blob: bfa12706fdb55faa4b78404d83cd2f0b9bbfb71e [file] [log] [blame]
// 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.
//
// This program benchmarks the theoretical throughput of the cast library.
// It runs using a fake clock, simulated network and fake codecs. This allows
// tests to run much faster than real time.
// To run the program, run:
// $ ./out/Release/cast_benchmarks | tee benchmarkoutput.asc
// This may take a while, when it is done, you can view the data with
// meshlab by running:
// $ meshlab benchmarkoutput.asc
// After starting meshlab, turn on Render->Show Axis. The red axis will
// represent bandwidth (in megabits) the blue axis will be packet drop
// (in percent) and the green axis will be latency (in milliseconds).
//
// This program can also be used for profiling. On linux it has
// built-in support for this. Simply set the environment variable
// PROFILE_FILE before running it, like so:
// $ export PROFILE_FILE=cast_benchmark.profile
// Then after running the program, you can view the profile with:
// $ pprof ./out/Release/cast_benchmarks $PROFILE_FILE --gv
#include <math.h>
#include <stdint.h>
#include <map>
#include <vector>
#include "base/at_exit.h"
#include "base/bind.h"
#include "base/bind_helpers.h"
#include "base/command_line.h"
#include "base/debug/profiler.h"
#include "base/stl_util.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/stringprintf.h"
#include "base/test/simple_test_tick_clock.h"
#include "base/threading/thread.h"
#include "base/time/tick_clock.h"
#include "media/base/audio_bus.h"
#include "media/base/video_frame.h"
#include "media/cast/cast_config.h"
#include "media/cast/cast_environment.h"
#include "media/cast/cast_receiver.h"
#include "media/cast/cast_sender.h"
#include "media/cast/logging/simple_event_subscriber.h"
#include "media/cast/net/cast_transport_config.h"
#include "media/cast/net/cast_transport_defines.h"
#include "media/cast/net/cast_transport_sender.h"
#include "media/cast/net/cast_transport_sender_impl.h"
#include "media/cast/test/fake_single_thread_task_runner.h"
#include "media/cast/test/loopback_transport.h"
#include "media/cast/test/skewed_single_thread_task_runner.h"
#include "media/cast/test/skewed_tick_clock.h"
#include "media/cast/test/utility/audio_utility.h"
#include "media/cast/test/utility/default_config.h"
#include "media/cast/test/utility/test_util.h"
#include "media/cast/test/utility/udp_proxy.h"
#include "media/cast/test/utility/video_utility.h"
#include "testing/gtest/include/gtest/gtest.h"
namespace media {
namespace cast {
namespace {
static const int64 kStartMillisecond = INT64_C(1245);
static const int kAudioChannels = 2;
static const int kVideoHdWidth = 1280;
static const int kVideoHdHeight = 720;
static const int kTargetPlayoutDelayMs = 300;
// The tests are commonly implemented with |kFrameTimerMs| RunTask function;
// a normal video is 30 fps hence the 33 ms between frames.
static const int kFrameTimerMs = 33;
void UpdateCastTransportStatus(CastTransportStatus status) {
bool result = (status == TRANSPORT_AUDIO_INITIALIZED ||
status == TRANSPORT_VIDEO_INITIALIZED);
EXPECT_TRUE(result);
}
void AudioInitializationStatus(CastInitializationStatus status) {
EXPECT_EQ(STATUS_AUDIO_INITIALIZED, status);
}
void VideoInitializationStatus(CastInitializationStatus status) {
EXPECT_EQ(STATUS_VIDEO_INITIALIZED, status);
}
void IgnoreRawEvents(const std::vector<PacketEvent>& packet_events,
const std::vector<FrameEvent>& frame_events) {
}
} // namespace
// Wraps a CastTransportSender and records some statistics about
// the data that goes through it.
class CastTransportSenderWrapper : public CastTransportSender {
public:
// Takes ownership of |transport|.
void Init(CastTransportSender* transport,
uint64* encoded_video_bytes,
uint64* encoded_audio_bytes) {
transport_.reset(transport);
encoded_video_bytes_ = encoded_video_bytes;
encoded_audio_bytes_ = encoded_audio_bytes;
}
void InitializeAudio(const CastTransportRtpConfig& config,
const RtcpCastMessageCallback& cast_message_cb,
const RtcpRttCallback& rtt_cb) override {
audio_ssrc_ = config.ssrc;
transport_->InitializeAudio(config, cast_message_cb, rtt_cb);
}
void InitializeVideo(const CastTransportRtpConfig& config,
const RtcpCastMessageCallback& cast_message_cb,
const RtcpRttCallback& rtt_cb) override {
video_ssrc_ = config.ssrc;
transport_->InitializeVideo(config, cast_message_cb, rtt_cb);
}
void InsertFrame(uint32 ssrc, const EncodedFrame& frame) override {
if (ssrc == audio_ssrc_) {
*encoded_audio_bytes_ += frame.data.size();
} else if (ssrc == video_ssrc_) {
*encoded_video_bytes_ += frame.data.size();
}
transport_->InsertFrame(ssrc, frame);
}
void SendSenderReport(uint32 ssrc,
base::TimeTicks current_time,
uint32 current_time_as_rtp_timestamp) override {
transport_->SendSenderReport(ssrc,
current_time,
current_time_as_rtp_timestamp);
}
void CancelSendingFrames(uint32 ssrc,
const std::vector<uint32>& frame_ids) override {
transport_->CancelSendingFrames(ssrc, frame_ids);
}
void ResendFrameForKickstart(uint32 ssrc, uint32 frame_id) override {
transport_->ResendFrameForKickstart(ssrc, frame_id);
}
PacketReceiverCallback PacketReceiverForTesting() override {
return transport_->PacketReceiverForTesting();
}
private:
scoped_ptr<CastTransportSender> transport_;
uint32 audio_ssrc_, video_ssrc_;
uint64* encoded_video_bytes_;
uint64* encoded_audio_bytes_;
};
struct MeasuringPoint {
MeasuringPoint(double bitrate_, double latency_, double percent_packet_drop_)
: bitrate(bitrate_),
latency(latency_),
percent_packet_drop(percent_packet_drop_) {}
bool operator<=(const MeasuringPoint& other) const {
return bitrate >= other.bitrate && latency <= other.latency &&
percent_packet_drop <= other.percent_packet_drop;
}
bool operator>=(const MeasuringPoint& other) const {
return bitrate <= other.bitrate && latency >= other.latency &&
percent_packet_drop >= other.percent_packet_drop;
}
std::string AsString() const {
return base::StringPrintf(
"%f Mbit/s %f ms %f %% ", bitrate, latency, percent_packet_drop);
}
double bitrate;
double latency;
double percent_packet_drop;
};
class RunOneBenchmark {
public:
RunOneBenchmark()
: start_time_(),
task_runner_(new test::FakeSingleThreadTaskRunner(&testing_clock_)),
testing_clock_sender_(new test::SkewedTickClock(&testing_clock_)),
task_runner_sender_(
new test::SkewedSingleThreadTaskRunner(task_runner_)),
testing_clock_receiver_(new test::SkewedTickClock(&testing_clock_)),
task_runner_receiver_(
new test::SkewedSingleThreadTaskRunner(task_runner_)),
cast_environment_sender_(new CastEnvironment(
scoped_ptr<base::TickClock>(testing_clock_sender_).Pass(),
task_runner_sender_,
task_runner_sender_,
task_runner_sender_)),
cast_environment_receiver_(new CastEnvironment(
scoped_ptr<base::TickClock>(testing_clock_receiver_).Pass(),
task_runner_receiver_,
task_runner_receiver_,
task_runner_receiver_)),
receiver_to_sender_(cast_environment_receiver_),
sender_to_receiver_(cast_environment_sender_),
video_bytes_encoded_(0),
audio_bytes_encoded_(0),
frames_sent_(0) {
testing_clock_.Advance(
base::TimeDelta::FromMilliseconds(kStartMillisecond));
}
void Configure(Codec video_codec,
Codec audio_codec,
int audio_sampling_frequency,
int max_number_of_video_buffers_used) {
audio_sender_config_.ssrc = 1;
audio_sender_config_.incoming_feedback_ssrc = 2;
audio_sender_config_.max_playout_delay =
base::TimeDelta::FromMilliseconds(kTargetPlayoutDelayMs);
audio_sender_config_.rtp_payload_type = 96;
audio_sender_config_.use_external_encoder = false;
audio_sender_config_.frequency = audio_sampling_frequency;
audio_sender_config_.channels = kAudioChannels;
audio_sender_config_.bitrate = kDefaultAudioEncoderBitrate;
audio_sender_config_.codec = audio_codec;
audio_receiver_config_.feedback_ssrc =
audio_sender_config_.incoming_feedback_ssrc;
audio_receiver_config_.incoming_ssrc = audio_sender_config_.ssrc;
audio_receiver_config_.rtp_payload_type =
audio_sender_config_.rtp_payload_type;
audio_receiver_config_.frequency = audio_sender_config_.frequency;
audio_receiver_config_.channels = kAudioChannels;
audio_receiver_config_.max_frame_rate = 100;
audio_receiver_config_.codec = audio_sender_config_.codec;
audio_receiver_config_.rtp_max_delay_ms = kTargetPlayoutDelayMs;
video_sender_config_.ssrc = 3;
video_sender_config_.incoming_feedback_ssrc = 4;
video_sender_config_.max_playout_delay =
base::TimeDelta::FromMilliseconds(kTargetPlayoutDelayMs);
video_sender_config_.rtp_payload_type = 97;
video_sender_config_.use_external_encoder = false;
video_sender_config_.width = kVideoHdWidth;
video_sender_config_.height = kVideoHdHeight;
#if 0
video_sender_config_.max_bitrate = 10000000; // 10Mbit max
video_sender_config_.min_bitrate = 1000000; // 1Mbit min
video_sender_config_.start_bitrate = 1000000; // 1Mbit start
#else
video_sender_config_.max_bitrate = 4000000; // 4Mbit all the time
video_sender_config_.min_bitrate = 4000000;
video_sender_config_.start_bitrate = 4000000;
#endif
video_sender_config_.max_qp = 56;
video_sender_config_.min_qp = 4;
video_sender_config_.max_frame_rate = 30;
video_sender_config_.max_number_of_video_buffers_used =
max_number_of_video_buffers_used;
video_sender_config_.codec = video_codec;
video_receiver_config_.feedback_ssrc =
video_sender_config_.incoming_feedback_ssrc;
video_receiver_config_.incoming_ssrc = video_sender_config_.ssrc;
video_receiver_config_.rtp_payload_type =
video_sender_config_.rtp_payload_type;
video_receiver_config_.codec = video_sender_config_.codec;
video_receiver_config_.frequency = kVideoFrequency;
video_receiver_config_.channels = 1;
video_receiver_config_.max_frame_rate = 100;
video_receiver_config_.rtp_max_delay_ms = kTargetPlayoutDelayMs;
}
void SetSenderClockSkew(double skew, base::TimeDelta offset) {
testing_clock_sender_->SetSkew(skew, offset);
task_runner_sender_->SetSkew(1.0 / skew);
}
void SetReceiverClockSkew(double skew, base::TimeDelta offset) {
testing_clock_receiver_->SetSkew(skew, offset);
task_runner_receiver_->SetSkew(1.0 / skew);
}
void Create(const MeasuringPoint& p) {
cast_receiver_ = CastReceiver::Create(cast_environment_receiver_,
audio_receiver_config_,
video_receiver_config_,
&receiver_to_sender_);
net::IPEndPoint dummy_endpoint;
transport_sender_.Init(
new CastTransportSenderImpl(
NULL,
testing_clock_sender_,
dummy_endpoint,
make_scoped_ptr(new base::DictionaryValue),
base::Bind(&UpdateCastTransportStatus),
base::Bind(&IgnoreRawEvents),
base::TimeDelta::FromSeconds(1),
task_runner_sender_,
&sender_to_receiver_),
&video_bytes_encoded_,
&audio_bytes_encoded_);
cast_sender_ =
CastSender::Create(cast_environment_sender_, &transport_sender_);
// Initializing audio and video senders.
cast_sender_->InitializeAudio(audio_sender_config_,
base::Bind(&AudioInitializationStatus));
cast_sender_->InitializeVideo(video_sender_config_,
base::Bind(&VideoInitializationStatus),
CreateDefaultVideoEncodeAcceleratorCallback(),
CreateDefaultVideoEncodeMemoryCallback());
receiver_to_sender_.Initialize(
CreateSimplePipe(p).Pass(),
transport_sender_.PacketReceiverForTesting(),
task_runner_, &testing_clock_);
sender_to_receiver_.Initialize(
CreateSimplePipe(p).Pass(), cast_receiver_->packet_receiver(),
task_runner_, &testing_clock_);
}
virtual ~RunOneBenchmark() {
cast_sender_.reset();
cast_receiver_.reset();
task_runner_->RunTasks();
}
void SendFakeVideoFrame() {
frames_sent_++;
cast_sender_->video_frame_input()->InsertRawVideoFrame(
media::VideoFrame::CreateBlackFrame(gfx::Size(2, 2)),
testing_clock_sender_->NowTicks());
}
void RunTasks(int ms) {
task_runner_->Sleep(base::TimeDelta::FromMilliseconds(ms));
}
void BasicPlayerGotVideoFrame(
const scoped_refptr<media::VideoFrame>& video_frame,
const base::TimeTicks& render_time,
bool continuous) {
video_ticks_.push_back(
std::make_pair(testing_clock_receiver_->NowTicks(), render_time));
cast_receiver_->RequestDecodedVideoFrame(base::Bind(
&RunOneBenchmark::BasicPlayerGotVideoFrame, base::Unretained(this)));
}
void BasicPlayerGotAudioFrame(scoped_ptr<AudioBus> audio_bus,
const base::TimeTicks& playout_time,
bool is_continuous) {
audio_ticks_.push_back(
std::make_pair(testing_clock_receiver_->NowTicks(), playout_time));
cast_receiver_->RequestDecodedAudioFrame(base::Bind(
&RunOneBenchmark::BasicPlayerGotAudioFrame, base::Unretained(this)));
}
void StartBasicPlayer() {
cast_receiver_->RequestDecodedVideoFrame(base::Bind(
&RunOneBenchmark::BasicPlayerGotVideoFrame, base::Unretained(this)));
cast_receiver_->RequestDecodedAudioFrame(base::Bind(
&RunOneBenchmark::BasicPlayerGotAudioFrame, base::Unretained(this)));
}
scoped_ptr<test::PacketPipe> CreateSimplePipe(const MeasuringPoint& p) {
scoped_ptr<test::PacketPipe> pipe = test::NewBuffer(65536, p.bitrate);
pipe->AppendToPipe(
test::NewRandomDrop(p.percent_packet_drop / 100.0).Pass());
pipe->AppendToPipe(test::NewConstantDelay(p.latency / 1000.0));
return pipe.Pass();
}
void Run(const MeasuringPoint& p) {
available_bitrate_ = p.bitrate;
Configure(
CODEC_VIDEO_FAKE, CODEC_AUDIO_PCM16, 32000, 1);
Create(p);
StartBasicPlayer();
for (int frame = 0; frame < 1000; frame++) {
SendFakeVideoFrame();
RunTasks(kFrameTimerMs);
}
RunTasks(100 * kFrameTimerMs); // Empty the pipeline.
VLOG(1) << "=============INPUTS============";
VLOG(1) << "Bitrate: " << p.bitrate << " mbit/s";
VLOG(1) << "Latency: " << p.latency << " ms";
VLOG(1) << "Packet drop drop: " << p.percent_packet_drop << "%";
VLOG(1) << "=============OUTPUTS============";
VLOG(1) << "Frames lost: " << frames_lost();
VLOG(1) << "Late frames: " << late_frames();
VLOG(1) << "Playout margin: " << frame_playout_buffer().AsString();
VLOG(1) << "Video bandwidth used: " << video_bandwidth() << " mbit/s ("
<< (video_bandwidth() * 100 / desired_video_bitrate()) << "%)";
VLOG(1) << "Good run: " << SimpleGood();
}
// Metrics
int frames_lost() const { return frames_sent_ - video_ticks_.size(); }
int late_frames() const {
int frames = 0;
// Ignore the first two seconds of video or so.
for (size_t i = 60; i < video_ticks_.size(); i++) {
if (video_ticks_[i].first > video_ticks_[i].second) {
frames++;
}
}
return frames;
}
test::MeanAndError frame_playout_buffer() const {
std::vector<double> values;
for (size_t i = 0; i < video_ticks_.size(); i++) {
values.push_back(
(video_ticks_[i].second - video_ticks_[i].first).InMillisecondsF());
}
return test::MeanAndError(values);
}
// Mbits per second
double video_bandwidth() const {
double seconds = (kFrameTimerMs * frames_sent_ / 1000.0);
double megabits = video_bytes_encoded_ * 8 / 1000000.0;
return megabits / seconds;
}
// Mbits per second
double audio_bandwidth() const {
double seconds = (kFrameTimerMs * frames_sent_ / 1000.0);
double megabits = audio_bytes_encoded_ * 8 / 1000000.0;
return megabits / seconds;
}
double desired_video_bitrate() {
return std::min<double>(available_bitrate_,
video_sender_config_.max_bitrate / 1000000.0);
}
bool SimpleGood() {
return frames_lost() <= 1 && late_frames() <= 1 &&
video_bandwidth() > desired_video_bitrate() * 0.8 &&
video_bandwidth() < desired_video_bitrate() * 1.2;
}
private:
FrameReceiverConfig audio_receiver_config_;
FrameReceiverConfig video_receiver_config_;
AudioSenderConfig audio_sender_config_;
VideoSenderConfig video_sender_config_;
base::TimeTicks start_time_;
// These run in "test time"
base::SimpleTestTickClock testing_clock_;
scoped_refptr<test::FakeSingleThreadTaskRunner> task_runner_;
// These run on the sender timeline.
test::SkewedTickClock* testing_clock_sender_;
scoped_refptr<test::SkewedSingleThreadTaskRunner> task_runner_sender_;
// These run on the receiver timeline.
test::SkewedTickClock* testing_clock_receiver_;
scoped_refptr<test::SkewedSingleThreadTaskRunner> task_runner_receiver_;
scoped_refptr<CastEnvironment> cast_environment_sender_;
scoped_refptr<CastEnvironment> cast_environment_receiver_;
LoopBackTransport receiver_to_sender_;
LoopBackTransport sender_to_receiver_;
CastTransportSenderWrapper transport_sender_;
uint64 video_bytes_encoded_;
uint64 audio_bytes_encoded_;
scoped_ptr<CastReceiver> cast_receiver_;
scoped_ptr<CastSender> cast_sender_;
int frames_sent_;
double available_bitrate_;
std::vector<std::pair<base::TimeTicks, base::TimeTicks> > audio_ticks_;
std::vector<std::pair<base::TimeTicks, base::TimeTicks> > video_ticks_;
};
enum CacheResult { FOUND_TRUE, FOUND_FALSE, NOT_FOUND };
template <class T>
class BenchmarkCache {
public:
CacheResult Lookup(const T& x) {
base::AutoLock key(lock_);
for (size_t i = 0; i < results_.size(); i++) {
if (results_[i].second) {
if (x <= results_[i].first) {
VLOG(2) << "TRUE because: " << x.AsString()
<< " <= " << results_[i].first.AsString();
return FOUND_TRUE;
}
} else {
if (x >= results_[i].first) {
VLOG(2) << "FALSE because: " << x.AsString()
<< " >= " << results_[i].first.AsString();
return FOUND_FALSE;
}
}
}
return NOT_FOUND;
}
void Add(const T& x, bool result) {
base::AutoLock key(lock_);
VLOG(2) << "Cache Insert: " << x.AsString() << " = " << result;
results_.push_back(std::make_pair(x, result));
}
private:
base::Lock lock_;
std::vector<std::pair<T, bool> > results_;
};
struct SearchVariable {
SearchVariable() : base(0.0), grade(0.0) {}
SearchVariable(double b, double g) : base(b), grade(g) {}
SearchVariable blend(const SearchVariable& other, double factor) {
CHECK_GE(factor, 0);
CHECK_LE(factor, 1.0);
return SearchVariable(base * (1 - factor) + other.base * factor,
grade * (1 - factor) + other.grade * factor);
}
double value(double x) const { return base + grade * x; }
double base;
double grade;
};
struct SearchVector {
SearchVector blend(const SearchVector& other, double factor) {
SearchVector ret;
ret.bitrate = bitrate.blend(other.bitrate, factor);
ret.latency = latency.blend(other.latency, factor);
ret.packet_drop = packet_drop.blend(other.packet_drop, factor);
return ret;
}
SearchVector average(const SearchVector& other) {
return blend(other, 0.5);
}
MeasuringPoint GetMeasuringPoint(double v) const {
return MeasuringPoint(
bitrate.value(-v), latency.value(v), packet_drop.value(v));
}
std::string AsString(double v) { return GetMeasuringPoint(v).AsString(); }
SearchVariable bitrate;
SearchVariable latency;
SearchVariable packet_drop;
};
class CastBenchmark {
public:
bool RunOnePoint(const SearchVector& v, double multiplier) {
MeasuringPoint p = v.GetMeasuringPoint(multiplier);
VLOG(1) << "RUN: v = " << multiplier << " p = " << p.AsString();
if (p.bitrate <= 0) {
return false;
}
switch (cache_.Lookup(p)) {
case FOUND_TRUE:
return true;
case FOUND_FALSE:
return false;
case NOT_FOUND:
// Keep going
break;
}
bool result = true;
for (int tries = 0; tries < 3 && result; tries++) {
RunOneBenchmark benchmark;
benchmark.Run(p);
result &= benchmark.SimpleGood();
}
cache_.Add(p, result);
return result;
}
void BinarySearch(SearchVector v, double accuracy) {
double min = 0.0;
double max = 1.0;
while (RunOnePoint(v, max)) {
min = max;
max *= 2;
}
while (max - min > accuracy) {
double avg = (min + max) / 2;
if (RunOnePoint(v, avg)) {
min = avg;
} else {
max = avg;
}
}
// Print a data point to stdout.
base::AutoLock key(lock_);
MeasuringPoint p = v.GetMeasuringPoint(min);
fprintf(stdout, "%f %f %f\n", p.bitrate, p.latency, p.percent_packet_drop);
fflush(stdout);
}
void SpanningSearch(int max,
int x,
int y,
int skip,
SearchVector a,
SearchVector b,
SearchVector c,
double accuracy,
std::vector<linked_ptr<base::Thread> >* threads) {
static int thread_num = 0;
if (x > max) return;
if (skip > max) {
if (y > x) return;
SearchVector ab = a.blend(b, static_cast<double>(x) / max);
SearchVector ac = a.blend(c, static_cast<double>(x) / max);
SearchVector v = ab.blend(ac, x == y ? 1.0 : static_cast<double>(y) / x);
thread_num++;
(*threads)[thread_num % threads->size()]->message_loop()->PostTask(
FROM_HERE,
base::Bind(&CastBenchmark::BinarySearch,
base::Unretained(this),
v,
accuracy));
} else {
skip *= 2;
SpanningSearch(max, x, y, skip, a, b, c, accuracy, threads);
SpanningSearch(max, x + skip, y + skip, skip, a, b, c, accuracy, threads);
SpanningSearch(max, x + skip, y, skip, a, b, c, accuracy, threads);
SpanningSearch(max, x, y + skip, skip, a, b, c, accuracy, threads);
}
}
void Run() {
// Spanning search.
std::vector<linked_ptr<base::Thread> > threads;
for (int i = 0; i < 16; i++) {
threads.push_back(make_linked_ptr(new base::Thread(
base::StringPrintf("cast_bench_thread_%d", i))));
threads[i]->Start();
}
if (CommandLine::ForCurrentProcess()->HasSwitch("single-run")) {
SearchVector a;
a.bitrate.base = 100.0;
a.bitrate.grade = 1.0;
a.latency.grade = 1.0;
a.packet_drop.grade = 1.0;
threads[0]->message_loop()->PostTask(
FROM_HERE,
base::Bind(base::IgnoreResult(&CastBenchmark::RunOnePoint),
base::Unretained(this),
a,
1.0));
} else {
SearchVector a, b, c;
a.bitrate.base = b.bitrate.base = c.bitrate.base = 100.0;
a.bitrate.grade = 1.0;
b.latency.grade = 1.0;
c.packet_drop.grade = 1.0;
SpanningSearch(512,
0,
0,
1,
a,
b,
c,
0.01,
&threads);
}
for (size_t i = 0; i < threads.size(); i++) {
threads[i]->Stop();
}
}
private:
BenchmarkCache<MeasuringPoint> cache_;
base::Lock lock_;
};
} // namespace cast
} // namespace media
int main(int argc, char** argv) {
base::AtExitManager at_exit;
CommandLine::Init(argc, argv);
media::cast::CastBenchmark benchmark;
if (getenv("PROFILE_FILE")) {
std::string profile_file(getenv("PROFILE_FILE"));
base::debug::StartProfiling(profile_file);
benchmark.Run();
base::debug::StopProfiling();
} else {
benchmark.Run();
}
}