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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
#include "AudioMixer.h"
#include "gtest/gtest.h"
using mozilla::AudioDataValue;
using mozilla::AudioSampleFormat;
namespace audio_mixer {
struct MixerConsumer : public mozilla::MixerCallbackReceiver {
/* In this test, the different audio stream and channels are always created to
* cancel each other. */
void MixerCallback(mozilla::AudioChunk* aMixedBuffer, uint32_t aSampleRate) {
bool silent = true;
ASSERT_EQ(aMixedBuffer->mBufferFormat, mozilla::AUDIO_FORMAT_FLOAT32);
for (uint32_t c = 0; c < aMixedBuffer->ChannelCount(); c++) {
const float* channelData = aMixedBuffer->ChannelData<AudioDataValue>()[c];
for (uint32_t i = 0; i < aMixedBuffer->mDuration; i++) {
if (channelData[i] != 0.0) {
fprintf(stderr, "Sample at %d in channel %c is not silent: %f\n", i,
c, channelData[i]);
silent = false;
}
}
}
ASSERT_TRUE(silent);
}
};
/* Helper function to give us the maximum and minimum value that don't clip,
* for a given sample format (integer or floating-point). */
template <typename T>
T GetLowValue();
template <typename T>
T GetHighValue();
template <>
float GetLowValue<float>() {
return -1.0;
}
template <>
short GetLowValue<short>() {
return -INT16_MAX;
}
template <>
float GetHighValue<float>() {
return 1.0;
}
template <>
short GetHighValue<short>() {
return INT16_MAX;
}
void FillBuffer(AudioDataValue* aBuffer, uint32_t aLength,
AudioDataValue aValue) {
AudioDataValue* end = aBuffer + aLength;
while (aBuffer != end) {
*aBuffer++ = aValue;
}
}
TEST(AudioMixer, Test)
{
const uint32_t CHANNEL_LENGTH = 256;
const uint32_t AUDIO_RATE = 44100;
MixerConsumer consumer;
AudioDataValue a[CHANNEL_LENGTH * 2];
AudioDataValue b[CHANNEL_LENGTH * 2];
FillBuffer(a, CHANNEL_LENGTH, GetLowValue<AudioDataValue>());
FillBuffer(a + CHANNEL_LENGTH, CHANNEL_LENGTH,
GetHighValue<AudioDataValue>());
FillBuffer(b, CHANNEL_LENGTH, GetHighValue<AudioDataValue>());
FillBuffer(b + CHANNEL_LENGTH, CHANNEL_LENGTH, GetLowValue<AudioDataValue>());
{
int iterations = 2;
mozilla::AudioMixer mixer;
fprintf(stderr, "Test AudioMixer constant buffer length.\n");
while (iterations--) {
mixer.StartMixing();
mixer.Mix(a, 2, CHANNEL_LENGTH, AUDIO_RATE);
mixer.Mix(b, 2, CHANNEL_LENGTH, AUDIO_RATE);
consumer.MixerCallback(mixer.MixedChunk(), AUDIO_RATE);
}
}
{
mozilla::AudioMixer mixer;
fprintf(stderr, "Test AudioMixer variable buffer length.\n");
FillBuffer(a, CHANNEL_LENGTH / 2, GetLowValue<AudioDataValue>());
FillBuffer(a + CHANNEL_LENGTH / 2, CHANNEL_LENGTH / 2,
GetLowValue<AudioDataValue>());
FillBuffer(b, CHANNEL_LENGTH / 2, GetHighValue<AudioDataValue>());
FillBuffer(b + CHANNEL_LENGTH / 2, CHANNEL_LENGTH / 2,
GetHighValue<AudioDataValue>());
mixer.StartMixing();
mixer.Mix(a, 2, CHANNEL_LENGTH / 2, AUDIO_RATE);
mixer.Mix(b, 2, CHANNEL_LENGTH / 2, AUDIO_RATE);
consumer.MixerCallback(mixer.MixedChunk(), AUDIO_RATE);
FillBuffer(a, CHANNEL_LENGTH, GetLowValue<AudioDataValue>());
FillBuffer(a + CHANNEL_LENGTH, CHANNEL_LENGTH,
GetHighValue<AudioDataValue>());
FillBuffer(b, CHANNEL_LENGTH, GetHighValue<AudioDataValue>());
FillBuffer(b + CHANNEL_LENGTH, CHANNEL_LENGTH,
GetLowValue<AudioDataValue>());
mixer.StartMixing();
mixer.Mix(a, 2, CHANNEL_LENGTH, AUDIO_RATE);
mixer.Mix(b, 2, CHANNEL_LENGTH, AUDIO_RATE);
consumer.MixerCallback(mixer.MixedChunk(), AUDIO_RATE);
FillBuffer(a, CHANNEL_LENGTH / 2, GetLowValue<AudioDataValue>());
FillBuffer(a + CHANNEL_LENGTH / 2, CHANNEL_LENGTH / 2,
GetLowValue<AudioDataValue>());
FillBuffer(b, CHANNEL_LENGTH / 2, GetHighValue<AudioDataValue>());
FillBuffer(b + CHANNEL_LENGTH / 2, CHANNEL_LENGTH / 2,
GetHighValue<AudioDataValue>());
mixer.StartMixing();
mixer.Mix(a, 2, CHANNEL_LENGTH / 2, AUDIO_RATE);
mixer.Mix(b, 2, CHANNEL_LENGTH / 2, AUDIO_RATE);
consumer.MixerCallback(mixer.MixedChunk(), AUDIO_RATE);
}
FillBuffer(a, CHANNEL_LENGTH, GetLowValue<AudioDataValue>());
FillBuffer(b, CHANNEL_LENGTH, GetHighValue<AudioDataValue>());
{
mozilla::AudioMixer mixer;
fprintf(stderr, "Test AudioMixer variable channel count.\n");
mixer.StartMixing();
mixer.Mix(a, 1, CHANNEL_LENGTH, AUDIO_RATE);
mixer.Mix(b, 1, CHANNEL_LENGTH, AUDIO_RATE);
consumer.MixerCallback(mixer.MixedChunk(), AUDIO_RATE);
mixer.StartMixing();
mixer.Mix(a, 1, CHANNEL_LENGTH, AUDIO_RATE);
mixer.Mix(b, 1, CHANNEL_LENGTH, AUDIO_RATE);
consumer.MixerCallback(mixer.MixedChunk(), AUDIO_RATE);
mixer.StartMixing();
mixer.Mix(a, 1, CHANNEL_LENGTH, AUDIO_RATE);
mixer.Mix(b, 1, CHANNEL_LENGTH, AUDIO_RATE);
consumer.MixerCallback(mixer.MixedChunk(), AUDIO_RATE);
}
{
mozilla::AudioMixer mixer;
fprintf(stderr, "Test AudioMixer variable stream count.\n");
mixer.StartMixing();
mixer.Mix(a, 2, CHANNEL_LENGTH, AUDIO_RATE);
mixer.Mix(b, 2, CHANNEL_LENGTH, AUDIO_RATE);
consumer.MixerCallback(mixer.MixedChunk(), AUDIO_RATE);
mixer.StartMixing();
mixer.Mix(a, 2, CHANNEL_LENGTH, AUDIO_RATE);
mixer.Mix(b, 2, CHANNEL_LENGTH, AUDIO_RATE);
mixer.Mix(a, 2, CHANNEL_LENGTH, AUDIO_RATE);
mixer.Mix(b, 2, CHANNEL_LENGTH, AUDIO_RATE);
consumer.MixerCallback(mixer.MixedChunk(), AUDIO_RATE);
mixer.StartMixing();
mixer.Mix(a, 2, CHANNEL_LENGTH, AUDIO_RATE);
mixer.Mix(b, 2, CHANNEL_LENGTH, AUDIO_RATE);
consumer.MixerCallback(mixer.MixedChunk(), AUDIO_RATE);
}
}
} // namespace audio_mixer