// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/bind.h"
#include "base/bind_helpers.h"
#include "base/synchronization/condition_variable.h"
#include "base/synchronization/lock.h"
#include "base/sys_byteorder.h"
#include "base/time/time.h"
#include "media/cast/cast_config.h"
#include "media/cast/receiver/audio_decoder.h"
#include "media/cast/test/utility/audio_utility.h"
#include "media/cast/test/utility/standalone_cast_environment.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "third_party/opus/src/include/opus.h"
namespace media {
namespace cast {
namespace {
struct TestScenario {
transport::AudioCodec codec;
int num_channels;
int sampling_rate;
TestScenario(transport::AudioCodec c, int n, int s)
: codec(c), num_channels(n), sampling_rate(s) {}
};
} // namespace
class AudioDecoderTest : public ::testing::TestWithParam<TestScenario> {
public:
AudioDecoderTest()
: cast_environment_(new StandaloneCastEnvironment()),
cond_(&lock_) {}
protected:
virtual void SetUp() OVERRIDE {
audio_decoder_.reset(new AudioDecoder(cast_environment_,
GetParam().num_channels,
GetParam().sampling_rate,
GetParam().codec));
CHECK_EQ(STATUS_AUDIO_INITIALIZED, audio_decoder_->InitializationResult());
audio_bus_factory_.reset(
new TestAudioBusFactory(GetParam().num_channels,
GetParam().sampling_rate,
TestAudioBusFactory::kMiddleANoteFreq,
0.5f));
last_frame_id_ = 0;
seen_a_decoded_frame_ = false;
if (GetParam().codec == transport::kOpus) {
opus_encoder_memory_.reset(
new uint8[opus_encoder_get_size(GetParam().num_channels)]);
OpusEncoder* const opus_encoder =
reinterpret_cast<OpusEncoder*>(opus_encoder_memory_.get());
CHECK_EQ(OPUS_OK, opus_encoder_init(opus_encoder,
GetParam().sampling_rate,
GetParam().num_channels,
OPUS_APPLICATION_AUDIO));
CHECK_EQ(OPUS_OK,
opus_encoder_ctl(opus_encoder, OPUS_SET_BITRATE(OPUS_AUTO)));
}
total_audio_feed_in_ = base::TimeDelta();
total_audio_decoded_ = base::TimeDelta();
}
// Called from the unit test thread to create another EncodedFrame and push it
// into the decoding pipeline.
void FeedMoreAudio(const base::TimeDelta& duration,
int num_dropped_frames) {
// Prepare a simulated EncodedFrame to feed into the AudioDecoder.
scoped_ptr<transport::EncodedFrame> encoded_frame(
new transport::EncodedFrame());
encoded_frame->dependency = transport::EncodedFrame::KEY;
encoded_frame->frame_id = last_frame_id_ + 1 + num_dropped_frames;
encoded_frame->referenced_frame_id = encoded_frame->frame_id;
last_frame_id_ = encoded_frame->frame_id;
const scoped_ptr<AudioBus> audio_bus(
audio_bus_factory_->NextAudioBus(duration).Pass());
// Encode |audio_bus| into |encoded_frame->data|.
const int num_elements = audio_bus->channels() * audio_bus->frames();
std::vector<int16> interleaved(num_elements);
audio_bus->ToInterleaved(
audio_bus->frames(), sizeof(int16), &interleaved.front());
if (GetParam().codec == transport::kPcm16) {
encoded_frame->data.resize(num_elements * sizeof(int16));
int16* const pcm_data =
reinterpret_cast<int16*>(encoded_frame->mutable_bytes());
for (size_t i = 0; i < interleaved.size(); ++i)
pcm_data[i] = static_cast<int16>(base::HostToNet16(interleaved[i]));
} else if (GetParam().codec == transport::kOpus) {
OpusEncoder* const opus_encoder =
reinterpret_cast<OpusEncoder*>(opus_encoder_memory_.get());
const int kOpusEncodeBufferSize = 4000;
encoded_frame->data.resize(kOpusEncodeBufferSize);
const int payload_size =
opus_encode(opus_encoder,
&interleaved.front(),
audio_bus->frames(),
encoded_frame->mutable_bytes(),
encoded_frame->data.size());
CHECK_GT(payload_size, 1);
encoded_frame->data.resize(payload_size);
} else {
ASSERT_TRUE(false); // Not reached.
}
{
base::AutoLock auto_lock(lock_);
total_audio_feed_in_ += duration;
}
cast_environment_->PostTask(
CastEnvironment::MAIN,
FROM_HERE,
base::Bind(&AudioDecoder::DecodeFrame,
base::Unretained(audio_decoder_.get()),
base::Passed(&encoded_frame),
base::Bind(&AudioDecoderTest::OnDecodedFrame,
base::Unretained(this),
num_dropped_frames == 0)));
}
// Blocks the caller until all audio that has been feed in has been decoded.
void WaitForAllAudioToBeDecoded() {
DCHECK(!cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
base::AutoLock auto_lock(lock_);
while (total_audio_decoded_ < total_audio_feed_in_)
cond_.Wait();
EXPECT_EQ(total_audio_feed_in_.InMicroseconds(),
total_audio_decoded_.InMicroseconds());
}
private:
// Called by |audio_decoder_| to deliver each frame of decoded audio.
void OnDecodedFrame(bool should_be_continuous,
scoped_ptr<AudioBus> audio_bus,
bool is_continuous) {
DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
// A NULL |audio_bus| indicates a decode error, which we don't expect.
ASSERT_FALSE(!audio_bus);
// Did the decoder detect whether frames were dropped?
EXPECT_EQ(should_be_continuous, is_continuous);
// Does the audio data seem to be intact? For Opus, we have to ignore the
// first frame seen at the start (and immediately after dropped packet
// recovery) because it introduces a tiny, significant delay.
bool examine_signal = true;
if (GetParam().codec == transport::kOpus) {
examine_signal = seen_a_decoded_frame_ && should_be_continuous;
seen_a_decoded_frame_ = true;
}
if (examine_signal) {
for (int ch = 0; ch < audio_bus->channels(); ++ch) {
EXPECT_NEAR(
TestAudioBusFactory::kMiddleANoteFreq * 2 * audio_bus->frames() /
GetParam().sampling_rate,
CountZeroCrossings(audio_bus->channel(ch), audio_bus->frames()),
1);
}
}
// Signal the main test thread that more audio was decoded.
base::AutoLock auto_lock(lock_);
total_audio_decoded_ += base::TimeDelta::FromSeconds(1) *
audio_bus->frames() / GetParam().sampling_rate;
cond_.Signal();
}
const scoped_refptr<StandaloneCastEnvironment> cast_environment_;
scoped_ptr<AudioDecoder> audio_decoder_;
scoped_ptr<TestAudioBusFactory> audio_bus_factory_;
uint32 last_frame_id_;
bool seen_a_decoded_frame_;
scoped_ptr<uint8[]> opus_encoder_memory_;
base::Lock lock_;
base::ConditionVariable cond_;
base::TimeDelta total_audio_feed_in_;
base::TimeDelta total_audio_decoded_;
DISALLOW_COPY_AND_ASSIGN(AudioDecoderTest);
};
TEST_P(AudioDecoderTest, DecodesFramesWithSameDuration) {
const base::TimeDelta kTenMilliseconds =
base::TimeDelta::FromMilliseconds(10);
const int kNumFrames = 10;
for (int i = 0; i < kNumFrames; ++i)
FeedMoreAudio(kTenMilliseconds, 0);
WaitForAllAudioToBeDecoded();
}
TEST_P(AudioDecoderTest, DecodesFramesWithVaryingDuration) {
// These are the set of frame durations supported by the Opus encoder.
const int kFrameDurationMs[] = { 5, 10, 20, 40, 60 };
const int kNumFrames = 10;
for (size_t i = 0; i < arraysize(kFrameDurationMs); ++i)
for (int j = 0; j < kNumFrames; ++j)
FeedMoreAudio(base::TimeDelta::FromMilliseconds(kFrameDurationMs[i]), 0);
WaitForAllAudioToBeDecoded();
}
TEST_P(AudioDecoderTest, RecoversFromDroppedFrames) {
const base::TimeDelta kTenMilliseconds =
base::TimeDelta::FromMilliseconds(10);
const int kNumFrames = 100;
int next_drop_at = 3;
int next_num_dropped = 1;
for (int i = 0; i < kNumFrames; ++i) {
if (i == next_drop_at) {
const int num_dropped = next_num_dropped++;
next_drop_at *= 2;
i += num_dropped;
FeedMoreAudio(kTenMilliseconds, num_dropped);
} else {
FeedMoreAudio(kTenMilliseconds, 0);
}
}
WaitForAllAudioToBeDecoded();
}
INSTANTIATE_TEST_CASE_P(AudioDecoderTestScenarios,
AudioDecoderTest,
::testing::Values(
TestScenario(transport::kPcm16, 1, 8000),
TestScenario(transport::kPcm16, 2, 48000),
TestScenario(transport::kOpus, 1, 8000),
TestScenario(transport::kOpus, 2, 48000)));
} // namespace cast
} // namespace media