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/*
* 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 "cubeb/cubeb.h"
#include <algorithm>
#include <math.h>
#include <memory>
#include <mutex>
#include <stdio.h>
#include <stdlib.h>
#include <string>
// #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);
}