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/*
* Copyright (c) 2017 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 "modules/audio_coding/neteq/tools/neteq_delay_analyzer.h"
#include <algorithm>
#include <fstream>
#include <ios>
#include <iterator>
#include <limits>
#include <utility>
#include "absl/strings/string_view.h"
#include "rtc_base/checks.h"
#include "rtc_base/numerics/sequence_number_unwrapper.h"
namespace webrtc {
namespace test {
namespace {
constexpr char kArrivalDelayX[] = "arrival_delay_x";
constexpr char kArrivalDelayY[] = "arrival_delay_y";
constexpr char kTargetDelayX[] = "target_delay_x";
constexpr char kTargetDelayY[] = "target_delay_y";
constexpr char kPlayoutDelayX[] = "playout_delay_x";
constexpr char kPlayoutDelayY[] = "playout_delay_y";
// Helper function for NetEqDelayAnalyzer::CreateGraphs. Returns the
// interpolated value of a function at the point x. Vector x_vec contains the
// sample points, and y_vec contains the function values at these points. The
// return value is a linear interpolation between y_vec values.
double LinearInterpolate(double x,
const std::vector<int64_t>& x_vec,
const std::vector<int64_t>& y_vec) {
// Find first element which is larger than x.
auto it = std::upper_bound(x_vec.begin(), x_vec.end(), x);
if (it == x_vec.end()) {
--it;
}
const size_t upper_ix = it - x_vec.begin();
size_t lower_ix;
if (upper_ix == 0 || x_vec[upper_ix] <= x) {
lower_ix = upper_ix;
} else {
lower_ix = upper_ix - 1;
}
double y;
if (lower_ix == upper_ix) {
y = y_vec[lower_ix];
} else {
RTC_DCHECK_NE(x_vec[lower_ix], x_vec[upper_ix]);
y = (x - x_vec[lower_ix]) * (y_vec[upper_ix] - y_vec[lower_ix]) /
(x_vec[upper_ix] - x_vec[lower_ix]) +
y_vec[lower_ix];
}
return y;
}
void PrintDelays(const NetEqDelayAnalyzer::Delays& delays,
int64_t ref_time_ms,
absl::string_view var_name_x,
absl::string_view var_name_y,
std::ofstream& output,
absl::string_view terminator = "") {
output << var_name_x << " = [ ";
for (const std::pair<int64_t, float>& delay : delays) {
output << (delay.first - ref_time_ms) / 1000.f << ", ";
}
output << "]" << terminator << std::endl;
output << var_name_y << " = [ ";
for (const std::pair<int64_t, float>& delay : delays) {
output << delay.second << ", ";
}
output << "]" << terminator << std::endl;
}
} // namespace
void NetEqDelayAnalyzer::AfterInsertPacket(
const test::NetEqInput::PacketData& packet,
NetEq* neteq) {
data_.insert(
std::make_pair(packet.header.timestamp, TimingData(packet.time_ms)));
ssrcs_.insert(packet.header.ssrc);
payload_types_.insert(packet.header.payloadType);
}
void NetEqDelayAnalyzer::BeforeGetAudio(NetEq* neteq) {
last_sync_buffer_ms_ = neteq->SyncBufferSizeMs();
}
void NetEqDelayAnalyzer::AfterGetAudio(int64_t time_now_ms,
const AudioFrame& audio_frame,
bool /*muted*/,
NetEq* neteq) {
get_audio_time_ms_.push_back(time_now_ms);
for (const RtpPacketInfo& info : audio_frame.packet_infos_) {
auto it = data_.find(info.rtp_timestamp());
if (it == data_.end()) {
// This is a packet that was split out from another packet. Skip it.
continue;
}
auto& it_timing = it->second;
RTC_CHECK(!it_timing.decode_get_audio_count)
<< "Decode time already written";
it_timing.decode_get_audio_count = get_audio_count_;
RTC_CHECK(!it_timing.sync_delay_ms) << "Decode time already written";
it_timing.sync_delay_ms = last_sync_buffer_ms_;
it_timing.target_delay_ms = neteq->TargetDelayMs();
it_timing.current_delay_ms = neteq->FilteredCurrentDelayMs();
}
last_sample_rate_hz_ = audio_frame.sample_rate_hz_;
++get_audio_count_;
}
void NetEqDelayAnalyzer::CreateGraphs(Delays* arrival_delay_ms,
Delays* corrected_arrival_delay_ms,
Delays* playout_delay_ms,
Delays* target_delay_ms) const {
if (get_audio_time_ms_.empty()) {
return;
}
// Create nominal_get_audio_time_ms, a vector starting at
// get_audio_time_ms_[0] and increasing by 10 for each element.
std::vector<int64_t> nominal_get_audio_time_ms(get_audio_time_ms_.size());
nominal_get_audio_time_ms[0] = get_audio_time_ms_[0];
std::transform(
nominal_get_audio_time_ms.begin(), nominal_get_audio_time_ms.end() - 1,
nominal_get_audio_time_ms.begin() + 1, [](int64_t& x) { return x + 10; });
RTC_DCHECK(
std::is_sorted(get_audio_time_ms_.begin(), get_audio_time_ms_.end()));
std::vector<double> rtp_timestamps_ms;
double offset = std::numeric_limits<double>::max();
RtpTimestampUnwrapper unwrapper;
// This loop traverses data_ and populates rtp_timestamps_ms as well as
// calculates the base offset.
for (auto& d : data_) {
rtp_timestamps_ms.push_back(
static_cast<double>(unwrapper.Unwrap(d.first)) /
rtc::CheckedDivExact(last_sample_rate_hz_, 1000));
offset =
std::min(offset, d.second.arrival_time_ms - rtp_timestamps_ms.back());
}
// This loop traverses the data again and populates the graph vectors. The
// reason to have two loops and traverse twice is that the offset cannot be
// known until the first traversal is done. Meanwhile, the final offset must
// be known already at the start of this second loop.
size_t i = 0;
for (const auto& data : data_) {
const double offset_send_time_ms = rtp_timestamps_ms[i++] + offset;
const auto& timing = data.second;
corrected_arrival_delay_ms->push_back(std::make_pair(
timing.arrival_time_ms,
LinearInterpolate(timing.arrival_time_ms, get_audio_time_ms_,
nominal_get_audio_time_ms) -
offset_send_time_ms));
arrival_delay_ms->push_back(std::make_pair(
timing.arrival_time_ms, timing.arrival_time_ms - offset_send_time_ms));
if (timing.decode_get_audio_count) {
// This packet was decoded.
RTC_DCHECK(timing.sync_delay_ms);
const int64_t get_audio_time =
*timing.decode_get_audio_count * 10 + get_audio_time_ms_[0];
const float playout_ms =
get_audio_time + *timing.sync_delay_ms - offset_send_time_ms;
playout_delay_ms->push_back(std::make_pair(get_audio_time, playout_ms));
RTC_DCHECK(timing.target_delay_ms);
RTC_DCHECK(timing.current_delay_ms);
const float target =
playout_ms - *timing.current_delay_ms + *timing.target_delay_ms;
target_delay_ms->push_back(std::make_pair(get_audio_time, target));
}
}
}
void NetEqDelayAnalyzer::CreateMatlabScript(
absl::string_view script_name) const {
Delays arrival_delay_ms;
Delays corrected_arrival_delay_ms;
Delays playout_delay_ms;
Delays target_delay_ms;
CreateGraphs(&arrival_delay_ms, &corrected_arrival_delay_ms,
&playout_delay_ms, &target_delay_ms);
// Maybe better to find the actually smallest timestamp, to surely avoid
// x-axis starting from negative.
const int64_t ref_time_ms = arrival_delay_ms.front().first;
// Create an output file stream to Matlab script file.
std::ofstream output(std::string{script_name});
PrintDelays(corrected_arrival_delay_ms, ref_time_ms, kArrivalDelayX,
kArrivalDelayY, output, ";");
// PrintDelays(corrected_arrival_delay_x, kCorrectedArrivalDelayX,
// kCorrectedArrivalDelayY, output);
PrintDelays(playout_delay_ms, ref_time_ms, kPlayoutDelayX, kPlayoutDelayY,
output, ";");
PrintDelays(target_delay_ms, ref_time_ms, kTargetDelayX, kTargetDelayY,
output, ";");
output << "h=plot(" << kArrivalDelayX << ", " << kArrivalDelayY << ", "
<< kTargetDelayX << ", " << kTargetDelayY << ", 'g.', "
<< kPlayoutDelayX << ", " << kPlayoutDelayY << ");" << std::endl;
output << "set(h(1),'color',0.75*[1 1 1]);" << std::endl;
output << "set(h(2),'markersize',6);" << std::endl;
output << "set(h(3),'linew',1.5);" << std::endl;
output << "ax1=axis;" << std::endl;
output << "axis tight" << std::endl;
output << "ax2=axis;" << std::endl;
output << "axis([ax2(1:3) ax1(4)])" << std::endl;
output << "xlabel('time [s]');" << std::endl;
output << "ylabel('relative delay [ms]');" << std::endl;
if (!ssrcs_.empty()) {
auto ssrc_it = ssrcs_.cbegin();
output << "title('SSRC: 0x" << std::hex << static_cast<int64_t>(*ssrc_it++);
while (ssrc_it != ssrcs_.end()) {
output << ", 0x" << std::hex << static_cast<int64_t>(*ssrc_it++);
}
output << std::dec;
auto pt_it = payload_types_.cbegin();
output << "; Payload Types: " << *pt_it++;
while (pt_it != payload_types_.end()) {
output << ", " << *pt_it++;
}
output << "');" << std::endl;
}
}
void NetEqDelayAnalyzer::CreatePythonScript(
absl::string_view script_name) const {
Delays arrival_delay_ms;
Delays corrected_arrival_delay_ms;
Delays playout_delay_ms;
Delays target_delay_ms;
CreateGraphs(&arrival_delay_ms, &corrected_arrival_delay_ms,
&playout_delay_ms, &target_delay_ms);
// Maybe better to find the actually smallest timestamp, to surely avoid
// x-axis starting from negative.
const int64_t ref_time_ms = arrival_delay_ms.front().first;
// Create an output file stream to the python script file.
std::ofstream output(std::string{script_name});
// Necessary includes
output << "import numpy as np" << std::endl;
output << "import matplotlib.pyplot as plt" << std::endl;
PrintDelays(corrected_arrival_delay_ms, ref_time_ms, kArrivalDelayX,
kArrivalDelayY, output);
// PrintDelays(corrected_arrival_delay_x, kCorrectedArrivalDelayX,
// kCorrectedArrivalDelayY, output);
PrintDelays(playout_delay_ms, ref_time_ms, kPlayoutDelayX, kPlayoutDelayY,
output);
PrintDelays(target_delay_ms, ref_time_ms, kTargetDelayX, kTargetDelayY,
output);
output << "if __name__ == '__main__':" << std::endl;
output << " h=plt.plot(" << kArrivalDelayX << ", " << kArrivalDelayY << ", "
<< kTargetDelayX << ", " << kTargetDelayY << ", 'g.', "
<< kPlayoutDelayX << ", " << kPlayoutDelayY << ")" << std::endl;
output << " plt.setp(h[0],'color',[.75, .75, .75])" << std::endl;
output << " plt.setp(h[1],'markersize',6)" << std::endl;
output << " plt.setp(h[2],'linewidth',1.5)" << std::endl;
output << " plt.axis('tight')" << std::endl;
output << " plt.xlabel('time [s]')" << std::endl;
output << " plt.ylabel('relative delay [ms]')" << std::endl;
if (!ssrcs_.empty()) {
auto ssrc_it = ssrcs_.cbegin();
output << " plt.legend((\"arrival delay\", \"target delay\", \"playout "
"delay\"))"
<< std::endl;
output << " plt.title('SSRC: 0x" << std::hex
<< static_cast<int64_t>(*ssrc_it++);
while (ssrc_it != ssrcs_.end()) {
output << ", 0x" << std::hex << static_cast<int64_t>(*ssrc_it++);
}
output << std::dec;
auto pt_it = payload_types_.cbegin();
output << "; Payload Types: " << *pt_it++;
while (pt_it != payload_types_.end()) {
output << ", " << *pt_it++;
}
output << "')" << std::endl;
}
output << " plt.show()" << std::endl;
}
} // namespace test
} // namespace webrtc