third_party/blink/web_tests/webaudio/Analyser/realtimeanalyser-freq-data-smoothing.html - chromium/src - Git at Google

 <!DOCTYPE html>
 <html>
   <head>
     <title>
       Test Analyser getFloatFrequencyData and getByteFrequencyData, Smoothing
     </title>
     <script src="../../resources/testharness.js"></script>
     <script src="../../resources/testharnessreport.js"></script>
     <script src="../resources/audit-util.js"></script>
     <script src="../resources/audit.js"></script>
     <script src="../resources/realtimeanalyser-testing.js"></script>
     <script src="../resources/fft.js"></script>
   </head>
   <body>
     <script id="layout-test-code">
       // Use a power of two to eliminate any round-off in the computation of the
       // times for context.suspend().
       let sampleRate = 32768;

       // The largest FFT size for the analyser node is 32768.  We want to render
       // longer than this so that we have at least one complete buffer of data
       // of 32768 samples.
       let renderFrames = 2 * 32768;
       let renderDuration = renderFrames / sampleRate;

       let audit = Audit.createTaskRunner();

       // Do one basic test of smoothing of the FFT data.
       audit.define('smoothing test', (task, should) => {
         // Test only 512-point FFT.  The size isn't too important as long as
         // it's greater than 128 (a rendering quantum).
         let options = {order: 9, smoothing: 0.5, floatRelError: 5.9207e-6};

         let success = true;

         let graph = createGraph(options);

         context = graph.context;
         analyser = graph.analyser;

         let smoothedFloatResult = new Float32Array(analyser.frequencyBinCount);
         smoothedFloatResult.fill(0);

         // Stop after one analyser frame to get the initial FFT
         let suspendFrame = analyser.fftSize;
         context.suspend(suspendFrame / sampleRate)
             .then(function() {
               let timeData = new Float32Array(analyser.fftSize);
               let freqData = new Float32Array(analyser.frequencyBinCount);
               analyser.getFloatTimeDomainData(timeData);
               analyser.getFloatFrequencyData(freqData);

               let expectedFreq = computeFFTMagnitude(timeData, options.order);
               smoothFFT(smoothedFloatResult, expectedFreq, options.smoothing);

               let message = 'First ' + analyser.fftSize +
                   '-point FFT at frame ' + (context.currentTime * sampleRate);
               let comparison = compareFloatFreq(
                   message, freqData, smoothedFloatResult.map(linearToDb),
                   should, options);
               success = success && comparison.success;

               // Test the byte frequency data.
               let byteFreqData = new Uint8Array(analyser.frequencyBinCount);
               analyser.getByteFrequencyData(byteFreqData);

               // Convert the expected float frequency data to byte data.
               let expectedByteData = convertFloatToByte(
                   smoothedFloatResult.map(linearToDb), analyser.minDecibels,
                   analyser.maxDecibels);

               should(byteFreqData, analyser.fftSize + '-point byte FFT')
                   .beCloseToArray(expectedByteData, 0);

             })
             .then(context.resume.bind(context));

         // Skip an analyser frame and grab another to verify that the smoothing
         // is done correctly.
         suspendFrame += 2 * analyser.fftSize;
         context.suspend(suspendFrame / sampleRate)
             .then(function() {
               let timeData = new Float32Array(analyser.fftSize);
               let freqDataInDb = new Float32Array(analyser.frequencyBinCount);

               // Grab the time domain and frequency domain data
               analyser.getFloatTimeDomainData(timeData);
               analyser.getFloatFrequencyData(freqDataInDb);

               let newFreqData = computeFFTMagnitude(timeData, options.order);
               // Smooth the data together

               smoothFFT(smoothedFloatResult, newFreqData, options.smoothing);
               let message = 'Smoothed ' + analyser.fftSize +
                   '-point FFT at frame ' + (context.currentTime * sampleRate);
               let comparison = compareFloatFreq(
                   message, freqDataInDb, smoothedFloatResult.map(linearToDb),
                   should, {
                     order: options.order,
                     smoothing: options.smoothing,
                     floatRelError: 2.5332e-5
                   });
               success = success && comparison.success;

               // Test the byte frequency data.
               let byteFreqData = new Uint8Array(analyser.frequencyBinCount);
               analyser.getByteFrequencyData(byteFreqData);

               // Convert the expected float frequency data to byte data.
               let expectedByteData = convertFloatToByte(
                   smoothedFloatResult.map(linearToDb), analyser.minDecibels,
                   analyser.maxDecibels);

               should(byteFreqData, analyser.fftSize + '-point byte FFT')
                   .beCloseToArray(expectedByteData, 0);

             })
             .then(context.resume.bind(context));

         context.startRendering().then(() => task.done());
       });

       audit.run();
     </script>
   </body>
 </html>
	<!DOCTYPE html>
	<html>
	<head>
	<title>
	Test Analyser getFloatFrequencyData and getByteFrequencyData, Smoothing
	</title>
	<script src="../../resources/testharness.js"></script>
	<script src="../../resources/testharnessreport.js"></script>
	<script src="../resources/audit-util.js"></script>
	<script src="../resources/audit.js"></script>
	<script src="../resources/realtimeanalyser-testing.js"></script>
	<script src="../resources/fft.js"></script>
	</head>
	<body>
	<script id="layout-test-code">
	// Use a power of two to eliminate any round-off in the computation of the
	// times for context.suspend().
	let sampleRate = 32768;

	// The largest FFT size for the analyser node is 32768. We want to render
	// longer than this so that we have at least one complete buffer of data
	// of 32768 samples.
	let renderFrames = 2 * 32768;
	let renderDuration = renderFrames / sampleRate;

	let audit = Audit.createTaskRunner();

	// Do one basic test of smoothing of the FFT data.
	audit.define('smoothing test', (task, should) => {
	// Test only 512-point FFT. The size isn't too important as long as
	// it's greater than 128 (a rendering quantum).
	let options = {order: 9, smoothing: 0.5, floatRelError: 5.9207e-6};

	let success = true;

	let graph = createGraph(options);

	context = graph.context;
	analyser = graph.analyser;

	let smoothedFloatResult = new Float32Array(analyser.frequencyBinCount);
	smoothedFloatResult.fill(0);

	// Stop after one analyser frame to get the initial FFT
	let suspendFrame = analyser.fftSize;
	context.suspend(suspendFrame / sampleRate)
	.then(function() {
	let timeData = new Float32Array(analyser.fftSize);
	let freqData = new Float32Array(analyser.frequencyBinCount);
	analyser.getFloatTimeDomainData(timeData);
	analyser.getFloatFrequencyData(freqData);

	let expectedFreq = computeFFTMagnitude(timeData, options.order);
	smoothFFT(smoothedFloatResult, expectedFreq, options.smoothing);

	let message = 'First ' + analyser.fftSize +
	'-point FFT at frame ' + (context.currentTime * sampleRate);
	let comparison = compareFloatFreq(
	message, freqData, smoothedFloatResult.map(linearToDb),
	should, options);
	success = success && comparison.success;

	// Test the byte frequency data.
	let byteFreqData = new Uint8Array(analyser.frequencyBinCount);
	analyser.getByteFrequencyData(byteFreqData);

	// Convert the expected float frequency data to byte data.
	let expectedByteData = convertFloatToByte(
	smoothedFloatResult.map(linearToDb), analyser.minDecibels,
	analyser.maxDecibels);

	should(byteFreqData, analyser.fftSize + '-point byte FFT')
	.beCloseToArray(expectedByteData, 0);

	})
	.then(context.resume.bind(context));

	// Skip an analyser frame and grab another to verify that the smoothing
	// is done correctly.
	suspendFrame += 2 * analyser.fftSize;
	context.suspend(suspendFrame / sampleRate)
	.then(function() {
	let timeData = new Float32Array(analyser.fftSize);
	let freqDataInDb = new Float32Array(analyser.frequencyBinCount);

	// Grab the time domain and frequency domain data
	analyser.getFloatTimeDomainData(timeData);
	analyser.getFloatFrequencyData(freqDataInDb);

	let newFreqData = computeFFTMagnitude(timeData, options.order);
	// Smooth the data together

	smoothFFT(smoothedFloatResult, newFreqData, options.smoothing);
	let message = 'Smoothed ' + analyser.fftSize +
	'-point FFT at frame ' + (context.currentTime * sampleRate);
	let comparison = compareFloatFreq(
	message, freqDataInDb, smoothedFloatResult.map(linearToDb),
	should, {
	order: options.order,
	smoothing: options.smoothing,
	floatRelError: 2.5332e-5
	});
	success = success && comparison.success;

	// Test the byte frequency data.
	let byteFreqData = new Uint8Array(analyser.frequencyBinCount);
	analyser.getByteFrequencyData(byteFreqData);

	// Convert the expected float frequency data to byte data.
	let expectedByteData = convertFloatToByte(
	smoothedFloatResult.map(linearToDb), analyser.minDecibels,
	analyser.maxDecibels);

	should(byteFreqData, analyser.fftSize + '-point byte FFT')
	.beCloseToArray(expectedByteData, 0);

	})
	.then(context.resume.bind(context));

	context.startRendering().then(() => task.done());
	});

	audit.run();
	</script>
	</body>
	</html>