Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(30)

Issues Search
    My Issues | Starred     Open | Closed | All

Side by Side Diff: third_party/WebKit/LayoutTests/webaudio/resources/oscillator-testing.js

Issue 2728613003: Add support creating and saving a new reference file. (Closed)
Patch Set: Fix typo Created 3 years, 9 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View unified diff | Download patch
« no previous file with comments | « third_party/WebKit/LayoutTests/webaudio/resources/audit-util.js ('k') | no next file » | no next file with comments »
Toggle Intra-line Diffs ('i') | Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
OLDNEW
1 // Notes about generated waveforms: 1 // Notes about generated waveforms:
2 // 2 //
3 // QUESTION: Why does the wave shape not look like the exact shape (sharp edges) ? 3 // QUESTION: Why does the wave shape not look like the exact shape (sharp edges) ?
4 // ANSWER: Because a shape with sharp edges has infinitely high frequency conten t. 4 // ANSWER: Because a shape with sharp edges has infinitely high frequency conten t.
5 // Since a digital audio signal must be band-limited based on the nyquist freque ncy (half the sample-rate) 5 // Since a digital audio signal must be band-limited based on the nyquist freque ncy (half the sample-rate)
6 // in order to avoid aliasing, this creates more rounded edges and "ringing" in the 6 // in order to avoid aliasing, this creates more rounded edges and "ringing" in the
7 // appearance of the waveform. See Nyquist-Shannon sampling theorem: 7 // appearance of the waveform. See Nyquist-Shannon sampling theorem:
8 // http://en.wikipedia.org/wiki/Nyquist%E2%80%93Shannon_sampling_theorem 8 // http://en.wikipedia.org/wiki/Nyquist%E2%80%93Shannon_sampling_theorem
9 // 9 //
10 // QUESTION: Why does the very end of the generated signal appear to get slightl y weaker? 10 // QUESTION: Why does the very end of the generated signal appear to get slightl y weaker?
11 // ANSWER: This is an artifact of the algorithm to avoid aliasing. 11 // ANSWER: This is an artifact of the algorithm to avoid aliasing.
12 // 12 //
13 // QUESTION: Since the tests compare the actual result with an expected referenc e file, how are the 13 // QUESTION: Since the tests compare the actual result with an expected referenc e file, how are the
14 // reference files created? 14 // reference files created?
15 // ANSWER: Create an html with the following contents in the webaudio directory. Then run a layout 15 // ANSWER: Run the test in a browser. When the test completes, a
16 // test on this file. A new file names "<file>-actual.wav" is created that cont ains the new result 16 // generated reference file with the name "<file>-actual.wav" is
17 // that can be used as the new expected reference file. Replace the "sine" belo w with the 17 // automatically downloaded. Use this as the new reference, after
18 // oscillator type that you want to use. 18 // carefully inspecting to see if this is correct.
19 // 19 //
20 // <!doctype html>
21 // <html>
22 // <head>
23 // <script src="../resources/testharness.js"></script>
24 // <script src="resources/oscillator-testing.js"></script>
25 // <script src="resources/audit-util.js"></script>
26 // </head>
27 // <body>
28 // <script>
29 // OscillatorTestingUtils.createNewReference("sine");
30 // </script>
31 // </body>
32 // </html>
33 20
34 OscillatorTestingUtils = (function () { 21 OscillatorTestingUtils = (function () {
35 22
36 var sampleRate = 44100.0; 23 var sampleRate = 44100.0;
37 var nyquist = 0.5 * sampleRate; 24 var nyquist = 0.5 * sampleRate;
38 var lengthInSeconds = 4; 25 var lengthInSeconds = 4;
39 var lowFrequency = 10; 26 var lowFrequency = 10;
40 var highFrequency = nyquist + 2000; // go slightly higher than nyquist to make s ure we generate silence there 27 var highFrequency = nyquist + 2000; // go slightly higher than nyquist to make s ure we generate silence there
41 var context = 0; 28 var context = 0;
42 29
(...skipping 62 matching lines...) Expand 10 before | Expand all | Expand 10 after
105 } 92 }
106 93
107 function loadReferenceAndRunTest(context, oscType, task, should) { 94 function loadReferenceAndRunTest(context, oscType, task, should) {
108 var bufferLoader = new BufferLoader( 95 var bufferLoader = new BufferLoader(
109 context, 96 context,
110 [ "../Oscillator/oscillator-" + oscType + "-expected.wav" ], 97 [ "../Oscillator/oscillator-" + oscType + "-expected.wav" ],
111 function (bufferList) { 98 function (bufferList) {
112 reference = bufferList[0].getChannelData(0); 99 reference = bufferList[0].getChannelData(0);
113 generateExponentialOscillatorSweep(context, oscType); 100 generateExponentialOscillatorSweep(context, oscType);
114 context.oncomplete = () => { 101 context.oncomplete = () => {
115 checkResult(event, should); 102 checkResult(event, should, oscType);
116 task.done(); 103 task.done();
117 }; 104 };
118 context.startRendering(); 105 context.startRendering();
119 }); 106 });
120 107
121 bufferLoader.load(); 108 bufferLoader.load();
122 } 109 }
123 110
124 function checkResult (event, should) { 111 function checkResult (event, should, oscType) {
125 let renderedData = event.renderedBuffer.getChannelData(0); 112 let renderedData = event.renderedBuffer.getChannelData(0);
126 // Compute signal to noise ratio between the result and the reference. Also keep track 113 // Compute signal to noise ratio between the result and the reference. Also keep track
127 // of the max difference (and position). 114 // of the max difference (and position).
128 115
129 var maxError = -1; 116 var maxError = -1;
130 var errorPosition = -1; 117 var errorPosition = -1;
131 var diffCount = 0; 118 var diffCount = 0;
132 119
133 for (var k = 0; k < renderedData.length; ++k) { 120 for (var k = 0; k < renderedData.length; ++k) {
134 var diff = renderedData[k] - reference[k]; 121 var diff = renderedData[k] - reference[k];
(...skipping 13 matching lines...) Expand all
148 var snr = calculateSNR(signalPower, noisePower); 135 var snr = calculateSNR(signalPower, noisePower);
149 should(snr, "SNR") 136 should(snr, "SNR")
150 .beGreaterThanOrEqualTo(thresholdSNR); 137 .beGreaterThanOrEqualTo(thresholdSNR);
151 should(maxError * waveScaleFactor, "Maximum difference in ulp (16-bits)") 138 should(maxError * waveScaleFactor, "Maximum difference in ulp (16-bits)")
152 .beLessThanOrEqualTo(thresholdDiff * waveScaleFactor); 139 .beLessThanOrEqualTo(thresholdDiff * waveScaleFactor);
153 140
154 should(diffCount, 141 should(diffCount,
155 "Number of differences between actual and expected result out of " 142 "Number of differences between actual and expected result out of "
156 + renderedData.length + " frames") 143 + renderedData.length + " frames")
157 .beLessThanOrEqualTo(thresholdDiffCount); 144 .beLessThanOrEqualTo(thresholdDiffCount);
145
146 var filename = "oscillator-" + oscType + "-actual.wav";
147 if (downloadAudioBuffer(event.renderedBuffer, filename))
148 should(true, "Saved reference file").message(filename, "");
158 } 149 }
159 150
160 function setThresholds(thresholds) { 151 function setThresholds(thresholds) {
161 thresholdSNR = thresholds.snr; 152 thresholdSNR = thresholds.snr;
162 thresholdDiff = thresholds.maxDiff / waveScaleFactor; 153 thresholdDiff = thresholds.maxDiff / waveScaleFactor;
163 thresholdDiffCount = thresholds.diffCount; 154 thresholdDiffCount = thresholds.diffCount;
164 } 155 }
165 156
166 function runTest(context, oscType, description, task, should) { 157 function runTest(context, oscType, description, task, should) {
167 loadReferenceAndRunTest(context, oscType, task, should); 158 loadReferenceAndRunTest(context, oscType, task, should);
(...skipping 18 matching lines...) Expand all
186 thresholdSNR: thresholdSNR, 177 thresholdSNR: thresholdSNR,
187 thresholdDiff: thresholdDiff, 178 thresholdDiff: thresholdDiff,
188 thresholdDiffCount: thresholdDiffCount, 179 thresholdDiffCount: thresholdDiffCount,
189 waveScaleFactor: waveScaleFactor, 180 waveScaleFactor: waveScaleFactor,
190 setThresholds: setThresholds, 181 setThresholds: setThresholds,
191 runTest: runTest, 182 runTest: runTest,
192 createNewReference: createNewReference, 183 createNewReference: createNewReference,
193 }; 184 };
194 185
195 }()); 186 }());
OLDNEW
« no previous file with comments | « third_party/WebKit/LayoutTests/webaudio/resources/audit-util.js ('k') | no next file » | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698