency_msec",
+ "buffer_latency_msec",
"format",
"rate",
"channels",
@@ -121,8 +136,7 @@ static const char* const valid_modargs[] = {
enum {
SINK_INPUT_MESSAGE_POST = PA_SINK_INPUT_MESSAGE_MAX,
SINK_INPUT_MESSAGE_REWIND,
- SINK_INPUT_MESSAGE_LATENCY_SNAPSHOT,
- SINK_INPUT_MESSAGE_MAX_REQUEST_CHANGED
+ SINK_INPUT_MESSAGE_LATENCY_SNAPSHOT
};
enum {
@@ -168,84 +182,134 @@ static void teardown(struct userdata *u) {
}
/* 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;
+static void adjust_rates(struct userdata *u, pa_usec_t snapshot_delay) {
+ size_t buffer;
+ uint32_t old_rate, base_rate, new_rate, hours, cut_off_frequency;
+ pa_usec_t final_latency, source_sink_latency, current_buffer_latency, current_latency, corrected_latency;
+ double min_cycles;
+ int32_t latency_difference;
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);
+ /* Runtime and counters since last change of source or sink */
+ hours = PA_MIN(u->sink_adjust_counter, u->source_adjust_counter) * u->adjust_time / PA_USEC_PER_SEC / 3600;
+ u->sink_adjust_counter +=1;
+ u->source_adjust_counter +=1;
+
+ /* Latency sums */
+ u->source_latency_sum += u->latency_snapshot.source_latency;
+ u->sink_latency_sum += u->latency_snapshot.sink_latency;
+
+ /* If we are seeing underruns or cannot peek into the queue during pop then the latency is too small */
+ if (u->underruns > 2 || u->no_peeks > 30) {
+ u->buffer_latency += 5 * PA_USEC_PER_MSEC;
+ pa_log_warn("Too many underruns, increasing buffer latency to %0.2f ms", (double) u->buffer_latency / PA_USEC_PER_MSEC);
+ u->underruns = 0;
+ u->no_peeks = 0;
+ }
- buffer =
- u->latency_snapshot.sink_input_buffer +
- u->latency_snapshot.source_output_buffer;
+ /* Allow one underrun and 15 no peek messages per hour */
+ if (PA_MIN(u->sink_adjust_counter, u->source_adjust_counter) * u->adjust_time / PA_USEC_PER_SEC / 3600 > hours) {
+ pa_log_info("Underrun counters: %u, %u", u->underruns, u->no_peeks);
+ u->underruns = PA_CLIP_SUB(u->underruns, 1u);
+ u->no_peeks = PA_CLIP_SUB(u->no_peeks, 15u);
+ }
+
+ /* 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 + 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 = 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);
- buffer_latency = pa_bytes_to_usec(buffer, &u->sink_input->sample_spec);
+ current_latency = u->latency_snapshot.sink_latency + current_buffer_latency + u->latency_snapshot.source_latency - snapshot_delay;
- pa_log_debug("Loopback overall latency is %0.2f ms + %0.2f ms + %0.2f ms = %0.2f ms",
+ source_sink_latency = u->sink_latency_sum / u->sink_adjust_counter +
+ u->source_latency_sum / u->source_adjust_counter;
+ final_latency = u->latency;
+ if (u->buffer_latency_set)
+ final_latency += u->initial_buffer_latency;
+ final_latency = PA_MAX(final_latency, source_sink_latency + u->buffer_latency);
+
+ pa_log_debug("Loopback overall latency is %0.2f ms + %0.2f ms + %0.2f ms = %0.2f ms, latency difference: %0.2f ms, rate difference: %i Hz",
(double) u->latency_snapshot.sink_latency / PA_USEC_PER_MSEC,
- (double) buffer_latency / PA_USEC_PER_MSEC,
+ (double) current_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; 2â?° 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 2â?° 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));
- }
+ (double) current_latency / PA_USEC_PER_MSEC,
+ (double) (int32_t)(current_latency - final_latency) / PA_USEC_PER_MSEC,
+ (int32_t)(old_rate - base_rate));
+
+ /* Low pass filtered difference between expectation value and observed latency */
+ if (!u->source_sink_changed)
+ u->latency_error = (4 * u->latency_error + (double)abs((int32_t)(current_latency - u->next_latency)) / final_latency) / 5;
+ else
+ u->source_sink_changed = false;
+
+ /* Latency and latency difference at base rate */
+ corrected_latency = u->latency_snapshot.source_latency + (u->latency_snapshot.sink_latency + current_buffer_latency) * old_rate / base_rate - snapshot_delay;
+ latency_difference = (int32_t)(corrected_latency - final_latency);
+
+ /* Minimum number of adjust times + 1 needed to adjust at 0.75% deviation from base rate */
+ min_cycles = (double)abs(latency_difference) / u->adjust_time / 0.0075 + 1;
+
+ /* Rate calculation, maximum deviation from base rate will be less than 0.75% due to min_cycles */
+ new_rate = base_rate * (1.0 + latency_difference / min_cycles / u->adjust_time) + 0.5;
+
+ /* Adjust as good as physics allows (with some safety margin) */
+ if (abs(latency_difference) <= 2.5 * u->latency_error * final_latency + u->adjust_time / 2 / base_rate + 100)
+ new_rate = base_rate;
+
+ /* Do the adjustment in small steps; 2â?° of base rate can be considered inaudible, use 1 Hz below 500 Hz base rate */
+ cut_off_frequency = PA_MAX(1, 0.002 * base_rate);
+ if (new_rate < old_rate - cut_off_frequency || new_rate > old_rate + cut_off_frequency) {
+ pa_log_info("New rate of %u Hz not within 2â?° of %u Hz, forcing smaller adjustment", new_rate, old_rate);
+ new_rate = PA_CLAMP(new_rate, old_rate - cut_off_frequency, old_rate + cut_off_frequency);
}
+ /* Predictor */
+ u->next_latency = (corrected_latency * base_rate + (int32_t)(base_rate - new_rate) * (int64_t)u->adjust_time) / new_rate;
+
+ /* 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);
-
- pa_core_rttime_restart(u->core, u->time_event, pa_rtclock_now() + u->adjust_time);
}
/* Called from main context */
static void time_callback(pa_mainloop_api *a, pa_time_event *e, const struct timeval *t, void *userdata) {
struct userdata *u = userdata;
+ pa_usec_t timestamp;
pa_assert(u);
pa_assert(a);
pa_assert(u->time_event == e);
- adjust_rates(u);
+ /* Restart timer right away */
+ pa_core_rttime_restart(u->core, u->time_event, pa_rtclock_now() + u->adjust_time);
+
+ /* Get sink and source latency snapshot. The resulting latency must be corrected by the delay between sink and
+ * source snapshot which can somtimes be quite large (>>10 ms) */
+ pa_asyncmsgq_send(u->sink_input->sink->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_LATENCY_SNAPSHOT, NULL, 0, NULL);
+ timestamp = pa_rtclock_now();
+ pa_asyncmsgq_send(u->source_output->source->asyncmsgq, PA_MSGOBJECT(u->source_output), SOURCE_OUTPUT_MESSAGE_LATENCY_SNAPSHOT, NULL, 0, NULL);
+
+ adjust_rates(u, pa_rtclock_now() - timestamp);
}
-/* Called from main context */
+/* Called from main context
+ * When source or sink changes, give it a third of a second to settle down, then call adjust_rates for the first time */
static void enable_adjust_timer(struct userdata *u, bool enable) {
if (enable) {
- if (u->time_event || u->adjust_time <= 0)
+ if (!u->adjust_time)
return;
+ if (u->time_event)
+ u->core->mainloop->time_free(u->time_event);
- u->time_event = pa_core_rttime_new(u->module->core, pa_rtclock_now() + u->adjust_time, time_callback, u);
+ u->time_event = pa_core_rttime_new(u->module->core, pa_rtclock_now() + 333 * PA_USEC_PER_MSEC, time_callback, u);
} else {
if (!u->time_event)
return;
@@ -263,29 +327,62 @@ static void update_adjust_timer(struct userdata *u) {
enable_adjust_timer(u, true);
}
+static pa_usec_t get_requested_latency(struct userdata *u) {
+ pa_usec_t requested_latency;
+
+ requested_latency = u->latency;
+ if(u->buffer_latency_set)
+ requested_latency += u->buffer_latency;
+ return PA_MAX(u->configured_sink_latency + u->buffer_latency, requested_latency);
+}
+
+/* Called from all contexts */
+static void memblockq_adjust(struct userdata *u, int32_t offset, bool allow_push) {
+ size_t memblock_bytes, requested_buffer_bytes;
+ pa_usec_t requested_buffer_latency;
+ size_t buffer_offset;
+ pa_memchunk silence;
+
+ requested_buffer_latency = get_requested_latency(u);
+ if (offset > 0)
+ requested_buffer_latency = PA_CLIP_SUB(requested_buffer_latency, (pa_usec_t)offset);
+ else
+ requested_buffer_latency = requested_buffer_latency - offset;
+
+ requested_buffer_bytes = pa_usec_to_bytes(requested_buffer_latency, &u->sink_input->sample_spec);
+ memblock_bytes = pa_memblockq_get_length(u->memblockq);
+
+ /* Drop audio from queue */
+ if ((int32_t)(memblock_bytes - requested_buffer_bytes) > 0) {
+ buffer_offset = memblock_bytes - requested_buffer_bytes;
+ pa_log_info("Dropping %zd bytes from queue", buffer_offset);
+ pa_memblockq_drop(u->memblockq, buffer_offset);
+ }
+ /* Add silence to queue, will never happen from IO-thread */
+ else if ((int32_t)(memblock_bytes - requested_buffer_bytes) < 0 && allow_push) {
+ requested_buffer_bytes = requested_buffer_bytes - memblock_bytes;
+ pa_log_info("Adding %zd bytes of silence to queue", requested_buffer_bytes);
+ pa_sink_input_get_silence(u->sink_input, &silence);
+ while (requested_buffer_bytes >= silence.length) {
+ pa_memblockq_push_align(u->memblockq, &silence);
+ requested_buffer_bytes -= silence.length;
+ }
+ if (requested_buffer_bytes > 0) {
+ silence.length = requested_buffer_bytes;
+ pa_memblockq_push_align(u->memblockq, &silence);
+ }
+ pa_memblock_unref(silence.memblock);
+ }
+}
+
/* Called from input thread context */
static void source_output_push_cb(pa_source_output *o, const pa_memchunk *chunk) {
struct userdata *u;
- pa_memchunk copy;
pa_source_output_assert_ref(o);
pa_source_output_assert_io_context(o);
pa_assert_se(u = o->userdata);
- if (u->skip >= chunk->length) {
- u->skip -= chunk->length;
- return;
- }
-
- if (u->skip > 0) {
- copy = *chunk;
- copy.index += u->skip;
- copy.length -= u->skip;
- u->skip = 0;
-
- chunk = ©
- }
-
pa_asyncmsgq_post(u->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_POST, NULL, 0, chunk, NULL);
u->send_counter += (int64_t) chunk->length;
}
@@ -324,6 +421,36 @@ static int source_output_process_msg_cb(pa_msgobject *obj, int code, void *data,
return pa_source_output_process_msg(obj, code, data, offset, chunk);
}
+static void set_source_output_latency(struct userdata *u, pa_source *source) {
+ pa_usec_t min_latency, max_latency, buffer_msec, latency;
+
+ /* Set lower limit of source latency to 2.333 ms, if buffer
+ * latency is specified, use latency_msec as source latency */
+ latency = PA_MAX(u->latency / 3, 2.333 * PA_USEC_PER_MSEC);
+ if (u->buffer_latency_set)
+ latency = u->latency;
+
+ if(source->flags & PA_SOURCE_DYNAMIC_LATENCY) {
+ pa_source_get_latency_range(source, &min_latency, &max_latency);
+ if (min_latency > latency && !u->buffer_latency_set) {
+ u->buffer_latency = PA_MAX(u->buffer_latency, (pa_usec_t)(min_latency * 0.75));
+ pa_log_warn("Cannot set requested source latency, adjusting buffer to %0.2f ms", (double)u->buffer_latency / PA_USEC_PER_MSEC);
+ }
+ latency = PA_CLAMP(latency, min_latency, max_latency);
+ }
+ else {
+ latency = pa_source_get_latency(source);
+ if (latency == 0)
+ latency = pa_source_get_fixed_latency(source);
+ buffer_msec = u->core->default_fragment_size_msec + DEFAULT_BUFFER_MARGIN_MSEC;
+ if (!u->buffer_latency_set && u->buffer_latency < buffer_msec * PA_USEC_PER_MSEC) {
+ pa_log_warn("Fixed latency device, setting buffer latency to %zd.00 ms", buffer_msec);
+ u->buffer_latency = buffer_msec * PA_USEC_PER_MSEC;
+ }
+ }
+ u->configured_source_latency = pa_source_output_set_requested_latency(u->source_output, latency);
+}
+
/* Called from output thread context */
static void source_output_attach_cb(pa_source_output *o) {
struct userdata *u;
@@ -350,24 +477,12 @@ static void source_output_detach_cb(pa_source_output *o) {
pa_rtpoll_item_free(u->rtpoll_item_write);
u->rtpoll_item_write = NULL;
}
-}
-
-/* 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);
- }
+ u->source_sink_changed = true;
+ u->source_latency_sum = 0;
+ u->source_adjust_counter = 0;
+ u->underruns = 0;
+ u->no_peeks = 0;
+ u->buffer_latency = u->initial_buffer_latency;
}
/* Called from main thread */
@@ -393,7 +508,12 @@ static bool source_output_may_move_to_cb(pa_source_output *o, pa_source *dest) {
if (!u->sink_input || !u->sink_input->sink)
return true;
- return dest != u->sink_input->sink->monitor_source;
+ /* We may still be adjusting, so reset rate to default before moving the source */
+ if (dest != u->sink_input->sink->monitor_source) {
+ pa_sink_input_set_rate(u->sink_input, u->source_output->sample_spec.rate);
+ return true;
+ }
+ return false;
}
/* Called from main thread */
@@ -401,6 +521,7 @@ static void source_output_moving_cb(pa_source_output *o, pa_source *dest) {
pa_proplist *p;
const char *n;
struct userdata *u;
+ pa_usec_t sink_latency;
if (!dest)
return;
@@ -418,6 +539,26 @@ static void source_output_moving_cb(pa_source_output *o, pa_source *dest) {
pa_sink_input_update_proplist(u->sink_input, PA_UPDATE_REPLACE, p);
pa_proplist_free(p);
+ /* Set latency and calculate necessary buffer length */
+ set_source_output_latency(u, dest);
+ if (!u->buffer_latency_set) {
+ if (u->sink_input->sink->flags & PA_SINK_DYNAMIC_LATENCY)
+ u->buffer_latency = PA_MAX(u->buffer_latency, (pa_usec_t)(u->configured_sink_latency * 0.75));
+ else
+ u->buffer_latency = PA_MAX(u->buffer_latency, (u->core->default_fragment_size_msec + DEFAULT_BUFFER_MARGIN_MSEC) * PA_USEC_PER_MSEC);
+ }
+
+ pa_sink_input_get_latency(u->sink_input, &sink_latency);
+ if (u->send_counter > u->recv_counter)
+ sink_latency += pa_bytes_to_usec(u->send_counter - u->recv_counter, &u->sink_input->sample_spec);
+ if (dest->flags & PA_SOURCE_DYNAMIC_LATENCY)
+ sink_latency += pa_source_get_latency(dest);
+ else
+ sink_latency = PA_CLIP_SUB(sink_latency, pa_source_get_latency(dest));
+ memblockq_adjust(u, sink_latency, true);
+
+ u->latency_error = 400.0 / get_requested_latency(u);
+
if (pa_source_get_state(dest) == PA_SOURCE_SUSPENDED)
pa_sink_input_cork(u->sink_input, true);
else
@@ -439,18 +580,29 @@ static void source_output_suspend_cb(pa_source_output *o, bool suspended) {
update_adjust_timer(u);
}
-/* Called from output thread context */
-static void update_min_memblockq_length(struct userdata *u) {
- size_t length;
-
- pa_assert(u);
- pa_sink_input_assert_io_context(u->sink_input);
+/* Called from input thread context */
+static void update_source_requested_latency_cb(pa_source_output *i) {
+ struct userdata *u;
+ pa_usec_t source_latency;
- length = pa_memblockq_get_length(u->memblockq);
+ pa_source_output_assert_ref(i);
+ pa_source_output_assert_io_context(i);
+ pa_assert_se(u = i->userdata);
- if (u->min_memblockq_length == (size_t) -1 ||
- length < u->min_memblockq_length)
- u->min_memblockq_length = length;
+ /* Source latency may have changed */
+ source_latency = pa_source_get_requested_latency_within_thread(u->source_output->source);
+ if (source_latency > u->configured_source_latency) {
+ pa_log_warn("Source latency increased to %0.2f ms", (double)source_latency / PA_USEC_PER_MSEC);
+ u->configured_source_latency = source_latency;
+ if (!u->buffer_latency_set && u->buffer_latency < source_latency * 0.75)
+ u->buffer_latency = source_latency * 0.75;
+ if (!u->source_sink_changed) {
+ u->source_adjust_counter = 0;
+ u->source_latency_sum = 0;
+ u->underruns = 0;
+ u->no_peeks = 0;
+ }
+ }
}
/* Called from output thread context */
@@ -462,21 +614,23 @@ static int sink_input_pop_cb(pa_sink_input *i, size_t nbytes, pa_memchunk *chunk
pa_assert_se(u = i->userdata);
pa_assert(chunk);
+ u->pop_called = true;
u->in_pop = true;
while (pa_asyncmsgq_process_one(u->asyncmsgq) > 0)
;
u->in_pop = false;
if (pa_memblockq_peek(u->memblockq, chunk) < 0) {
- pa_log_info("Could not peek into queue");
+ if (!u->source_sink_changed) {
+ u->no_peeks +=1;
+ pa_log_info("Could not peek into queue");
+ }
return -1;
}
chunk->length = PA_MIN(chunk->length, nbytes);
pa_memblockq_drop(u->memblockq, chunk->length);
- update_min_memblockq_length(u);
-
return 0;
}
@@ -513,12 +667,13 @@ static int sink_input_process_msg_cb(pa_msgobject *obj, int code, void *data, in
pa_sink_input_assert_io_context(u->sink_input);
- if (PA_SINK_IS_OPENED(u->sink_input->sink->thread_info.state))
- pa_memblockq_push_align(u->memblockq, chunk);
- else
- pa_memblockq_flush_write(u->memblockq, true);
+ pa_memblockq_push_align(u->memblockq, chunk);
+ u->recv_counter += (int64_t) chunk->length;
- update_min_memblockq_length(u);
+ if (!PA_SINK_IS_OPENED(u->sink_input->sink->thread_info.state) || !u->pop_called) {
+ memblockq_adjust(u, (int32_t)(-u->configured_sink_latency / 4), false);
+ return 0;
+ }
/* Is this the end of an underrun? Then let's start things
* right-away */
@@ -527,67 +682,76 @@ static int sink_input_process_msg_cb(pa_msgobject *obj, int code, void *data, in
pa_memblockq_is_readable(u->memblockq)) {
pa_log_debug("Requesting rewind due to end of underrun.");
+ if (!u->source_sink_changed)
+ u->underruns +=1;
pa_sink_input_request_rewind(u->sink_input,
(size_t) (u->sink_input->thread_info.underrun_for == (size_t) -1 ? 0 : u->sink_input->thread_info.underrun_for),
false, true, false);
}
- u->recv_counter += (int64_t) chunk->length;
-
return 0;
case SINK_INPUT_MESSAGE_REWIND:
pa_sink_input_assert_io_context(u->sink_input);
- if (PA_SINK_IS_OPENED(u->sink_input->sink->thread_info.state))
+ if (PA_SINK_IS_OPENED(u->sink_input->sink->thread_info.state) && u->pop_called)
pa_memblockq_seek(u->memblockq, -offset, PA_SEEK_RELATIVE, true);
else
- pa_memblockq_flush_write(u->memblockq, true);
+ memblockq_adjust(u, (int32_t)(-u->configured_sink_latency / 4), false);
u->recv_counter -= offset;
- update_min_memblockq_length(u);
-
return 0;
case SINK_INPUT_MESSAGE_LATENCY_SNAPSHOT: {
size_t length;
- update_min_memblockq_length(u);
-
length = pa_memblockq_get_length(u->sink_input->thread_info.render_memblockq);
u->latency_snapshot.recv_counter = u->recv_counter;
- u->latency_snapshot.sink_input_buffer =
- pa_memblockq_get_length(u->memblockq) +
- (u->sink_input->thread_info.resampler ? pa_resampler_request(u->sink_input->thread_info.resampler, length) : length);
+ u->latency_snapshot.sink_input_buffer = pa_memblockq_get_length(u->memblockq) +
+ (u->sink_input->thread_info.resampler ? pa_resampler_request(u->sink_input->thread_info.resampler, length) : length);
u->latency_snapshot.sink_latency = pa_sink_get_latency_within_thread(u->sink_input->sink);
- u->latency_snapshot.max_request = pa_sink_input_get_max_request(u->sink_input);
-
- u->latency_snapshot.min_memblockq_length = u->min_memblockq_length;
- u->min_memblockq_length = (size_t) -1;
-
return 0;
}
- case SINK_INPUT_MESSAGE_MAX_REQUEST_CHANGED: {
- /* This message is sent from the IO thread to the main
- * thread! So don't be confused. All the user cases above
- * are executed in thread context, but this one is not! */
-
- pa_assert_ctl_context();
-
- if (u->time_event)
- adjust_rates(u);
- return 0;
- }
}
return pa_sink_input_process_msg(obj, code, data, offset, chunk);
}
+static void set_sink_input_latency(struct userdata *u, pa_sink *sink) {
+ pa_usec_t min_latency, max_latency, buffer_msec, latency;
+
+ /* Set lower limit of sink latency to 2.333 ms, if buffer
+ * latency is specified, use latency_msec as sink latency */
+ latency = PA_MAX(u->latency / 3, 2.333 * PA_USEC_PER_MSEC);
+ if (u->buffer_latency_set)
+ latency = u->latency;
+
+ if(sink->flags & PA_SINK_DYNAMIC_LATENCY) {
+ pa_sink_get_latency_range(sink, &min_latency, &max_latency);
+ if (min_latency > latency && !u->buffer_latency_set) {
+ u->buffer_latency = PA_MAX(u->buffer_latency, (pa_usec_t)(min_latency * 0.75));
+ pa_log_warn("Cannot set requested sink latency, adjusting buffer to %0.2f ms", (double)u->buffer_latency / PA_USEC_PER_MSEC);
+ }
+ latency = PA_CLAMP(latency, min_latency, max_latency);
+ }
+ else {
+ latency = pa_sink_get_latency(sink);
+ if (latency == 0)
+ latency = pa_sink_get_fixed_latency(sink);
+ buffer_msec = u->core->default_fragment_size_msec + DEFAULT_BUFFER_MARGIN_MSEC;
+ if (!u->buffer_latency_set && u->buffer_latency < buffer_msec * PA_USEC_PER_MSEC) {
+ pa_log_warn("Fixed latency device, setting buffer latency to %zd.00 ms", buffer_msec);
+ u->buffer_latency = buffer_msec * PA_USEC_PER_MSEC;
+ }
+ }
+ u->configured_sink_latency = pa_sink_input_set_requested_latency(u->sink_input, latency);
+}
+
/* Called from output thread context */
static void sink_input_attach_cb(pa_sink_input *i) {
struct userdata *u;
@@ -603,8 +767,6 @@ static void sink_input_attach_cb(pa_sink_input *i) {
pa_memblockq_set_prebuf(u->memblockq, pa_sink_input_get_max_request(i)*2);
pa_memblockq_set_maxrewind(u->memblockq, pa_sink_input_get_max_rewind(i));
-
- u->min_memblockq_length = (size_t) -1;
}
/* Called from output thread context */
@@ -619,6 +781,13 @@ static void sink_input_detach_cb(pa_sink_input *i) {
pa_rtpoll_item_free(u->rtpoll_item_read);
u->rtpoll_item_read = NULL;
}
+ u->source_sink_changed = true;
+ u->pop_called = false;
+ u->sink_latency_sum = 0;
+ u->sink_adjust_counter = 0;
+ u->underruns = 0;
+ u->no_peeks = 0;
+ u->buffer_latency = u->initial_buffer_latency;
}
/* Called from output thread context */
@@ -642,7 +811,6 @@ static void sink_input_update_max_request_cb(pa_sink_input *i, size_t nbytes) {
pa_memblockq_set_prebuf(u->memblockq, nbytes*2);
pa_log_info("Max request changed");
- pa_asyncmsgq_post(pa_thread_mq_get()->outq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_MAX_REQUEST_CHANGED, NULL, 0, NULL, NULL);
}
/* Called from main thread */
@@ -673,6 +841,7 @@ static void sink_input_moving_cb(pa_sink_input *i, pa_sink *dest) {
struct userdata *u;
pa_proplist *p;
const char *n;
+ pa_usec_t source_latency;
if (!dest)
return;
@@ -690,6 +859,22 @@ static void sink_input_moving_cb(pa_sink_input *i, pa_sink *dest) {
pa_source_output_update_proplist(u->source_output, PA_UPDATE_REPLACE, p);
pa_proplist_free(p);
+ /* Set latency and calculate necessary buffer length */
+ set_sink_input_latency(u, dest);
+ if (!u->buffer_latency_set) {
+ if (u->source_output->source->flags & PA_SOURCE_DYNAMIC_LATENCY)
+ u->buffer_latency = PA_MAX(u->buffer_latency, (pa_usec_t)(u->configured_source_latency * 0.75));
+ else
+ u->buffer_latency = PA_MAX(u->buffer_latency, (u->core->default_fragment_size_msec + DEFAULT_BUFFER_MARGIN_MSEC) * PA_USEC_PER_MSEC);
+ }
+
+ pa_source_output_get_latency(u->source_output, &source_latency);
+ if (u->send_counter > u->recv_counter)
+ source_latency += pa_bytes_to_usec(u->send_counter - u->recv_counter, &u->sink_input->sample_spec);
+ memblockq_adjust(u, source_latency, true);
+
+ u->latency_error = 400.0 / get_requested_latency(u);
+
if (pa_sink_get_state(dest) == PA_SINK_SUSPENDED)
pa_source_output_cork(u->source_output, true);
else
@@ -709,7 +894,37 @@ static bool sink_input_may_move_to_cb(pa_sink_input *i, pa_sink *dest) {
if (!u->source_output || !u->source_output->source)
return true;
- return dest != u->source_output->source->monitor_of;
+ /* We may still be adjusting, so reset rate to default before moving the sink */
+ if (dest != u->source_output->source->monitor_of) {
+ pa_sink_input_set_rate(u->sink_input, u->source_output->sample_spec.rate);
+ return true;
+ }
+ return false;
+}
+
+/* Called from output thread context */
+static void update_sink_requested_latency_cb(pa_sink_input *i) {
+ struct userdata *u;
+ pa_usec_t sink_latency;
+
+ pa_sink_input_assert_ref(i);
+ pa_sink_input_assert_io_context(i);
+ pa_assert_se(u = i->userdata);
+
+ /* Sink latency may have changed */
+ sink_latency = pa_sink_get_requested_latency_within_thread(u->sink_input->sink);
+ if (sink_latency > u->configured_sink_latency) {
+ pa_log_warn("Sink latency increased to %0.2f ms", (double)sink_latency / PA_USEC_PER_MSEC);
+ u->configured_sink_latency = sink_latency;
+ if (!u->buffer_latency_set && u->buffer_latency < sink_latency * 0.75)
+ u->buffer_latency = sink_latency * 0.75;
+ if (!u->source_sink_changed) {
+ u->sink_adjust_counter = 0;
+ u->sink_latency_sum = 0;
+ u->underruns = 0;
+ u->no_peeks = 0;
+ }
+ }
}
/* Called from main thread */
@@ -734,12 +949,13 @@ int pa__init(pa_module *m) {
pa_source *source = NULL;
pa_source_output_new_data source_output_data;
bool source_dont_move;
- uint32_t latency_msec;
+ uint32_t latency_msec, buffer_latency_msec;
pa_sample_spec ss;
pa_channel_map map;
bool format_set = false;
bool rate_set = false;
bool channels_set = false;
+ bool buffer_latency_set = false;
pa_memchunk silence;
uint32_t adjust_time_sec;
const char *n;
@@ -799,6 +1015,11 @@ int pa__init(pa_module *m) {
goto fail;
}
+ if (ss.rate < 20 || ss.rate > 190500) {
+ pa_log("Invalid rate specification, valid range is 20 Hz to 190500 Hz");
+ goto fail;
+ }
+
if (pa_modargs_get_value(ma, "format", NULL))
format_set = true;
@@ -808,8 +1029,18 @@ int pa__init(pa_module *m) {
if (pa_modargs_get_value(ma, "channels", NULL) || pa_modargs_get_value(ma, "channel_map", NULL))
channels_set = true;
- latency_msec = DEFAULT_LATENCY_MSEC;
- if (pa_modargs_get_value_u32(ma, "latency_msec", &latency_msec) < 0 || latency_msec < 1 || latency_msec > 30000) {
+ buffer_latency_msec = 0;
+ if (pa_modargs_get_value_u32(ma, "buffer_latency_msec", &buffer_latency_msec) < 0 || buffer_latency_msec > 30000) {
+ pa_log_info("Invalid buffer latency specification");
+ goto fail;
+ }
+ else if (buffer_latency_msec > 0)
+ buffer_latency_set = true;
+
+ latency_msec = 0;
+ if (!buffer_latency_set)
+ latency_msec = DEFAULT_LATENCY_MSEC;
+ if (pa_modargs_get_value_u32(ma, "latency_msec", &latency_msec) < 0 || latency_msec > 30000) {
pa_log("Invalid latency specification");
goto fail;
}
@@ -818,6 +1049,18 @@ int pa__init(pa_module *m) {
u->core = m->core;
u->module = m;
u->latency = (pa_usec_t) latency_msec * PA_USEC_PER_MSEC;
+ if (buffer_latency_set)
+ u->initial_buffer_latency = (pa_usec_t) buffer_latency_msec * PA_USEC_PER_MSEC;
+ else
+ u->initial_buffer_latency = PA_MAX(u->latency / 4, 1.667 * PA_USEC_PER_MSEC);
+ u->buffer_latency = u->initial_buffer_latency;
+ u->buffer_latency_set = buffer_latency_set;
+ u->sink_latency_sum = 0;
+ u->source_latency_sum = 0;
+ u->pop_called = false;
+ u->underruns = 0;
+ u->no_peeks = 0;
+ u->source_sink_changed = true;
adjust_time_sec = DEFAULT_ADJUST_TIME_USEC / PA_USEC_PER_SEC;
if (pa_modargs_get_value_u32(ma, "adjust_time", &adjust_time_sec) < 0) {
@@ -894,9 +1137,13 @@ int pa__init(pa_module *m) {
u->sink_input->may_move_to = sink_input_may_move_to_cb;
u->sink_input->moving = sink_input_moving_cb;
u->sink_input->suspend = sink_input_suspend_cb;
+ u->sink_input->update_sink_requested_latency = update_sink_requested_latency_cb;
u->sink_input->userdata = u;
- pa_sink_input_set_requested_latency(u->sink_input, u->latency/3);
+ if (u->latency < 4 * PA_USEC_PER_MSEC && !buffer_latency_set)
+ pa_log_warn("Latency limited to 4 ms, try buffer_latency_msec together with latency_msec if you know what you are doing");
+
+ set_sink_input_latency(u, u->sink_input->sink);
pa_source_output_new_data_init(&source_output_data);
source_output_data.driver = __FILE__;
@@ -941,13 +1188,13 @@ int pa__init(pa_module *m) {
u->source_output->kill = source_output_kill_cb;
u->source_output->attach = source_output_attach_cb;
u->source_output->detach = source_output_detach_cb;
- u->source_output->state_change = source_output_state_change_cb;
u->source_output->may_move_to = source_output_may_move_to_cb;
u->source_output->moving = source_output_moving_cb;
u->source_output->suspend = source_output_suspend_cb;
+ u->source_output->update_source_requested_latency = update_source_requested_latency_cb;
u->source_output->userdata = u;
- pa_source_output_set_requested_latency(u->source_output, u->latency/3);
+ set_source_output_latency(u, u->source_output->source);
pa_sink_input_get_silence(u->sink_input, &silence);
u->memblockq = pa_memblockq_new(
@@ -962,6 +1209,14 @@ int pa__init(pa_module *m) {
&silence); /* silence frame */
pa_memblock_unref(silence.memblock);
+ if(u->sink_input->sink->flags & PA_SINK_DYNAMIC_LATENCY)
+ memblockq_adjust(u, 0, true);
+ else
+ memblockq_adjust(u, (int32_t)(-u->configured_sink_latency / 4), true);
+
+ /* Initialize latency error (allow at least 1 ms latency offset) */
+ u->latency_error = 400.0 / get_requested_latency(u);
+
u->asyncmsgq = pa_asyncmsgq_new(0);
if (!pa_proplist_contains(u->source_output->proplist, PA_PROP_MEDIA_NAME))
--
2.1.4
