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media / base / channel_mixer_unittest.cc [blame]
// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/40285824): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif
#include "media/base/channel_mixer.h"
#include <memory>
#include "base/memory/raw_ptr.h"
#include "base/strings/stringprintf.h"
#include "media/base/audio_bus.h"
#include "media/base/audio_parameters.h"
#include "testing/gtest/include/gtest/gtest.h"
namespace media {
// Number of frames to test with.
enum { kFrames = 16 };
// Test all possible layout conversions can be constructed and mixed.
TEST(ChannelMixerTest, ConstructAllPossibleLayouts) {
for (ChannelLayout input_layout = CHANNEL_LAYOUT_MONO;
input_layout <= CHANNEL_LAYOUT_MAX;
input_layout = static_cast<ChannelLayout>(input_layout + 1)) {
for (ChannelLayout output_layout = CHANNEL_LAYOUT_MONO;
output_layout <= CHANNEL_LAYOUT_MAX;
output_layout = static_cast<ChannelLayout>(output_layout + 1)) {
// DISCRETE, BITSTREAM can't be tested here based on the current approach.
// CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC is deprecated.
// Stereo down mix should never be the output layout.
if (input_layout == CHANNEL_LAYOUT_BITSTREAM ||
input_layout == CHANNEL_LAYOUT_DISCRETE ||
input_layout == CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC ||
output_layout == CHANNEL_LAYOUT_BITSTREAM ||
output_layout == CHANNEL_LAYOUT_DISCRETE ||
output_layout == CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC ||
output_layout == CHANNEL_LAYOUT_STEREO_DOWNMIX) {
continue;
}
SCOPED_TRACE(base::StringPrintf(
"Input Layout: %d, Output Layout: %d", input_layout, output_layout));
ChannelMixer mixer(
input_layout, ChannelLayoutToChannelCount(input_layout),
output_layout, ChannelLayoutToChannelCount(output_layout));
std::unique_ptr<AudioBus> input_bus =
AudioBus::Create(ChannelLayoutToChannelCount(input_layout), kFrames);
std::unique_ptr<AudioBus> output_bus =
AudioBus::Create(ChannelLayoutToChannelCount(output_layout), kFrames);
for (int ch = 0; ch < input_bus->channels(); ++ch)
std::fill(input_bus->channel(ch), input_bus->channel(ch) + kFrames, 1);
mixer.Transform(input_bus.get(), output_bus.get());
}
}
}
struct ChannelMixerTestData {
ChannelMixerTestData(ChannelLayout input_layout, ChannelLayout output_layout,
const float* channel_values, int num_channel_values,
float scale)
: input_layout(input_layout),
output_layout(output_layout),
channel_values(channel_values),
num_channel_values(num_channel_values),
scale(scale) {
input_channels = ChannelLayoutToChannelCount(input_layout);
output_channels = ChannelLayoutToChannelCount(output_layout);
}
ChannelMixerTestData(ChannelLayout input_layout, int input_channels,
ChannelLayout output_layout, int output_channels,
const float* channel_values, int num_channel_values)
: input_layout(input_layout),
input_channels(input_channels),
output_layout(output_layout),
output_channels(output_channels),
channel_values(channel_values),
num_channel_values(num_channel_values),
scale(1.0f) {
}
std::string DebugString() const {
return base::StringPrintf(
"Input Layout: %d, Output Layout %d, Scale: %f", input_layout,
output_layout, scale);
}
ChannelLayout input_layout;
int input_channels;
ChannelLayout output_layout;
int output_channels;
raw_ptr<const float> channel_values;
int num_channel_values;
float scale;
};
std::ostream& operator<<(std::ostream& os, const ChannelMixerTestData& data) {
return os << data.DebugString();
}
class ChannelMixerTest : public testing::TestWithParam<ChannelMixerTestData> {};
// Verify channels are mixed and scaled correctly. The test only works if all
// output channels have the same value.
TEST_P(ChannelMixerTest, Mixing) {
ChannelLayout input_layout = GetParam().input_layout;
int input_channels = GetParam().input_channels;
std::unique_ptr<AudioBus> input_bus =
AudioBus::Create(input_channels, kFrames);
AudioParameters input_audio(AudioParameters::AUDIO_PCM_LINEAR,
{input_layout, input_channels},
AudioParameters::kAudioCDSampleRate, kFrames);
ChannelLayout output_layout = GetParam().output_layout;
int output_channels = GetParam().output_channels;
std::unique_ptr<AudioBus> output_bus =
AudioBus::Create(output_channels, kFrames);
AudioParameters output_audio(AudioParameters::AUDIO_PCM_LINEAR,
{output_layout, output_channels},
AudioParameters::kAudioCDSampleRate, kFrames);
const float* channel_values = GetParam().channel_values;
ASSERT_EQ(input_bus->channels(), GetParam().num_channel_values);
float expected_value = 0;
float scale = GetParam().scale;
for (int ch = 0; ch < input_bus->channels(); ++ch) {
std::fill(input_bus->channel(ch), input_bus->channel(ch) + kFrames,
channel_values[ch]);
expected_value += channel_values[ch] * scale;
}
ChannelMixer mixer(input_audio, output_audio);
mixer.Transform(input_bus.get(), output_bus.get());
// Validate the output channel
if (input_layout != CHANNEL_LAYOUT_DISCRETE) {
for (int ch = 0; ch < output_bus->channels(); ++ch) {
for (int frame = 0; frame < output_bus->frames(); ++frame) {
ASSERT_FLOAT_EQ(expected_value, output_bus->channel(ch)[frame]);
}
}
} else {
// Processing discrete mixing. If there is a matching input channel,
// then the output channel should be set. If no input channel,
// output channel should be 0
for (int ch = 0; ch < output_bus->channels(); ++ch) {
expected_value = (ch < input_channels) ? channel_values[ch] : 0;
for (int frame = 0; frame < output_bus->frames(); ++frame) {
ASSERT_FLOAT_EQ(expected_value, output_bus->channel(ch)[frame]);
}
}
}
}
static float kStereoToMonoValues[] = { 0.5f, 0.75f };
static float kMonoToStereoValues[] = { 0.5f };
// Zero the center channel since it will be mixed at scale 1 vs 1/sqrt(2).
static float kFiveOneToMonoValues[] = { 0.1f, 0.2f, 0.0f, 0.4f, 0.5f, 0.6f };
static float kFiveDiscreteValues[] = { 0.1f, 0.2f, 0.3f, 0.4f, 0.5f };
// Run through basic sanity tests for some common conversions.
INSTANTIATE_TEST_SUITE_P(
ChannelMixerTest,
ChannelMixerTest,
testing::Values(ChannelMixerTestData(CHANNEL_LAYOUT_STEREO,
CHANNEL_LAYOUT_MONO,
kStereoToMonoValues,
std::size(kStereoToMonoValues),
0.5f),
ChannelMixerTestData(CHANNEL_LAYOUT_MONO,
CHANNEL_LAYOUT_STEREO,
kMonoToStereoValues,
std::size(kMonoToStereoValues),
1.0f),
ChannelMixerTestData(CHANNEL_LAYOUT_5_1,
CHANNEL_LAYOUT_MONO,
kFiveOneToMonoValues,
std::size(kFiveOneToMonoValues),
ChannelMixer::kHalfPower),
ChannelMixerTestData(CHANNEL_LAYOUT_DISCRETE,
2,
CHANNEL_LAYOUT_DISCRETE,
2,
kStereoToMonoValues,
std::size(kStereoToMonoValues)),
ChannelMixerTestData(CHANNEL_LAYOUT_DISCRETE,
2,
CHANNEL_LAYOUT_DISCRETE,
5,
kStereoToMonoValues,
std::size(kStereoToMonoValues)),
ChannelMixerTestData(CHANNEL_LAYOUT_DISCRETE,
5,
CHANNEL_LAYOUT_DISCRETE,
2,
kFiveDiscreteValues,
std::size(kFiveDiscreteValues))));
} // namespace media