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-rw-r--r--src/modules/echo-cancel/webrtc.cc594
1 files changed, 594 insertions, 0 deletions
diff --git a/src/modules/echo-cancel/webrtc.cc b/src/modules/echo-cancel/webrtc.cc
new file mode 100644
index 0000000..ec3ba06
--- /dev/null
+++ b/src/modules/echo-cancel/webrtc.cc
@@ -0,0 +1,594 @@
+/***
+ This file is part of PulseAudio.
+
+ Copyright 2011 Collabora Ltd.
+ 2015 Aldebaran SoftBank Group
+
+ Contributor: Arun Raghavan <mail@arunraghavan.net>
+
+ PulseAudio is free software; you can redistribute it and/or modify
+ it under the terms of the GNU Lesser General Public License as published
+ by the Free Software Foundation; either version 2.1 of the License,
+ or (at your option) any later version.
+
+ PulseAudio is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <pulse/cdecl.h>
+
+PA_C_DECL_BEGIN
+#include <pulsecore/core-util.h>
+#include <pulsecore/modargs.h>
+
+#include <pulse/timeval.h>
+#include "echo-cancel.h"
+PA_C_DECL_END
+
+#include <webrtc/modules/audio_processing/include/audio_processing.h>
+#include <webrtc/modules/interface/module_common_types.h>
+#include <webrtc/system_wrappers/include/trace.h>
+
+#define BLOCK_SIZE_US 10000
+
+#define DEFAULT_HIGH_PASS_FILTER true
+#define DEFAULT_NOISE_SUPPRESSION true
+#define DEFAULT_ANALOG_GAIN_CONTROL true
+#define DEFAULT_DIGITAL_GAIN_CONTROL false
+#define DEFAULT_MOBILE false
+#define DEFAULT_ROUTING_MODE "speakerphone"
+#define DEFAULT_COMFORT_NOISE true
+#define DEFAULT_DRIFT_COMPENSATION false
+#define DEFAULT_VAD true
+#define DEFAULT_EXTENDED_FILTER false
+#define DEFAULT_INTELLIGIBILITY_ENHANCER false
+#define DEFAULT_EXPERIMENTAL_AGC false
+#define DEFAULT_AGC_START_VOLUME 85
+#define DEFAULT_BEAMFORMING false
+#define DEFAULT_TRACE false
+
+#define WEBRTC_AGC_MAX_VOLUME 255
+
+static const char* const valid_modargs[] = {
+ "high_pass_filter",
+ "noise_suppression",
+ "analog_gain_control",
+ "digital_gain_control",
+ "mobile",
+ "routing_mode",
+ "comfort_noise",
+ "drift_compensation",
+ "voice_detection",
+ "extended_filter",
+ "intelligibility_enhancer",
+ "experimental_agc",
+ "agc_start_volume",
+ "beamforming",
+ "mic_geometry", /* documented in parse_mic_geometry() */
+ "target_direction", /* documented in parse_mic_geometry() */
+ "trace",
+ NULL
+};
+
+static int routing_mode_from_string(const char *rmode) {
+ if (pa_streq(rmode, "quiet-earpiece-or-headset"))
+ return webrtc::EchoControlMobile::kQuietEarpieceOrHeadset;
+ else if (pa_streq(rmode, "earpiece"))
+ return webrtc::EchoControlMobile::kEarpiece;
+ else if (pa_streq(rmode, "loud-earpiece"))
+ return webrtc::EchoControlMobile::kLoudEarpiece;
+ else if (pa_streq(rmode, "speakerphone"))
+ return webrtc::EchoControlMobile::kSpeakerphone;
+ else if (pa_streq(rmode, "loud-speakerphone"))
+ return webrtc::EchoControlMobile::kLoudSpeakerphone;
+ else
+ return -1;
+}
+
+class PaWebrtcTraceCallback : public webrtc::TraceCallback {
+ void Print(webrtc::TraceLevel level, const char *message, int length)
+ {
+ if (level & webrtc::kTraceError || level & webrtc::kTraceCritical)
+ pa_log(message);
+ else if (level & webrtc::kTraceWarning)
+ pa_log_warn(message);
+ else if (level & webrtc::kTraceInfo)
+ pa_log_info(message);
+ else
+ pa_log_debug(message);
+ }
+};
+
+static int webrtc_volume_from_pa(pa_volume_t v)
+{
+ return (v * WEBRTC_AGC_MAX_VOLUME) / PA_VOLUME_NORM;
+}
+
+static pa_volume_t webrtc_volume_to_pa(int v)
+{
+ return (v * PA_VOLUME_NORM) / WEBRTC_AGC_MAX_VOLUME;
+}
+
+static void webrtc_ec_fixate_spec(pa_sample_spec *rec_ss, pa_channel_map *rec_map,
+ pa_sample_spec *play_ss, pa_channel_map *play_map,
+ pa_sample_spec *out_ss, pa_channel_map *out_map,
+ bool beamforming)
+{
+ rec_ss->format = PA_SAMPLE_FLOAT32NE;
+ play_ss->format = PA_SAMPLE_FLOAT32NE;
+
+ /* AudioProcessing expects one of the following rates */
+ if (rec_ss->rate >= 48000)
+ rec_ss->rate = 48000;
+ else if (rec_ss->rate >= 32000)
+ rec_ss->rate = 32000;
+ else if (rec_ss->rate >= 16000)
+ rec_ss->rate = 16000;
+ else
+ rec_ss->rate = 8000;
+
+ *out_ss = *rec_ss;
+ *out_map = *rec_map;
+
+ if (beamforming) {
+ /* The beamformer gives us a single channel */
+ out_ss->channels = 1;
+ pa_channel_map_init_mono(out_map);
+ }
+
+ /* Playback stream rate needs to be the same as capture */
+ play_ss->rate = rec_ss->rate;
+}
+
+static bool parse_point(const char **point, float (&f)[3]) {
+ int ret, length;
+
+ ret = sscanf(*point, "%g,%g,%g%n", &f[0], &f[1], &f[2], &length);
+ if (ret != 3)
+ return false;
+
+ /* Consume the bytes we've read so far */
+ *point += length;
+
+ return true;
+}
+
+static bool parse_mic_geometry(const char **mic_geometry, std::vector<webrtc::Point>& geometry) {
+ /* The microphone geometry is expressed as cartesian point form:
+ * x1,y1,z1,x2,y2,z2,...
+ *
+ * Where x1,y1,z1 is the position of the first microphone with regards to
+ * the array's "center", x2,y2,z2 the position of the second, and so on.
+ *
+ * 'x' is the horizontal coordinate, with positive values being to the
+ * right from the mic array's perspective.
+ *
+ * 'y' is the depth coordinate, with positive values being in front of the
+ * array.
+ *
+ * 'z' is the vertical coordinate, with positive values being above the
+ * array.
+ *
+ * All distances are in meters.
+ */
+
+ /* The target direction is expected to be in spherical point form:
+ * a,e,r
+ *
+ * Where 'a' is the azimuth of the target point relative to the center of
+ * the array, 'e' its elevation, and 'r' the radius.
+ *
+ * 0 radians azimuth is to the right of the array, and positive angles
+ * move in a counter-clockwise direction.
+ *
+ * 0 radians elevation is horizontal w.r.t. the array, and positive
+ * angles go upwards.
+ *
+ * radius is distance from the array center in meters.
+ */
+
+ long unsigned int i;
+ float f[3];
+
+ for (i = 0; i < geometry.size(); i++) {
+ if (!parse_point(mic_geometry, f)) {
+ pa_log("Failed to parse channel %lu in mic_geometry", i);
+ return false;
+ }
+
+ /* Except for the last point, we should have a trailing comma */
+ if (i != geometry.size() - 1) {
+ if (**mic_geometry != ',') {
+ pa_log("Failed to parse channel %lu in mic_geometry", i);
+ return false;
+ }
+
+ (*mic_geometry)++;
+ }
+
+ pa_log_debug("Got mic #%lu position: (%g, %g, %g)", i, f[0], f[1], f[2]);
+
+ geometry[i].c[0] = f[0];
+ geometry[i].c[1] = f[1];
+ geometry[i].c[2] = f[2];
+ }
+
+ if (**mic_geometry != '\0') {
+ pa_log("Failed to parse mic_geometry value: more parameters than expected");
+ return false;
+ }
+
+ return true;
+}
+
+bool pa_webrtc_ec_init(pa_core *c, pa_echo_canceller *ec,
+ pa_sample_spec *rec_ss, pa_channel_map *rec_map,
+ pa_sample_spec *play_ss, pa_channel_map *play_map,
+ pa_sample_spec *out_ss, pa_channel_map *out_map,
+ uint32_t *nframes, const char *args) {
+ webrtc::AudioProcessing *apm = NULL;
+ webrtc::ProcessingConfig pconfig;
+ webrtc::Config config;
+ bool hpf, ns, agc, dgc, mobile, cn, vad, ext_filter, intelligibility, experimental_agc, beamforming;
+ int rm = -1, i;
+ uint32_t agc_start_volume;
+ pa_modargs *ma;
+ bool trace = false;
+
+ if (!(ma = pa_modargs_new(args, valid_modargs))) {
+ pa_log("Failed to parse submodule arguments.");
+ goto fail;
+ }
+
+ hpf = DEFAULT_HIGH_PASS_FILTER;
+ if (pa_modargs_get_value_boolean(ma, "high_pass_filter", &hpf) < 0) {
+ pa_log("Failed to parse high_pass_filter value");
+ goto fail;
+ }
+
+ ns = DEFAULT_NOISE_SUPPRESSION;
+ if (pa_modargs_get_value_boolean(ma, "noise_suppression", &ns) < 0) {
+ pa_log("Failed to parse noise_suppression value");
+ goto fail;
+ }
+
+ agc = DEFAULT_ANALOG_GAIN_CONTROL;
+ if (pa_modargs_get_value_boolean(ma, "analog_gain_control", &agc) < 0) {
+ pa_log("Failed to parse analog_gain_control value");
+ goto fail;
+ }
+
+ dgc = agc ? false : DEFAULT_DIGITAL_GAIN_CONTROL;
+ if (pa_modargs_get_value_boolean(ma, "digital_gain_control", &dgc) < 0) {
+ pa_log("Failed to parse digital_gain_control value");
+ goto fail;
+ }
+
+ if (agc && dgc) {
+ pa_log("You must pick only one between analog and digital gain control");
+ goto fail;
+ }
+
+ mobile = DEFAULT_MOBILE;
+ if (pa_modargs_get_value_boolean(ma, "mobile", &mobile) < 0) {
+ pa_log("Failed to parse mobile value");
+ goto fail;
+ }
+
+ ec->params.drift_compensation = DEFAULT_DRIFT_COMPENSATION;
+ if (pa_modargs_get_value_boolean(ma, "drift_compensation", &ec->params.drift_compensation) < 0) {
+ pa_log("Failed to parse drift_compensation value");
+ goto fail;
+ }
+
+ if (mobile) {
+ if (ec->params.drift_compensation) {
+ pa_log("Can't use drift_compensation in mobile mode");
+ goto fail;
+ }
+
+ if ((rm = routing_mode_from_string(pa_modargs_get_value(ma, "routing_mode", DEFAULT_ROUTING_MODE))) < 0) {
+ pa_log("Failed to parse routing_mode value");
+ goto fail;
+ }
+
+ cn = DEFAULT_COMFORT_NOISE;
+ if (pa_modargs_get_value_boolean(ma, "comfort_noise", &cn) < 0) {
+ pa_log("Failed to parse cn value");
+ goto fail;
+ }
+ } else {
+ if (pa_modargs_get_value(ma, "comfort_noise", NULL) || pa_modargs_get_value(ma, "routing_mode", NULL)) {
+ pa_log("The routing_mode and comfort_noise options are only valid with mobile=true");
+ goto fail;
+ }
+ }
+
+ vad = DEFAULT_VAD;
+ if (pa_modargs_get_value_boolean(ma, "voice_detection", &vad) < 0) {
+ pa_log("Failed to parse voice_detection value");
+ goto fail;
+ }
+
+ ext_filter = DEFAULT_EXTENDED_FILTER;
+ if (pa_modargs_get_value_boolean(ma, "extended_filter", &ext_filter) < 0) {
+ pa_log("Failed to parse extended_filter value");
+ goto fail;
+ }
+
+ intelligibility = DEFAULT_INTELLIGIBILITY_ENHANCER;
+ if (pa_modargs_get_value_boolean(ma, "intelligibility_enhancer", &intelligibility) < 0) {
+ pa_log("Failed to parse intelligibility_enhancer value");
+ goto fail;
+ }
+
+ experimental_agc = DEFAULT_EXPERIMENTAL_AGC;
+ if (pa_modargs_get_value_boolean(ma, "experimental_agc", &experimental_agc) < 0) {
+ pa_log("Failed to parse experimental_agc value");
+ goto fail;
+ }
+
+ agc_start_volume = DEFAULT_AGC_START_VOLUME;
+ if (pa_modargs_get_value_u32(ma, "agc_start_volume", &agc_start_volume) < 0) {
+ pa_log("Failed to parse agc_start_volume value");
+ goto fail;
+ }
+ if (agc_start_volume > WEBRTC_AGC_MAX_VOLUME) {
+ pa_log("AGC start volume must not exceed %u", WEBRTC_AGC_MAX_VOLUME);
+ goto fail;
+ }
+ ec->params.webrtc.agc_start_volume = agc_start_volume;
+
+ beamforming = DEFAULT_BEAMFORMING;
+ if (pa_modargs_get_value_boolean(ma, "beamforming", &beamforming) < 0) {
+ pa_log("Failed to parse beamforming value");
+ goto fail;
+ }
+
+ if (ext_filter)
+ config.Set<webrtc::ExtendedFilter>(new webrtc::ExtendedFilter(true));
+ if (intelligibility)
+ pa_log_warn("The intelligibility enhancer is not currently supported");
+ if (experimental_agc)
+ config.Set<webrtc::ExperimentalAgc>(new webrtc::ExperimentalAgc(true, ec->params.webrtc.agc_start_volume));
+
+ trace = DEFAULT_TRACE;
+ if (pa_modargs_get_value_boolean(ma, "trace", &trace) < 0) {
+ pa_log("Failed to parse trace value");
+ goto fail;
+ }
+
+ if (trace) {
+ webrtc::Trace::CreateTrace();
+ webrtc::Trace::set_level_filter(webrtc::kTraceAll);
+ ec->params.webrtc.trace_callback = new PaWebrtcTraceCallback();
+ webrtc::Trace::SetTraceCallback((PaWebrtcTraceCallback *) ec->params.webrtc.trace_callback);
+ }
+
+ webrtc_ec_fixate_spec(rec_ss, rec_map, play_ss, play_map, out_ss, out_map, beamforming);
+
+ /* We do this after fixate because we need the capture channel count */
+ if (beamforming) {
+ std::vector<webrtc::Point> geometry(rec_ss->channels);
+ webrtc::SphericalPointf direction(0.0f, 0.0f, 0.0f);
+ const char *mic_geometry, *target_direction;
+
+ if (!(mic_geometry = pa_modargs_get_value(ma, "mic_geometry", NULL))) {
+ pa_log("mic_geometry must be set if beamforming is enabled");
+ goto fail;
+ }
+
+ if (!parse_mic_geometry(&mic_geometry, geometry)) {
+ pa_log("Failed to parse mic_geometry value");
+ goto fail;
+ }
+
+ if ((target_direction = pa_modargs_get_value(ma, "target_direction", NULL))) {
+ float f[3];
+
+ if (!parse_point(&target_direction, f)) {
+ pa_log("Failed to parse target_direction value");
+ goto fail;
+ }
+
+ if (*target_direction != '\0') {
+ pa_log("Failed to parse target_direction value: more parameters than expected");
+ goto fail;
+ }
+
+#define IS_ZERO(f) ((f) < 0.000001 && (f) > -0.000001)
+
+ if (!IS_ZERO(f[1]) || !IS_ZERO(f[2])) {
+ pa_log("The beamformer currently only supports targeting along the azimuth");
+ goto fail;
+ }
+
+ direction.s[0] = f[0];
+ direction.s[1] = f[1];
+ direction.s[2] = f[2];
+ }
+
+ if (!target_direction)
+ config.Set<webrtc::Beamforming>(new webrtc::Beamforming(true, geometry));
+ else
+ config.Set<webrtc::Beamforming>(new webrtc::Beamforming(true, geometry, direction));
+ }
+
+ apm = webrtc::AudioProcessing::Create(config);
+
+ pconfig = {
+ webrtc::StreamConfig(rec_ss->rate, rec_ss->channels, false), /* input stream */
+ webrtc::StreamConfig(out_ss->rate, out_ss->channels, false), /* output stream */
+ webrtc::StreamConfig(play_ss->rate, play_ss->channels, false), /* reverse input stream */
+ webrtc::StreamConfig(play_ss->rate, play_ss->channels, false), /* reverse output stream */
+ };
+ if (apm->Initialize(pconfig) != webrtc::AudioProcessing::kNoError) {
+ pa_log("Error initialising audio processing module");
+ goto fail;
+ }
+
+ if (hpf)
+ apm->high_pass_filter()->Enable(true);
+
+ if (!mobile) {
+ apm->echo_cancellation()->enable_drift_compensation(ec->params.drift_compensation);
+ apm->echo_cancellation()->Enable(true);
+ } else {
+ apm->echo_control_mobile()->set_routing_mode(static_cast<webrtc::EchoControlMobile::RoutingMode>(rm));
+ apm->echo_control_mobile()->enable_comfort_noise(cn);
+ apm->echo_control_mobile()->Enable(true);
+ }
+
+ if (ns) {
+ apm->noise_suppression()->set_level(webrtc::NoiseSuppression::kHigh);
+ apm->noise_suppression()->Enable(true);
+ }
+
+ if (agc || dgc) {
+ if (mobile && rm <= webrtc::EchoControlMobile::kEarpiece) {
+ /* Maybe this should be a knob, but we've got a lot of knobs already */
+ apm->gain_control()->set_mode(webrtc::GainControl::kFixedDigital);
+ ec->params.webrtc.agc = false;
+ } else if (dgc) {
+ apm->gain_control()->set_mode(webrtc::GainControl::kAdaptiveDigital);
+ ec->params.webrtc.agc = false;
+ } else {
+ apm->gain_control()->set_mode(webrtc::GainControl::kAdaptiveAnalog);
+ if (apm->gain_control()->set_analog_level_limits(0, WEBRTC_AGC_MAX_VOLUME) !=
+ webrtc::AudioProcessing::kNoError) {
+ pa_log("Failed to initialise AGC");
+ goto fail;
+ }
+ ec->params.webrtc.agc = true;
+ }
+
+ apm->gain_control()->Enable(true);
+ }
+
+ if (vad)
+ apm->voice_detection()->Enable(true);
+
+ ec->params.webrtc.apm = apm;
+ ec->params.webrtc.rec_ss = *rec_ss;
+ ec->params.webrtc.play_ss = *play_ss;
+ ec->params.webrtc.out_ss = *out_ss;
+ ec->params.webrtc.blocksize = (uint64_t) out_ss->rate * BLOCK_SIZE_US / PA_USEC_PER_SEC;
+ *nframes = ec->params.webrtc.blocksize;
+ ec->params.webrtc.first = true;
+
+ for (i = 0; i < rec_ss->channels; i++)
+ ec->params.webrtc.rec_buffer[i] = pa_xnew(float, *nframes);
+ for (i = 0; i < play_ss->channels; i++)
+ ec->params.webrtc.play_buffer[i] = pa_xnew(float, *nframes);
+
+ pa_modargs_free(ma);
+ return true;
+
+fail:
+ if (ma)
+ pa_modargs_free(ma);
+ if (ec->params.webrtc.trace_callback) {
+ webrtc::Trace::ReturnTrace();
+ delete ((PaWebrtcTraceCallback *) ec->params.webrtc.trace_callback);
+ } if (apm)
+ delete apm;
+
+ return false;
+}
+
+void pa_webrtc_ec_play(pa_echo_canceller *ec, const uint8_t *play) {
+ webrtc::AudioProcessing *apm = (webrtc::AudioProcessing*)ec->params.webrtc.apm;
+ const pa_sample_spec *ss = &ec->params.webrtc.play_ss;
+ int n = ec->params.webrtc.blocksize;
+ float **buf = ec->params.webrtc.play_buffer;
+ webrtc::StreamConfig config(ss->rate, ss->channels, false);
+
+ pa_deinterleave(play, (void **) buf, ss->channels, pa_sample_size(ss), n);
+
+ pa_assert_se(apm->ProcessReverseStream(buf, config, config, buf) == webrtc::AudioProcessing::kNoError);
+
+ /* FIXME: If ProcessReverseStream() makes any changes to the audio, such as
+ * applying intelligibility enhancement, those changes don't have any
+ * effect. This function is called at the source side, but the processing
+ * would have to be done in the sink to be able to feed the processed audio
+ * to speakers. */
+}
+
+void pa_webrtc_ec_record(pa_echo_canceller *ec, const uint8_t *rec, uint8_t *out) {
+ webrtc::AudioProcessing *apm = (webrtc::AudioProcessing*)ec->params.webrtc.apm;
+ const pa_sample_spec *rec_ss = &ec->params.webrtc.rec_ss;
+ const pa_sample_spec *out_ss = &ec->params.webrtc.out_ss;
+ float **buf = ec->params.webrtc.rec_buffer;
+ int n = ec->params.webrtc.blocksize;
+ int old_volume, new_volume;
+ webrtc::StreamConfig rec_config(rec_ss->rate, rec_ss->channels, false);
+ webrtc::StreamConfig out_config(out_ss->rate, out_ss->channels, false);
+
+ pa_deinterleave(rec, (void **) buf, rec_ss->channels, pa_sample_size(rec_ss), n);
+
+ if (ec->params.webrtc.agc) {
+ pa_volume_t v = pa_echo_canceller_get_capture_volume(ec);
+ old_volume = webrtc_volume_from_pa(v);
+ apm->gain_control()->set_stream_analog_level(old_volume);
+ }
+
+ apm->set_stream_delay_ms(0);
+ pa_assert_se(apm->ProcessStream(buf, rec_config, out_config, buf) == webrtc::AudioProcessing::kNoError);
+
+ if (ec->params.webrtc.agc) {
+ if (PA_UNLIKELY(ec->params.webrtc.first)) {
+ /* We start at a sane default volume (taken from the Chromium
+ * condition on the experimental AGC in audio_processing.h). This is
+ * needed to make sure that there's enough energy in the capture
+ * signal for the AGC to work */
+ ec->params.webrtc.first = false;
+ new_volume = ec->params.webrtc.agc_start_volume;
+ } else {
+ new_volume = apm->gain_control()->stream_analog_level();
+ }
+
+ if (old_volume != new_volume)
+ pa_echo_canceller_set_capture_volume(ec, webrtc_volume_to_pa(new_volume));
+ }
+
+ pa_interleave((const void **) buf, out_ss->channels, out, pa_sample_size(out_ss), n);
+}
+
+void pa_webrtc_ec_set_drift(pa_echo_canceller *ec, float drift) {
+ webrtc::AudioProcessing *apm = (webrtc::AudioProcessing*)ec->params.webrtc.apm;
+
+ apm->echo_cancellation()->set_stream_drift_samples(drift * ec->params.webrtc.blocksize);
+}
+
+void pa_webrtc_ec_run(pa_echo_canceller *ec, const uint8_t *rec, const uint8_t *play, uint8_t *out) {
+ pa_webrtc_ec_play(ec, play);
+ pa_webrtc_ec_record(ec, rec, out);
+}
+
+void pa_webrtc_ec_done(pa_echo_canceller *ec) {
+ int i;
+
+ if (ec->params.webrtc.trace_callback) {
+ webrtc::Trace::ReturnTrace();
+ delete ((PaWebrtcTraceCallback *) ec->params.webrtc.trace_callback);
+ }
+
+ if (ec->params.webrtc.apm) {
+ delete (webrtc::AudioProcessing*)ec->params.webrtc.apm;
+ ec->params.webrtc.apm = NULL;
+ }
+
+ for (i = 0; i < ec->params.webrtc.rec_ss.channels; i++)
+ pa_xfree(ec->params.webrtc.rec_buffer[i]);
+ for (i = 0; i < ec->params.webrtc.play_ss.channels; i++)
+ pa_xfree(ec->params.webrtc.play_buffer[i]);
+}