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-rw-r--r--media/libcubeb/test/test_loopback.cpp596
1 files changed, 596 insertions, 0 deletions
diff --git a/media/libcubeb/test/test_loopback.cpp b/media/libcubeb/test/test_loopback.cpp
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+++ b/media/libcubeb/test/test_loopback.cpp
@@ -0,0 +1,596 @@
+/*
+ * Copyright © 2017 Mozilla Foundation
+ *
+ * This program is made available under an ISC-style license. See the
+ * accompanying file LICENSE for details.
+ */
+
+ /* libcubeb api/function test. Requests a loopback device and checks that
+ output is being looped back to input. NOTE: Usage of output devices while
+ performing this test will cause flakey results! */
+#include "gtest/gtest.h"
+#if !defined(_XOPEN_SOURCE)
+#define _XOPEN_SOURCE 600
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <algorithm>
+#include <memory>
+#include <mutex>
+#include <string>
+#include "cubeb/cubeb.h"
+//#define ENABLE_NORMAL_LOG
+//#define ENABLE_VERBOSE_LOG
+#include "common.h"
+const uint32_t SAMPLE_FREQUENCY = 48000;
+const uint32_t TONE_FREQUENCY = 440;
+const double OUTPUT_AMPLITUDE = 0.25;
+const int32_t NUM_FRAMES_TO_OUTPUT = SAMPLE_FREQUENCY / 20; /* play ~50ms of samples */
+
+template<typename T> T ConvertSampleToOutput(double input);
+template<> float ConvertSampleToOutput(double input) { return float(input); }
+template<> short ConvertSampleToOutput(double input) { return short(input * 32767.0f); }
+
+template<typename T> double ConvertSampleFromOutput(T sample);
+template<> double ConvertSampleFromOutput(float sample) { return double(sample); }
+template<> double ConvertSampleFromOutput(short sample) { return double(sample / 32767.0); }
+
+/* Simple cross correlation to help find phase shift. Not a performant impl */
+std::vector<double> cross_correlate(std::vector<double> & f,
+ std::vector<double> & g,
+ size_t signal_length)
+{
+ /* the length we sweep our window through to find the cross correlation */
+ size_t sweep_length = f.size() - signal_length + 1;
+ std::vector<double> correlation;
+ correlation.reserve(sweep_length);
+ for (size_t i = 0; i < sweep_length; i++) {
+ double accumulator = 0.0;
+ for (size_t j = 0; j < signal_length; j++) {
+ accumulator += f.at(j) * g.at(i + j);
+ }
+ correlation.push_back(accumulator);
+ }
+ return correlation;
+}
+
+/* best effort discovery of phase shift between output and (looped) input*/
+size_t find_phase(std::vector<double> & output_frames,
+ std::vector<double> & input_frames,
+ size_t signal_length)
+{
+ std::vector<double> correlation = cross_correlate(output_frames, input_frames, signal_length);
+ size_t phase = 0;
+ double max_correlation = correlation.at(0);
+ for (size_t i = 1; i < correlation.size(); i++) {
+ if (correlation.at(i) > max_correlation) {
+ max_correlation = correlation.at(i);
+ phase = i;
+ }
+ }
+ return phase;
+}
+
+std::vector<double> normalize_frames(std::vector<double> & frames) {
+ double max = abs(*std::max_element(frames.begin(), frames.end(),
+ [](double a, double b) { return abs(a) < abs(b); }));
+ std::vector<double> normalized_frames;
+ normalized_frames.reserve(frames.size());
+ for (const double frame : frames) {
+ normalized_frames.push_back(frame / max);
+ }
+ return normalized_frames;
+}
+
+/* heuristic comparison of aligned output and input signals, gets flaky if TONE_FREQUENCY is too high */
+void compare_signals(std::vector<double> & output_frames,
+ std::vector<double> & input_frames)
+{
+ ASSERT_EQ(output_frames.size(), input_frames.size()) << "#Output frames != #input frames";
+ size_t num_frames = output_frames.size();
+ std::vector<double> normalized_output_frames = normalize_frames(output_frames);
+ std::vector<double> normalized_input_frames = normalize_frames(input_frames);
+
+ /* calculate mean absolute errors */
+ /* mean absolute errors between output and input */
+ double io_mas = 0.0;
+ /* mean absolute errors between output and silence */
+ double output_silence_mas = 0.0;
+ /* mean absolute errors between input and silence */
+ double input_silence_mas = 0.0;
+ for (size_t i = 0; i < num_frames; i++) {
+ io_mas += abs(normalized_output_frames.at(i) - normalized_input_frames.at(i));
+ output_silence_mas += abs(normalized_output_frames.at(i));
+ input_silence_mas += abs(normalized_input_frames.at(i));
+ }
+ io_mas /= num_frames;
+ output_silence_mas /= num_frames;
+ input_silence_mas /= num_frames;
+
+ ASSERT_LT(io_mas, output_silence_mas)
+ << "Error between output and input should be less than output and silence!";
+ ASSERT_LT(io_mas, input_silence_mas)
+ << "Error between output and input should be less than output and silence!";
+
+ /* make sure extrema are in (roughly) correct location */
+ /* number of maxima + minama expected in the frames*/
+ const long NUM_EXTREMA = 2 * TONE_FREQUENCY * NUM_FRAMES_TO_OUTPUT / SAMPLE_FREQUENCY;
+ /* expected index of first maxima */
+ const long FIRST_MAXIMUM_INDEX = SAMPLE_FREQUENCY / TONE_FREQUENCY / 4;
+ /* Threshold we expect all maxima and minima to be above or below. Ideally
+ the extrema would be 1 or -1, but particularly at the start of loopback
+ the values seen can be significantly lower. */
+ const double THRESHOLD = 0.5;
+
+ for (size_t i = 0; i < NUM_EXTREMA; i++) {
+ bool is_maximum = i % 2 == 0;
+ /* expected offset to current extreme: i * stide between extrema */
+ size_t offset = i * SAMPLE_FREQUENCY / TONE_FREQUENCY / 2;
+ if (is_maximum) {
+ ASSERT_GT(normalized_output_frames.at(FIRST_MAXIMUM_INDEX + offset), THRESHOLD)
+ << "Output frames have unexpected missing maximum!";
+ ASSERT_GT(normalized_input_frames.at(FIRST_MAXIMUM_INDEX + offset), THRESHOLD)
+ << "Input frames have unexpected missing maximum!";
+ } else {
+ ASSERT_LT(normalized_output_frames.at(FIRST_MAXIMUM_INDEX + offset), -THRESHOLD)
+ << "Output frames have unexpected missing minimum!";
+ ASSERT_LT(normalized_input_frames.at(FIRST_MAXIMUM_INDEX + offset), -THRESHOLD)
+ << "Input frames have unexpected missing minimum!";
+ }
+ }
+}
+
+struct user_state_loopback {
+ std::mutex user_state_mutex;
+ long position = 0;
+ /* track output */
+ std::vector<double> output_frames;
+ /* track input */
+ std::vector<double> input_frames;
+};
+
+template<typename T>
+long data_cb_loop_duplex(cubeb_stream * stream, void * user, const void * inputbuffer, void * outputbuffer, long nframes)
+{
+ struct user_state_loopback * u = (struct user_state_loopback *) user;
+ T * ib = (T *) inputbuffer;
+ T * ob = (T *) outputbuffer;
+
+ if (stream == NULL || inputbuffer == NULL || outputbuffer == NULL) {
+ return CUBEB_ERROR;
+ }
+
+ std::lock_guard<std::mutex> lock(u->user_state_mutex);
+ /* generate our test tone on the fly */
+ for (int i = 0; i < nframes; i++) {
+ double tone = 0.0;
+ if (u->position + i < NUM_FRAMES_TO_OUTPUT) {
+ /* generate sine wave */
+ tone = sin(2 * M_PI*(i + u->position) * TONE_FREQUENCY / SAMPLE_FREQUENCY);
+ tone *= OUTPUT_AMPLITUDE;
+ }
+ ob[i] = ConvertSampleToOutput<T>(tone);
+ u->output_frames.push_back(tone);
+ /* store any looped back output, may be silence */
+ u->input_frames.push_back(ConvertSampleFromOutput(ib[i]));
+ }
+
+ u->position += nframes;
+
+ return nframes;
+}
+
+template<typename T>
+long data_cb_loop_input_only(cubeb_stream * stream, void * user, const void * inputbuffer, void * outputbuffer, long nframes)
+{
+ struct user_state_loopback * u = (struct user_state_loopback *) user;
+ T * ib = (T *) inputbuffer;
+
+ if (outputbuffer != NULL) {
+ // Can't assert as it needs to return, so expect to fail instead
+ EXPECT_EQ(outputbuffer, (void *) NULL) << "outputbuffer should be null in input only callback";
+ return CUBEB_ERROR;
+ }
+
+ if (stream == NULL || inputbuffer == NULL) {
+ return CUBEB_ERROR;
+ }
+
+ std::lock_guard<std::mutex> lock(u->user_state_mutex);
+ for (int i = 0; i < nframes; i++) {
+ u->input_frames.push_back(ConvertSampleFromOutput(ib[i]));
+ }
+
+ return nframes;
+}
+
+template<typename T>
+long data_cb_playback(cubeb_stream * stream, void * user, const void * inputbuffer, void * outputbuffer, long nframes)
+{
+ struct user_state_loopback * u = (struct user_state_loopback *) user;
+ T * ob = (T *) outputbuffer;
+
+ if (stream == NULL || outputbuffer == NULL) {
+ return CUBEB_ERROR;
+ }
+
+ std::lock_guard<std::mutex> lock(u->user_state_mutex);
+ /* generate our test tone on the fly */
+ for (int i = 0; i < nframes; i++) {
+ double tone = 0.0;
+ if (u->position + i < NUM_FRAMES_TO_OUTPUT) {
+ /* generate sine wave */
+ tone = sin(2 * M_PI*(i + u->position) * TONE_FREQUENCY / SAMPLE_FREQUENCY);
+ tone *= OUTPUT_AMPLITUDE;
+ }
+ ob[i] = ConvertSampleToOutput<T>(tone);
+ u->output_frames.push_back(tone);
+ }
+
+ u->position += nframes;
+
+ return nframes;
+}
+
+void state_cb_loop(cubeb_stream * stream, void * /*user*/, cubeb_state state)
+{
+ if (stream == NULL)
+ return;
+
+ switch (state) {
+ case CUBEB_STATE_STARTED:
+ fprintf(stderr, "stream started\n"); break;
+ case CUBEB_STATE_STOPPED:
+ fprintf(stderr, "stream stopped\n"); break;
+ case CUBEB_STATE_DRAINED:
+ fprintf(stderr, "stream drained\n"); break;
+ default:
+ fprintf(stderr, "unknown stream state %d\n", state);
+ }
+
+ return;
+}
+
+void run_loopback_duplex_test(bool is_float)
+{
+ cubeb * ctx;
+ cubeb_stream * stream;
+ cubeb_stream_params input_params;
+ cubeb_stream_params output_params;
+ int r;
+ uint32_t latency_frames = 0;
+
+ r = common_init(&ctx, "Cubeb loopback example: duplex stream");
+ ASSERT_EQ(r, CUBEB_OK) << "Error initializing cubeb library";
+
+ std::unique_ptr<cubeb, decltype(&cubeb_destroy)>
+ cleanup_cubeb_at_exit(ctx, cubeb_destroy);
+
+ /* This test needs an available input device, skip it if this host does not
+ * have one. */
+ if (!can_run_audio_input_test(ctx)) {
+ return;
+ }
+
+ input_params.format = is_float ? CUBEB_SAMPLE_FLOAT32NE : CUBEB_SAMPLE_S16LE;
+ input_params.rate = SAMPLE_FREQUENCY;
+ input_params.channels = 1;
+ input_params.layout = CUBEB_LAYOUT_MONO;
+ input_params.prefs = CUBEB_STREAM_PREF_LOOPBACK;
+ output_params.format = is_float ? CUBEB_SAMPLE_FLOAT32NE : CUBEB_SAMPLE_S16LE;
+ output_params.rate = SAMPLE_FREQUENCY;
+ output_params.channels = 1;
+ output_params.layout = CUBEB_LAYOUT_MONO;
+ output_params.prefs = CUBEB_STREAM_PREF_NONE;
+
+ std::unique_ptr<user_state_loopback> user_data(new user_state_loopback());
+ ASSERT_TRUE(!!user_data) << "Error allocating user data";
+
+ r = cubeb_get_min_latency(ctx, &output_params, &latency_frames);
+ ASSERT_EQ(r, CUBEB_OK) << "Could not get minimal latency";
+
+ /* setup a duplex stream with loopback */
+ r = cubeb_stream_init(ctx, &stream, "Cubeb loopback",
+ NULL, &input_params, NULL, &output_params, latency_frames,
+ is_float ? data_cb_loop_duplex<float> : data_cb_loop_duplex<short>,
+ state_cb_loop, user_data.get());
+ ASSERT_EQ(r, CUBEB_OK) << "Error initializing cubeb stream";
+
+ std::unique_ptr<cubeb_stream, decltype(&cubeb_stream_destroy)>
+ cleanup_stream_at_exit(stream, cubeb_stream_destroy);
+
+ cubeb_stream_start(stream);
+ delay(300);
+ cubeb_stream_stop(stream);
+
+ /* access after stop should not happen, but lock just in case and to appease sanitization tools */
+ std::lock_guard<std::mutex> lock(user_data->user_state_mutex);
+ std::vector<double> & output_frames = user_data->output_frames;
+ std::vector<double> & input_frames = user_data->input_frames;
+ ASSERT_EQ(output_frames.size(), input_frames.size())
+ << "#Output frames != #input frames";
+
+ size_t phase = find_phase(user_data->output_frames, user_data->input_frames, NUM_FRAMES_TO_OUTPUT);
+
+ /* extract vectors of just the relevant signal from output and input */
+ auto output_frames_signal_start = output_frames.begin();
+ auto output_frames_signal_end = output_frames.begin() + NUM_FRAMES_TO_OUTPUT;
+ std::vector<double> trimmed_output_frames(output_frames_signal_start, output_frames_signal_end);
+ auto input_frames_signal_start = input_frames.begin() + phase;
+ auto input_frames_signal_end = input_frames.begin() + phase + NUM_FRAMES_TO_OUTPUT;
+ std::vector<double> trimmed_input_frames(input_frames_signal_start, input_frames_signal_end);
+
+ compare_signals(trimmed_output_frames, trimmed_input_frames);
+}
+
+TEST(cubeb, loopback_duplex)
+{
+ run_loopback_duplex_test(true);
+ run_loopback_duplex_test(false);
+}
+
+void run_loopback_separate_streams_test(bool is_float)
+{
+ cubeb * ctx;
+ cubeb_stream * input_stream;
+ cubeb_stream * output_stream;
+ cubeb_stream_params input_params;
+ cubeb_stream_params output_params;
+ int r;
+ uint32_t latency_frames = 0;
+
+ r = common_init(&ctx, "Cubeb loopback example: separate streams");
+ ASSERT_EQ(r, CUBEB_OK) << "Error initializing cubeb library";
+
+ std::unique_ptr<cubeb, decltype(&cubeb_destroy)>
+ cleanup_cubeb_at_exit(ctx, cubeb_destroy);
+
+ if (!can_run_audio_input_test(ctx)) {
+ return;
+ }
+
+ input_params.format = is_float ? CUBEB_SAMPLE_FLOAT32NE : CUBEB_SAMPLE_S16LE;
+ input_params.rate = SAMPLE_FREQUENCY;
+ input_params.channels = 1;
+ input_params.layout = CUBEB_LAYOUT_MONO;
+ input_params.prefs = CUBEB_STREAM_PREF_LOOPBACK;
+ output_params.format = is_float ? CUBEB_SAMPLE_FLOAT32NE : CUBEB_SAMPLE_S16LE;
+ output_params.rate = SAMPLE_FREQUENCY;
+ output_params.channels = 1;
+ output_params.layout = CUBEB_LAYOUT_MONO;
+ output_params.prefs = CUBEB_STREAM_PREF_NONE;
+
+ std::unique_ptr<user_state_loopback> user_data(new user_state_loopback());
+ ASSERT_TRUE(!!user_data) << "Error allocating user data";
+
+ r = cubeb_get_min_latency(ctx, &output_params, &latency_frames);
+ ASSERT_EQ(r, CUBEB_OK) << "Could not get minimal latency";
+
+ /* setup an input stream with loopback */
+ r = cubeb_stream_init(ctx, &input_stream, "Cubeb loopback input only",
+ NULL, &input_params, NULL, NULL, latency_frames,
+ is_float ? data_cb_loop_input_only<float> : data_cb_loop_input_only<short>,
+ state_cb_loop, user_data.get());
+ ASSERT_EQ(r, CUBEB_OK) << "Error initializing cubeb stream";
+
+ std::unique_ptr<cubeb_stream, decltype(&cubeb_stream_destroy)>
+ cleanup_input_stream_at_exit(input_stream, cubeb_stream_destroy);
+
+ /* setup an output stream */
+ r = cubeb_stream_init(ctx, &output_stream, "Cubeb loopback output only",
+ NULL, NULL, NULL, &output_params, latency_frames,
+ is_float ? data_cb_playback<float> : data_cb_playback<short>,
+ state_cb_loop, user_data.get());
+ ASSERT_EQ(r, CUBEB_OK) << "Error initializing cubeb stream";
+
+ std::unique_ptr<cubeb_stream, decltype(&cubeb_stream_destroy)>
+ cleanup_output_stream_at_exit(output_stream, cubeb_stream_destroy);
+
+ cubeb_stream_start(input_stream);
+ cubeb_stream_start(output_stream);
+ delay(300);
+ cubeb_stream_stop(output_stream);
+ cubeb_stream_stop(input_stream);
+
+ /* access after stop should not happen, but lock just in case and to appease sanitization tools */
+ std::lock_guard<std::mutex> lock(user_data->user_state_mutex);
+ std::vector<double> & output_frames = user_data->output_frames;
+ std::vector<double> & input_frames = user_data->input_frames;
+ ASSERT_LE(output_frames.size(), input_frames.size())
+ << "#Output frames should be less or equal to #input frames";
+
+ size_t phase = find_phase(user_data->output_frames, user_data->input_frames, NUM_FRAMES_TO_OUTPUT);
+
+ /* extract vectors of just the relevant signal from output and input */
+ auto output_frames_signal_start = output_frames.begin();
+ auto output_frames_signal_end = output_frames.begin() + NUM_FRAMES_TO_OUTPUT;
+ std::vector<double> trimmed_output_frames(output_frames_signal_start, output_frames_signal_end);
+ auto input_frames_signal_start = input_frames.begin() + phase;
+ auto input_frames_signal_end = input_frames.begin() + phase + NUM_FRAMES_TO_OUTPUT;
+ std::vector<double> trimmed_input_frames(input_frames_signal_start, input_frames_signal_end);
+
+ compare_signals(trimmed_output_frames, trimmed_input_frames);
+}
+
+TEST(cubeb, loopback_separate_streams)
+{
+ run_loopback_separate_streams_test(true);
+ run_loopback_separate_streams_test(false);
+}
+
+void run_loopback_silence_test(bool is_float)
+{
+ cubeb * ctx;
+ cubeb_stream * input_stream;
+ cubeb_stream_params input_params;
+ int r;
+ uint32_t latency_frames = 0;
+
+ r = common_init(&ctx, "Cubeb loopback example: record silence");
+ ASSERT_EQ(r, CUBEB_OK) << "Error initializing cubeb library";
+
+ std::unique_ptr<cubeb, decltype(&cubeb_destroy)>
+ cleanup_cubeb_at_exit(ctx, cubeb_destroy);
+
+ if (!can_run_audio_input_test(ctx)) {
+ return;
+ }
+
+ input_params.format = is_float ? CUBEB_SAMPLE_FLOAT32NE : CUBEB_SAMPLE_S16LE;
+ input_params.rate = SAMPLE_FREQUENCY;
+ input_params.channels = 1;
+ input_params.layout = CUBEB_LAYOUT_MONO;
+ input_params.prefs = CUBEB_STREAM_PREF_LOOPBACK;
+
+ std::unique_ptr<user_state_loopback> user_data(new user_state_loopback());
+ ASSERT_TRUE(!!user_data) << "Error allocating user data";
+
+ r = cubeb_get_min_latency(ctx, &input_params, &latency_frames);
+ ASSERT_EQ(r, CUBEB_OK) << "Could not get minimal latency";
+
+ /* setup an input stream with loopback */
+ r = cubeb_stream_init(ctx, &input_stream, "Cubeb loopback input only",
+ NULL, &input_params, NULL, NULL, latency_frames,
+ is_float ? data_cb_loop_input_only<float> : data_cb_loop_input_only<short>,
+ state_cb_loop, user_data.get());
+ ASSERT_EQ(r, CUBEB_OK) << "Error initializing cubeb stream";
+
+ std::unique_ptr<cubeb_stream, decltype(&cubeb_stream_destroy)>
+ cleanup_input_stream_at_exit(input_stream, cubeb_stream_destroy);
+
+ cubeb_stream_start(input_stream);
+ delay(300);
+ cubeb_stream_stop(input_stream);
+
+ /* access after stop should not happen, but lock just in case and to appease sanitization tools */
+ std::lock_guard<std::mutex> lock(user_data->user_state_mutex);
+ std::vector<double> & input_frames = user_data->input_frames;
+
+ /* expect to have at least ~50ms of frames */
+ ASSERT_GE(input_frames.size(), SAMPLE_FREQUENCY / 20);
+ double EPISILON = 0.0001;
+ /* frames should be 0.0, but use epsilon to avoid possible issues with impls
+ that may use ~0.0 silence values. */
+ for (double frame : input_frames) {
+ ASSERT_LT(abs(frame), EPISILON);
+ }
+}
+
+TEST(cubeb, loopback_silence)
+{
+ run_loopback_silence_test(true);
+ run_loopback_silence_test(false);
+}
+
+void run_loopback_device_selection_test(bool is_float)
+{
+ cubeb * ctx;
+ cubeb_device_collection collection;
+ cubeb_stream * input_stream;
+ cubeb_stream * output_stream;
+ cubeb_stream_params input_params;
+ cubeb_stream_params output_params;
+ int r;
+ uint32_t latency_frames = 0;
+
+ r = common_init(&ctx, "Cubeb loopback example: device selection, separate streams");
+ ASSERT_EQ(r, CUBEB_OK) << "Error initializing cubeb library";
+
+ std::unique_ptr<cubeb, decltype(&cubeb_destroy)>
+ cleanup_cubeb_at_exit(ctx, cubeb_destroy);
+
+ if (!can_run_audio_input_test(ctx)) {
+ return;
+ }
+
+ r = cubeb_enumerate_devices(ctx, CUBEB_DEVICE_TYPE_OUTPUT, &collection);
+ if (r == CUBEB_ERROR_NOT_SUPPORTED) {
+ fprintf(stderr, "Device enumeration not supported"
+ " for this backend, skipping this test.\n");
+ return;
+ }
+
+ ASSERT_EQ(r, CUBEB_OK) << "Error enumerating devices " << r;
+ /* get first preferred output device id */
+ std::string device_id;
+ for (size_t i = 0; i < collection.count; i++) {
+ if (collection.device[i].preferred) {
+ device_id = collection.device[i].device_id;
+ break;
+ }
+ }
+ cubeb_device_collection_destroy(ctx, &collection);
+ if (device_id.empty()) {
+ fprintf(stderr, "Could not find preferred device, aborting test.\n");
+ return;
+ }
+
+ input_params.format = is_float ? CUBEB_SAMPLE_FLOAT32NE : CUBEB_SAMPLE_S16LE;
+ input_params.rate = SAMPLE_FREQUENCY;
+ input_params.channels = 1;
+ input_params.layout = CUBEB_LAYOUT_MONO;
+ input_params.prefs = CUBEB_STREAM_PREF_LOOPBACK;
+ output_params.format = is_float ? CUBEB_SAMPLE_FLOAT32NE : CUBEB_SAMPLE_S16LE;
+ output_params.rate = SAMPLE_FREQUENCY;
+ output_params.channels = 1;
+ output_params.layout = CUBEB_LAYOUT_MONO;
+ output_params.prefs = CUBEB_STREAM_PREF_NONE;
+
+ std::unique_ptr<user_state_loopback> user_data(new user_state_loopback());
+ ASSERT_TRUE(!!user_data) << "Error allocating user data";
+
+ r = cubeb_get_min_latency(ctx, &output_params, &latency_frames);
+ ASSERT_EQ(r, CUBEB_OK) << "Could not get minimal latency";
+
+ /* setup an input stream with loopback */
+ r = cubeb_stream_init(ctx, &input_stream, "Cubeb loopback input only",
+ device_id.c_str(), &input_params, NULL, NULL, latency_frames,
+ is_float ? data_cb_loop_input_only<float> : data_cb_loop_input_only<short>,
+ state_cb_loop, user_data.get());
+ ASSERT_EQ(r, CUBEB_OK) << "Error initializing cubeb stream";
+
+ std::unique_ptr<cubeb_stream, decltype(&cubeb_stream_destroy)>
+ cleanup_input_stream_at_exit(input_stream, cubeb_stream_destroy);
+
+ /* setup an output stream */
+ r = cubeb_stream_init(ctx, &output_stream, "Cubeb loopback output only",
+ NULL, NULL, device_id.c_str(), &output_params, latency_frames,
+ is_float ? data_cb_playback<float> : data_cb_playback<short>,
+ state_cb_loop, user_data.get());
+ ASSERT_EQ(r, CUBEB_OK) << "Error initializing cubeb stream";
+
+ std::unique_ptr<cubeb_stream, decltype(&cubeb_stream_destroy)>
+ cleanup_output_stream_at_exit(output_stream, cubeb_stream_destroy);
+
+ cubeb_stream_start(input_stream);
+ cubeb_stream_start(output_stream);
+ delay(300);
+ cubeb_stream_stop(output_stream);
+ cubeb_stream_stop(input_stream);
+
+ /* access after stop should not happen, but lock just in case and to appease sanitization tools */
+ std::lock_guard<std::mutex> lock(user_data->user_state_mutex);
+ std::vector<double> & output_frames = user_data->output_frames;
+ std::vector<double> & input_frames = user_data->input_frames;
+ ASSERT_LE(output_frames.size(), input_frames.size())
+ << "#Output frames should be less or equal to #input frames";
+
+ size_t phase = find_phase(user_data->output_frames, user_data->input_frames, NUM_FRAMES_TO_OUTPUT);
+
+ /* extract vectors of just the relevant signal from output and input */
+ auto output_frames_signal_start = output_frames.begin();
+ auto output_frames_signal_end = output_frames.begin() + NUM_FRAMES_TO_OUTPUT;
+ std::vector<double> trimmed_output_frames(output_frames_signal_start, output_frames_signal_end);
+ auto input_frames_signal_start = input_frames.begin() + phase;
+ auto input_frames_signal_end = input_frames.begin() + phase + NUM_FRAMES_TO_OUTPUT;
+ std::vector<double> trimmed_input_frames(input_frames_signal_start, input_frames_signal_end);
+
+ compare_signals(trimmed_output_frames, trimmed_input_frames);
+}
+
+TEST(cubeb, loopback_device_selection)
+{
+ run_loopback_device_selection_test(true);
+ run_loopback_device_selection_test(false);
+}