webrtc_m130/webrtc/modules/audio_coding/neteq/neteq_impl_unittest.cc

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/*
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "webrtc/modules/audio_coding/neteq/interface/neteq.h"
#include "webrtc/modules/audio_coding/neteq/neteq_impl.h"
#include "testing/gmock/include/gmock/gmock.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "webrtc/modules/audio_coding/neteq/accelerate.h"
#include "webrtc/modules/audio_coding/neteq/expand.h"
#include "webrtc/modules/audio_coding/neteq/mock/mock_audio_decoder.h"
#include "webrtc/modules/audio_coding/neteq/mock/mock_buffer_level_filter.h"
#include "webrtc/modules/audio_coding/neteq/mock/mock_decoder_database.h"
#include "webrtc/modules/audio_coding/neteq/mock/mock_delay_manager.h"
#include "webrtc/modules/audio_coding/neteq/mock/mock_delay_peak_detector.h"
#include "webrtc/modules/audio_coding/neteq/mock/mock_dtmf_buffer.h"
#include "webrtc/modules/audio_coding/neteq/mock/mock_dtmf_tone_generator.h"
#include "webrtc/modules/audio_coding/neteq/mock/mock_packet_buffer.h"
#include "webrtc/modules/audio_coding/neteq/mock/mock_payload_splitter.h"
#include "webrtc/modules/audio_coding/neteq/preemptive_expand.h"
#include "webrtc/modules/audio_coding/neteq/sync_buffer.h"
#include "webrtc/modules/audio_coding/neteq/timestamp_scaler.h"
using ::testing::Return;
using ::testing::ReturnNull;
using ::testing::_;
using ::testing::SetArgPointee;
using ::testing::InSequence;
using ::testing::Invoke;
using ::testing::WithArg;
namespace webrtc {
// This function is called when inserting a packet list into the mock packet
// buffer. The purpose is to delete all inserted packets properly, to avoid
// memory leaks in the test.
int DeletePacketsAndReturnOk(PacketList* packet_list) {
PacketBuffer::DeleteAllPackets(packet_list);
return PacketBuffer::kOK;
}
class NetEqImplTest : public ::testing::Test {
protected:
NetEqImplTest()
: neteq_(NULL),
config_(),
mock_buffer_level_filter_(NULL),
buffer_level_filter_(NULL),
use_mock_buffer_level_filter_(true),
mock_decoder_database_(NULL),
decoder_database_(NULL),
use_mock_decoder_database_(true),
mock_delay_peak_detector_(NULL),
delay_peak_detector_(NULL),
use_mock_delay_peak_detector_(true),
mock_delay_manager_(NULL),
delay_manager_(NULL),
use_mock_delay_manager_(true),
mock_dtmf_buffer_(NULL),
dtmf_buffer_(NULL),
use_mock_dtmf_buffer_(true),
mock_dtmf_tone_generator_(NULL),
dtmf_tone_generator_(NULL),
use_mock_dtmf_tone_generator_(true),
mock_packet_buffer_(NULL),
packet_buffer_(NULL),
use_mock_packet_buffer_(true),
mock_payload_splitter_(NULL),
payload_splitter_(NULL),
use_mock_payload_splitter_(true),
timestamp_scaler_(NULL) {
config_.sample_rate_hz = 8000;
}
void CreateInstance() {
if (use_mock_buffer_level_filter_) {
mock_buffer_level_filter_ = new MockBufferLevelFilter;
buffer_level_filter_ = mock_buffer_level_filter_;
} else {
buffer_level_filter_ = new BufferLevelFilter;
}
if (use_mock_decoder_database_) {
mock_decoder_database_ = new MockDecoderDatabase;
EXPECT_CALL(*mock_decoder_database_, GetActiveCngDecoder())
.WillOnce(ReturnNull());
decoder_database_ = mock_decoder_database_;
} else {
decoder_database_ = new DecoderDatabase;
}
if (use_mock_delay_peak_detector_) {
mock_delay_peak_detector_ = new MockDelayPeakDetector;
EXPECT_CALL(*mock_delay_peak_detector_, Reset()).Times(1);
delay_peak_detector_ = mock_delay_peak_detector_;
} else {
delay_peak_detector_ = new DelayPeakDetector;
}
if (use_mock_delay_manager_) {
mock_delay_manager_ = new MockDelayManager(config_.max_packets_in_buffer,
delay_peak_detector_);
EXPECT_CALL(*mock_delay_manager_, set_streaming_mode(false)).Times(1);
delay_manager_ = mock_delay_manager_;
} else {
delay_manager_ =
new DelayManager(config_.max_packets_in_buffer, delay_peak_detector_);
}
if (use_mock_dtmf_buffer_) {
mock_dtmf_buffer_ = new MockDtmfBuffer(config_.sample_rate_hz);
dtmf_buffer_ = mock_dtmf_buffer_;
} else {
dtmf_buffer_ = new DtmfBuffer(config_.sample_rate_hz);
}
if (use_mock_dtmf_tone_generator_) {
mock_dtmf_tone_generator_ = new MockDtmfToneGenerator;
dtmf_tone_generator_ = mock_dtmf_tone_generator_;
} else {
dtmf_tone_generator_ = new DtmfToneGenerator;
}
if (use_mock_packet_buffer_) {
mock_packet_buffer_ = new MockPacketBuffer(config_.max_packets_in_buffer);
packet_buffer_ = mock_packet_buffer_;
} else {
packet_buffer_ = new PacketBuffer(config_.max_packets_in_buffer);
}
if (use_mock_payload_splitter_) {
mock_payload_splitter_ = new MockPayloadSplitter;
payload_splitter_ = mock_payload_splitter_;
} else {
payload_splitter_ = new PayloadSplitter;
}
timestamp_scaler_ = new TimestampScaler(*decoder_database_);
AccelerateFactory* accelerate_factory = new AccelerateFactory;
ExpandFactory* expand_factory = new ExpandFactory;
PreemptiveExpandFactory* preemptive_expand_factory =
new PreemptiveExpandFactory;
neteq_ = new NetEqImpl(config_,
buffer_level_filter_,
decoder_database_,
delay_manager_,
delay_peak_detector_,
dtmf_buffer_,
dtmf_tone_generator_,
packet_buffer_,
payload_splitter_,
timestamp_scaler_,
accelerate_factory,
expand_factory,
preemptive_expand_factory);
ASSERT_TRUE(neteq_ != NULL);
}
void UseNoMocks() {
ASSERT_TRUE(neteq_ == NULL) << "Must call UseNoMocks before CreateInstance";
use_mock_buffer_level_filter_ = false;
use_mock_decoder_database_ = false;
use_mock_delay_peak_detector_ = false;
use_mock_delay_manager_ = false;
use_mock_dtmf_buffer_ = false;
use_mock_dtmf_tone_generator_ = false;
use_mock_packet_buffer_ = false;
use_mock_payload_splitter_ = false;
}
virtual ~NetEqImplTest() {
if (use_mock_buffer_level_filter_) {
EXPECT_CALL(*mock_buffer_level_filter_, Die()).Times(1);
}
if (use_mock_decoder_database_) {
EXPECT_CALL(*mock_decoder_database_, Die()).Times(1);
}
if (use_mock_delay_manager_) {
EXPECT_CALL(*mock_delay_manager_, Die()).Times(1);
}
if (use_mock_delay_peak_detector_) {
EXPECT_CALL(*mock_delay_peak_detector_, Die()).Times(1);
}
if (use_mock_dtmf_buffer_) {
EXPECT_CALL(*mock_dtmf_buffer_, Die()).Times(1);
}
if (use_mock_dtmf_tone_generator_) {
EXPECT_CALL(*mock_dtmf_tone_generator_, Die()).Times(1);
}
if (use_mock_packet_buffer_) {
EXPECT_CALL(*mock_packet_buffer_, Die()).Times(1);
}
delete neteq_;
}
NetEqImpl* neteq_;
NetEq::Config config_;
MockBufferLevelFilter* mock_buffer_level_filter_;
BufferLevelFilter* buffer_level_filter_;
bool use_mock_buffer_level_filter_;
MockDecoderDatabase* mock_decoder_database_;
DecoderDatabase* decoder_database_;
bool use_mock_decoder_database_;
MockDelayPeakDetector* mock_delay_peak_detector_;
DelayPeakDetector* delay_peak_detector_;
bool use_mock_delay_peak_detector_;
MockDelayManager* mock_delay_manager_;
DelayManager* delay_manager_;
bool use_mock_delay_manager_;
MockDtmfBuffer* mock_dtmf_buffer_;
DtmfBuffer* dtmf_buffer_;
bool use_mock_dtmf_buffer_;
MockDtmfToneGenerator* mock_dtmf_tone_generator_;
DtmfToneGenerator* dtmf_tone_generator_;
bool use_mock_dtmf_tone_generator_;
MockPacketBuffer* mock_packet_buffer_;
PacketBuffer* packet_buffer_;
bool use_mock_packet_buffer_;
MockPayloadSplitter* mock_payload_splitter_;
PayloadSplitter* payload_splitter_;
bool use_mock_payload_splitter_;
TimestampScaler* timestamp_scaler_;
};
// This tests the interface class NetEq.
// TODO(hlundin): Move to separate file?
TEST(NetEq, CreateAndDestroy) {
NetEq::Config config;
NetEq* neteq = NetEq::Create(config);
delete neteq;
}
TEST_F(NetEqImplTest, RegisterPayloadType) {
CreateInstance();
uint8_t rtp_payload_type = 0;
NetEqDecoder codec_type = kDecoderPCMu;
EXPECT_CALL(*mock_decoder_database_,
RegisterPayload(rtp_payload_type, codec_type));
neteq_->RegisterPayloadType(codec_type, rtp_payload_type);
}
TEST_F(NetEqImplTest, RemovePayloadType) {
CreateInstance();
uint8_t rtp_payload_type = 0;
EXPECT_CALL(*mock_decoder_database_, Remove(rtp_payload_type))
.WillOnce(Return(DecoderDatabase::kDecoderNotFound));
// Check that kFail is returned when database returns kDecoderNotFound.
EXPECT_EQ(NetEq::kFail, neteq_->RemovePayloadType(rtp_payload_type));
}
TEST_F(NetEqImplTest, InsertPacket) {
CreateInstance();
const int kPayloadLength = 100;
const uint8_t kPayloadType = 0;
const uint16_t kFirstSequenceNumber = 0x1234;
const uint32_t kFirstTimestamp = 0x12345678;
const uint32_t kSsrc = 0x87654321;
const uint32_t kFirstReceiveTime = 17;
uint8_t payload[kPayloadLength] = {0};
WebRtcRTPHeader rtp_header;
rtp_header.header.payloadType = kPayloadType;
rtp_header.header.sequenceNumber = kFirstSequenceNumber;
rtp_header.header.timestamp = kFirstTimestamp;
rtp_header.header.ssrc = kSsrc;
// Create a mock decoder object.
MockAudioDecoder mock_decoder;
// BWE update function called with first packet.
EXPECT_CALL(mock_decoder, IncomingPacket(_,
kPayloadLength,
kFirstSequenceNumber,
kFirstTimestamp,
kFirstReceiveTime));
// BWE update function called with second packet.
EXPECT_CALL(mock_decoder, IncomingPacket(_,
kPayloadLength,
kFirstSequenceNumber + 1,
kFirstTimestamp + 160,
kFirstReceiveTime + 155));
EXPECT_CALL(mock_decoder, Die()).Times(1); // Called when deleted.
// Expectations for decoder database.
EXPECT_CALL(*mock_decoder_database_, IsRed(kPayloadType))
.WillRepeatedly(Return(false)); // This is not RED.
EXPECT_CALL(*mock_decoder_database_, CheckPayloadTypes(_))
.Times(2)
.WillRepeatedly(Return(DecoderDatabase::kOK)); // Payload type is valid.
EXPECT_CALL(*mock_decoder_database_, IsDtmf(kPayloadType))
.WillRepeatedly(Return(false)); // This is not DTMF.
EXPECT_CALL(*mock_decoder_database_, GetDecoder(kPayloadType))
Update sampling rate and number of channels of NetEq4 if decoder is changed. We encounter a sample-underrun if NetEq is initialized with a sampling rate fs =16000 and receive Opus packets with frame-size less than 5 ms. The reason is as follows. Let say NetEq buffer has 4 packets of Opus each of size 2.5ms this means that internally timestamp of packets incremented by 80 (internally Opus treated as 32 kHz codec). Given the initial sampling rate of NetEq, at the first time that it wants to fetch packets, it targets to fetch 160 samples. Therefore, it will only extracts 2 packets. Decoding these packets give us exactly 160 samples (5 ms at 32 kHz), however, upon decoding the first packet the internal sampling rate will be updated to 32 kHz. So it is expected that sync buffer to deliver 320 samples while it does only have 160 samples (or maybe few more as it starts with some zeros). And we encounter and under-run. Even if we ignore the under-run "assert(sync_buffer_->FutureLength() >= expand_->overlap_length())" (neteq_impl.cc::811) is trigered. I'm not sure what happens if we remove this assert perhaps NetEq will work fine in subsequent calls. However the first under-run is blocking ACM2 test to pass. Here I have a solution to update sample rate as soon as a packet is inserted, if required. It not a very efficient approach as we do the same reset in NetEqImpl::Decode(). It is a bit tricky to reproduce this because the TOT ACM tests do not run ACM2. In https://webrtc-codereview.appspot.com/2192005/ I have a patch to run both ACMs. To reproduce the problem, one can patch that CL and run $ out/Debug/modules_tests --gtest_filter=AudioCodingModuleTest.TestOpus Note that we would not encounter any problem if NetEq4 is initiated with 32000 Hz sampling rate. You can test this by setting |kNeteqInitSampleRateHz| to 32000 in webrtc/modules/audio_coding/main/acm2/acm_receiver.cc BUG= R=andrew@webrtc.org, henrik.lundin@webrtc.org, kjellander@webrtc.org Review URL: https://webrtc-codereview.appspot.com/2306004 git-svn-id: http://webrtc.googlecode.com/svn/trunk@4896 4adac7df-926f-26a2-2b94-8c16560cd09d
2013-10-01 22:01:09 +00:00
.Times(3)
.WillRepeatedly(Return(&mock_decoder));
EXPECT_CALL(*mock_decoder_database_, IsComfortNoise(kPayloadType))
.WillRepeatedly(Return(false)); // This is not CNG.
DecoderDatabase::DecoderInfo info;
info.codec_type = kDecoderPCMu;
EXPECT_CALL(*mock_decoder_database_, GetDecoderInfo(kPayloadType))
.WillRepeatedly(Return(&info));
// Expectations for packet buffer.
EXPECT_CALL(*mock_packet_buffer_, NumPacketsInBuffer())
.WillOnce(Return(0)) // First packet.
.WillOnce(Return(1)) // Second packet.
.WillOnce(Return(2)); // Second packet, checking after it was inserted.
EXPECT_CALL(*mock_packet_buffer_, Empty())
.WillOnce(Return(false)); // Called once after first packet is inserted.
EXPECT_CALL(*mock_packet_buffer_, Flush())
.Times(1);
EXPECT_CALL(*mock_packet_buffer_, InsertPacketList(_, _, _, _))
.Times(2)
.WillRepeatedly(DoAll(SetArgPointee<2>(kPayloadType),
WithArg<0>(Invoke(DeletePacketsAndReturnOk))));
// SetArgPointee<2>(kPayloadType) means that the third argument (zero-based
// index) is a pointer, and the variable pointed to is set to kPayloadType.
// Also invoke the function DeletePacketsAndReturnOk to properly delete all
// packets in the list (to avoid memory leaks in the test).
EXPECT_CALL(*mock_packet_buffer_, NextRtpHeader())
Update sampling rate and number of channels of NetEq4 if decoder is changed. We encounter a sample-underrun if NetEq is initialized with a sampling rate fs =16000 and receive Opus packets with frame-size less than 5 ms. The reason is as follows. Let say NetEq buffer has 4 packets of Opus each of size 2.5ms this means that internally timestamp of packets incremented by 80 (internally Opus treated as 32 kHz codec). Given the initial sampling rate of NetEq, at the first time that it wants to fetch packets, it targets to fetch 160 samples. Therefore, it will only extracts 2 packets. Decoding these packets give us exactly 160 samples (5 ms at 32 kHz), however, upon decoding the first packet the internal sampling rate will be updated to 32 kHz. So it is expected that sync buffer to deliver 320 samples while it does only have 160 samples (or maybe few more as it starts with some zeros). And we encounter and under-run. Even if we ignore the under-run "assert(sync_buffer_->FutureLength() >= expand_->overlap_length())" (neteq_impl.cc::811) is trigered. I'm not sure what happens if we remove this assert perhaps NetEq will work fine in subsequent calls. However the first under-run is blocking ACM2 test to pass. Here I have a solution to update sample rate as soon as a packet is inserted, if required. It not a very efficient approach as we do the same reset in NetEqImpl::Decode(). It is a bit tricky to reproduce this because the TOT ACM tests do not run ACM2. In https://webrtc-codereview.appspot.com/2192005/ I have a patch to run both ACMs. To reproduce the problem, one can patch that CL and run $ out/Debug/modules_tests --gtest_filter=AudioCodingModuleTest.TestOpus Note that we would not encounter any problem if NetEq4 is initiated with 32000 Hz sampling rate. You can test this by setting |kNeteqInitSampleRateHz| to 32000 in webrtc/modules/audio_coding/main/acm2/acm_receiver.cc BUG= R=andrew@webrtc.org, henrik.lundin@webrtc.org, kjellander@webrtc.org Review URL: https://webrtc-codereview.appspot.com/2306004 git-svn-id: http://webrtc.googlecode.com/svn/trunk@4896 4adac7df-926f-26a2-2b94-8c16560cd09d
2013-10-01 22:01:09 +00:00
.Times(1)
.WillOnce(Return(&rtp_header.header));
// Expectations for DTMF buffer.
EXPECT_CALL(*mock_dtmf_buffer_, Flush())
.Times(1);
// Expectations for delay manager.
{
// All expectations within this block must be called in this specific order.
InSequence sequence; // Dummy variable.
// Expectations when the first packet is inserted.
EXPECT_CALL(*mock_delay_manager_, LastDecoderType(kDecoderPCMu))
.Times(1);
EXPECT_CALL(*mock_delay_manager_, last_pack_cng_or_dtmf())
.Times(2)
.WillRepeatedly(Return(-1));
EXPECT_CALL(*mock_delay_manager_, set_last_pack_cng_or_dtmf(0))
.Times(1);
EXPECT_CALL(*mock_delay_manager_, ResetPacketIatCount()).Times(1);
// Expectations when the second packet is inserted. Slightly different.
EXPECT_CALL(*mock_delay_manager_, LastDecoderType(kDecoderPCMu))
.Times(1);
EXPECT_CALL(*mock_delay_manager_, last_pack_cng_or_dtmf())
.WillOnce(Return(0));
EXPECT_CALL(*mock_delay_manager_, SetPacketAudioLength(30))
.WillOnce(Return(0));
}
// Expectations for payload splitter.
EXPECT_CALL(*mock_payload_splitter_, SplitAudio(_, _))
.Times(2)
.WillRepeatedly(Return(PayloadSplitter::kOK));
// Insert first packet.
neteq_->InsertPacket(rtp_header, payload, kPayloadLength, kFirstReceiveTime);
// Insert second packet.
rtp_header.header.timestamp += 160;
rtp_header.header.sequenceNumber += 1;
neteq_->InsertPacket(rtp_header, payload, kPayloadLength,
kFirstReceiveTime + 155);
}
TEST_F(NetEqImplTest, InsertPacketsUntilBufferIsFull) {
UseNoMocks();
CreateInstance();
const int kPayloadLengthSamples = 80;
const size_t kPayloadLengthBytes = 2 * kPayloadLengthSamples; // PCM 16-bit.
const uint8_t kPayloadType = 17; // Just an arbitrary number.
const uint32_t kReceiveTime = 17; // Value doesn't matter for this test.
uint8_t payload[kPayloadLengthBytes] = {0};
WebRtcRTPHeader rtp_header;
rtp_header.header.payloadType = kPayloadType;
rtp_header.header.sequenceNumber = 0x1234;
rtp_header.header.timestamp = 0x12345678;
rtp_header.header.ssrc = 0x87654321;
EXPECT_EQ(NetEq::kOK,
neteq_->RegisterPayloadType(kDecoderPCM16B, kPayloadType));
// Insert packets. The buffer should not flush.
for (int i = 1; i <= config_.max_packets_in_buffer; ++i) {
EXPECT_EQ(NetEq::kOK,
neteq_->InsertPacket(
rtp_header, payload, kPayloadLengthBytes, kReceiveTime));
rtp_header.header.timestamp += kPayloadLengthSamples;
rtp_header.header.sequenceNumber += 1;
EXPECT_EQ(i, packet_buffer_->NumPacketsInBuffer());
}
// Insert one more packet and make sure the buffer got flushed. That is, it
// should only hold one single packet.
EXPECT_EQ(NetEq::kOK,
neteq_->InsertPacket(
rtp_header, payload, kPayloadLengthBytes, kReceiveTime));
EXPECT_EQ(1, packet_buffer_->NumPacketsInBuffer());
const RTPHeader* test_header = packet_buffer_->NextRtpHeader();
EXPECT_EQ(rtp_header.header.timestamp, test_header->timestamp);
EXPECT_EQ(rtp_header.header.sequenceNumber, test_header->sequenceNumber);
}
// This test verifies that timestamps propagate from the incoming packets
// through to the sync buffer and to the playout timestamp.
TEST_F(NetEqImplTest, VerifyTimestampPropagation) {
UseNoMocks();
CreateInstance();
const uint8_t kPayloadType = 17; // Just an arbitrary number.
const uint32_t kReceiveTime = 17; // Value doesn't matter for this test.
const int kSampleRateHz = 8000;
const int kPayloadLengthSamples = 10 * kSampleRateHz / 1000; // 10 ms.
const size_t kPayloadLengthBytes = kPayloadLengthSamples;
uint8_t payload[kPayloadLengthBytes] = {0};
WebRtcRTPHeader rtp_header;
rtp_header.header.payloadType = kPayloadType;
rtp_header.header.sequenceNumber = 0x1234;
rtp_header.header.timestamp = 0x12345678;
rtp_header.header.ssrc = 0x87654321;
// This is a dummy decoder that produces as many output samples as the input
// has bytes. The output is an increasing series, starting at 1 for the first
// sample, and then increasing by 1 for each sample.
class CountingSamplesDecoder : public AudioDecoder {
public:
explicit CountingSamplesDecoder(enum NetEqDecoder type)
: AudioDecoder(type), next_value_(1) {}
// Produce as many samples as input bytes (|encoded_len|).
virtual int Decode(const uint8_t* encoded,
size_t encoded_len,
int16_t* decoded,
SpeechType* speech_type) {
for (size_t i = 0; i < encoded_len; ++i) {
decoded[i] = next_value_++;
}
*speech_type = kSpeech;
return encoded_len;
}
virtual int Init() {
next_value_ = 1;
return 0;
}
uint16_t next_value() const { return next_value_; }
private:
int16_t next_value_;
} decoder_(kDecoderPCM16B);
EXPECT_EQ(NetEq::kOK,
neteq_->RegisterExternalDecoder(
&decoder_, kDecoderPCM16B, kPayloadType));
// Insert one packet.
EXPECT_EQ(NetEq::kOK,
neteq_->InsertPacket(
rtp_header, payload, kPayloadLengthBytes, kReceiveTime));
// Pull audio once.
const int kMaxOutputSize = 10 * kSampleRateHz / 1000;
int16_t output[kMaxOutputSize];
int samples_per_channel;
int num_channels;
NetEqOutputType type;
EXPECT_EQ(
NetEq::kOK,
neteq_->GetAudio(
kMaxOutputSize, output, &samples_per_channel, &num_channels, &type));
ASSERT_EQ(kMaxOutputSize, samples_per_channel);
EXPECT_EQ(1, num_channels);
EXPECT_EQ(kOutputNormal, type);
// Start with a simple check that the fake decoder is behaving as expected.
EXPECT_EQ(kPayloadLengthSamples, decoder_.next_value() - 1);
// The value of the last of the output samples is the same as the number of
// samples played from the decoded packet. Thus, this number + the RTP
// timestamp should match the playout timestamp.
uint32_t timestamp = 0;
EXPECT_TRUE(neteq_->GetPlayoutTimestamp(&timestamp));
EXPECT_EQ(rtp_header.header.timestamp + output[samples_per_channel - 1],
timestamp);
// Check the timestamp for the last value in the sync buffer. This should
// be one full frame length ahead of the RTP timestamp.
const SyncBuffer* sync_buffer = neteq_->sync_buffer_for_test();
ASSERT_TRUE(sync_buffer != NULL);
EXPECT_EQ(rtp_header.header.timestamp + kPayloadLengthSamples,
sync_buffer->end_timestamp());
// Check that the number of samples still to play from the sync buffer add
// up with what was already played out.
EXPECT_EQ(kPayloadLengthSamples - output[samples_per_channel - 1],
static_cast<int>(sync_buffer->FutureLength()));
}
} // namespace webrtc