1 /*
2 * Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include "modules/audio_coding/neteq/tools/neteq_delay_analyzer.h"
12
13 #include <algorithm>
14 #include <fstream>
15 #include <ios>
16 #include <iterator>
17 #include <limits>
18 #include <utility>
19
20 #include "absl/strings/string_view.h"
21 #include "modules/include/module_common_types_public.h"
22 #include "rtc_base/checks.h"
23
24 namespace webrtc {
25 namespace test {
26 namespace {
27 constexpr char kArrivalDelayX[] = "arrival_delay_x";
28 constexpr char kArrivalDelayY[] = "arrival_delay_y";
29 constexpr char kTargetDelayX[] = "target_delay_x";
30 constexpr char kTargetDelayY[] = "target_delay_y";
31 constexpr char kPlayoutDelayX[] = "playout_delay_x";
32 constexpr char kPlayoutDelayY[] = "playout_delay_y";
33
34 // Helper function for NetEqDelayAnalyzer::CreateGraphs. Returns the
35 // interpolated value of a function at the point x. Vector x_vec contains the
36 // sample points, and y_vec contains the function values at these points. The
37 // return value is a linear interpolation between y_vec values.
LinearInterpolate(double x,const std::vector<int64_t> & x_vec,const std::vector<int64_t> & y_vec)38 double LinearInterpolate(double x,
39 const std::vector<int64_t>& x_vec,
40 const std::vector<int64_t>& y_vec) {
41 // Find first element which is larger than x.
42 auto it = std::upper_bound(x_vec.begin(), x_vec.end(), x);
43 if (it == x_vec.end()) {
44 --it;
45 }
46 const size_t upper_ix = it - x_vec.begin();
47
48 size_t lower_ix;
49 if (upper_ix == 0 || x_vec[upper_ix] <= x) {
50 lower_ix = upper_ix;
51 } else {
52 lower_ix = upper_ix - 1;
53 }
54 double y;
55 if (lower_ix == upper_ix) {
56 y = y_vec[lower_ix];
57 } else {
58 RTC_DCHECK_NE(x_vec[lower_ix], x_vec[upper_ix]);
59 y = (x - x_vec[lower_ix]) * (y_vec[upper_ix] - y_vec[lower_ix]) /
60 (x_vec[upper_ix] - x_vec[lower_ix]) +
61 y_vec[lower_ix];
62 }
63 return y;
64 }
65
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,const std::string & terminator="")66 void PrintDelays(const NetEqDelayAnalyzer::Delays& delays,
67 int64_t ref_time_ms,
68 absl::string_view var_name_x,
69 absl::string_view var_name_y,
70 std::ofstream& output,
71 const std::string& terminator = "") {
72 output << var_name_x << " = [ ";
73 for (const std::pair<int64_t, float>& delay : delays) {
74 output << (delay.first - ref_time_ms) / 1000.f << ", ";
75 }
76 output << "]" << terminator << std::endl;
77
78 output << var_name_y << " = [ ";
79 for (const std::pair<int64_t, float>& delay : delays) {
80 output << delay.second << ", ";
81 }
82 output << "]" << terminator << std::endl;
83 }
84
85 } // namespace
86
AfterInsertPacket(const test::NetEqInput::PacketData & packet,NetEq * neteq)87 void NetEqDelayAnalyzer::AfterInsertPacket(
88 const test::NetEqInput::PacketData& packet,
89 NetEq* neteq) {
90 data_.insert(
91 std::make_pair(packet.header.timestamp, TimingData(packet.time_ms)));
92 ssrcs_.insert(packet.header.ssrc);
93 payload_types_.insert(packet.header.payloadType);
94 }
95
BeforeGetAudio(NetEq * neteq)96 void NetEqDelayAnalyzer::BeforeGetAudio(NetEq* neteq) {
97 last_sync_buffer_ms_ = neteq->SyncBufferSizeMs();
98 }
99
AfterGetAudio(int64_t time_now_ms,const AudioFrame & audio_frame,bool,NetEq * neteq)100 void NetEqDelayAnalyzer::AfterGetAudio(int64_t time_now_ms,
101 const AudioFrame& audio_frame,
102 bool /*muted*/,
103 NetEq* neteq) {
104 get_audio_time_ms_.push_back(time_now_ms);
105 // Check what timestamps were decoded in the last GetAudio call.
106 std::vector<uint32_t> dec_ts = neteq->LastDecodedTimestamps();
107 // Find those timestamps in data_, insert their decoding time and sync
108 // delay.
109 for (uint32_t ts : dec_ts) {
110 auto it = data_.find(ts);
111 if (it == data_.end()) {
112 // This is a packet that was split out from another packet. Skip it.
113 continue;
114 }
115 auto& it_timing = it->second;
116 RTC_CHECK(!it_timing.decode_get_audio_count)
117 << "Decode time already written";
118 it_timing.decode_get_audio_count = get_audio_count_;
119 RTC_CHECK(!it_timing.sync_delay_ms) << "Decode time already written";
120 it_timing.sync_delay_ms = last_sync_buffer_ms_;
121 it_timing.target_delay_ms = neteq->TargetDelayMs();
122 it_timing.current_delay_ms = neteq->FilteredCurrentDelayMs();
123 }
124 last_sample_rate_hz_ = audio_frame.sample_rate_hz_;
125 ++get_audio_count_;
126 }
127
CreateGraphs(Delays * arrival_delay_ms,Delays * corrected_arrival_delay_ms,Delays * playout_delay_ms,Delays * target_delay_ms) const128 void NetEqDelayAnalyzer::CreateGraphs(Delays* arrival_delay_ms,
129 Delays* corrected_arrival_delay_ms,
130 Delays* playout_delay_ms,
131 Delays* target_delay_ms) const {
132 if (get_audio_time_ms_.empty()) {
133 return;
134 }
135 // Create nominal_get_audio_time_ms, a vector starting at
136 // get_audio_time_ms_[0] and increasing by 10 for each element.
137 std::vector<int64_t> nominal_get_audio_time_ms(get_audio_time_ms_.size());
138 nominal_get_audio_time_ms[0] = get_audio_time_ms_[0];
139 std::transform(
140 nominal_get_audio_time_ms.begin(), nominal_get_audio_time_ms.end() - 1,
141 nominal_get_audio_time_ms.begin() + 1, [](int64_t& x) { return x + 10; });
142 RTC_DCHECK(
143 std::is_sorted(get_audio_time_ms_.begin(), get_audio_time_ms_.end()));
144
145 std::vector<double> rtp_timestamps_ms;
146 double offset = std::numeric_limits<double>::max();
147 TimestampUnwrapper unwrapper;
148 // This loop traverses data_ and populates rtp_timestamps_ms as well as
149 // calculates the base offset.
150 for (auto& d : data_) {
151 rtp_timestamps_ms.push_back(
152 static_cast<double>(unwrapper.Unwrap(d.first)) /
153 rtc::CheckedDivExact(last_sample_rate_hz_, 1000));
154 offset =
155 std::min(offset, d.second.arrival_time_ms - rtp_timestamps_ms.back());
156 }
157
158 // This loop traverses the data again and populates the graph vectors. The
159 // reason to have two loops and traverse twice is that the offset cannot be
160 // known until the first traversal is done. Meanwhile, the final offset must
161 // be known already at the start of this second loop.
162 size_t i = 0;
163 for (const auto& data : data_) {
164 const double offset_send_time_ms = rtp_timestamps_ms[i++] + offset;
165 const auto& timing = data.second;
166 corrected_arrival_delay_ms->push_back(std::make_pair(
167 timing.arrival_time_ms,
168 LinearInterpolate(timing.arrival_time_ms, get_audio_time_ms_,
169 nominal_get_audio_time_ms) -
170 offset_send_time_ms));
171 arrival_delay_ms->push_back(std::make_pair(
172 timing.arrival_time_ms, timing.arrival_time_ms - offset_send_time_ms));
173
174 if (timing.decode_get_audio_count) {
175 // This packet was decoded.
176 RTC_DCHECK(timing.sync_delay_ms);
177 const int64_t get_audio_time =
178 *timing.decode_get_audio_count * 10 + get_audio_time_ms_[0];
179 const float playout_ms =
180 get_audio_time + *timing.sync_delay_ms - offset_send_time_ms;
181 playout_delay_ms->push_back(std::make_pair(get_audio_time, playout_ms));
182 RTC_DCHECK(timing.target_delay_ms);
183 RTC_DCHECK(timing.current_delay_ms);
184 const float target =
185 playout_ms - *timing.current_delay_ms + *timing.target_delay_ms;
186 target_delay_ms->push_back(std::make_pair(get_audio_time, target));
187 }
188 }
189 }
190
CreateMatlabScript(const std::string & script_name) const191 void NetEqDelayAnalyzer::CreateMatlabScript(
192 const std::string& script_name) const {
193 Delays arrival_delay_ms;
194 Delays corrected_arrival_delay_ms;
195 Delays playout_delay_ms;
196 Delays target_delay_ms;
197 CreateGraphs(&arrival_delay_ms, &corrected_arrival_delay_ms,
198 &playout_delay_ms, &target_delay_ms);
199
200 // Maybe better to find the actually smallest timestamp, to surely avoid
201 // x-axis starting from negative.
202 const int64_t ref_time_ms = arrival_delay_ms.front().first;
203
204 // Create an output file stream to Matlab script file.
205 std::ofstream output(script_name);
206
207 PrintDelays(corrected_arrival_delay_ms, ref_time_ms, kArrivalDelayX,
208 kArrivalDelayY, output, ";");
209
210 // PrintDelays(corrected_arrival_delay_x, kCorrectedArrivalDelayX,
211 // kCorrectedArrivalDelayY, output);
212
213 PrintDelays(playout_delay_ms, ref_time_ms, kPlayoutDelayX, kPlayoutDelayY,
214 output, ";");
215
216 PrintDelays(target_delay_ms, ref_time_ms, kTargetDelayX, kTargetDelayY,
217 output, ";");
218
219 output << "h=plot(" << kArrivalDelayX << ", " << kArrivalDelayY << ", "
220 << kTargetDelayX << ", " << kTargetDelayY << ", 'g.', "
221 << kPlayoutDelayX << ", " << kPlayoutDelayY << ");" << std::endl;
222 output << "set(h(1),'color',0.75*[1 1 1]);" << std::endl;
223 output << "set(h(2),'markersize',6);" << std::endl;
224 output << "set(h(3),'linew',1.5);" << std::endl;
225 output << "ax1=axis;" << std::endl;
226 output << "axis tight" << std::endl;
227 output << "ax2=axis;" << std::endl;
228 output << "axis([ax2(1:3) ax1(4)])" << std::endl;
229 output << "xlabel('time [s]');" << std::endl;
230 output << "ylabel('relative delay [ms]');" << std::endl;
231 if (!ssrcs_.empty()) {
232 auto ssrc_it = ssrcs_.cbegin();
233 output << "title('SSRC: 0x" << std::hex << static_cast<int64_t>(*ssrc_it++);
234 while (ssrc_it != ssrcs_.end()) {
235 output << ", 0x" << std::hex << static_cast<int64_t>(*ssrc_it++);
236 }
237 output << std::dec;
238 auto pt_it = payload_types_.cbegin();
239 output << "; Payload Types: " << *pt_it++;
240 while (pt_it != payload_types_.end()) {
241 output << ", " << *pt_it++;
242 }
243 output << "');" << std::endl;
244 }
245 }
246
CreatePythonScript(const std::string & script_name) const247 void NetEqDelayAnalyzer::CreatePythonScript(
248 const std::string& script_name) const {
249 Delays arrival_delay_ms;
250 Delays corrected_arrival_delay_ms;
251 Delays playout_delay_ms;
252 Delays target_delay_ms;
253 CreateGraphs(&arrival_delay_ms, &corrected_arrival_delay_ms,
254 &playout_delay_ms, &target_delay_ms);
255
256 // Maybe better to find the actually smallest timestamp, to surely avoid
257 // x-axis starting from negative.
258 const int64_t ref_time_ms = arrival_delay_ms.front().first;
259
260 // Create an output file stream to the python script file.
261 std::ofstream output(script_name);
262
263 // Necessary includes
264 output << "import numpy as np" << std::endl;
265 output << "import matplotlib.pyplot as plt" << std::endl;
266
267 PrintDelays(corrected_arrival_delay_ms, ref_time_ms, kArrivalDelayX,
268 kArrivalDelayY, output);
269
270 // PrintDelays(corrected_arrival_delay_x, kCorrectedArrivalDelayX,
271 // kCorrectedArrivalDelayY, output);
272
273 PrintDelays(playout_delay_ms, ref_time_ms, kPlayoutDelayX, kPlayoutDelayY,
274 output);
275
276 PrintDelays(target_delay_ms, ref_time_ms, kTargetDelayX, kTargetDelayY,
277 output);
278
279 output << "if __name__ == '__main__':" << std::endl;
280 output << " h=plt.plot(" << kArrivalDelayX << ", " << kArrivalDelayY << ", "
281 << kTargetDelayX << ", " << kTargetDelayY << ", 'g.', "
282 << kPlayoutDelayX << ", " << kPlayoutDelayY << ")" << std::endl;
283 output << " plt.setp(h[0],'color',[.75, .75, .75])" << std::endl;
284 output << " plt.setp(h[1],'markersize',6)" << std::endl;
285 output << " plt.setp(h[2],'linewidth',1.5)" << std::endl;
286 output << " plt.axis('tight')" << std::endl;
287 output << " plt.xlabel('time [s]')" << std::endl;
288 output << " plt.ylabel('relative delay [ms]')" << std::endl;
289 if (!ssrcs_.empty()) {
290 auto ssrc_it = ssrcs_.cbegin();
291 output << " plt.title('SSRC: 0x" << std::hex
292 << static_cast<int64_t>(*ssrc_it++);
293 while (ssrc_it != ssrcs_.end()) {
294 output << ", 0x" << std::hex << static_cast<int64_t>(*ssrc_it++);
295 }
296 output << std::dec;
297 auto pt_it = payload_types_.cbegin();
298 output << "; Payload Types: " << *pt_it++;
299 while (pt_it != payload_types_.end()) {
300 output << ", " << *pt_it++;
301 }
302 output << "')" << std::endl;
303 }
304 output << " plt.show()" << std::endl;
305 }
306
307 } // namespace test
308 } // namespace webrtc
309