chromium/src/third_party/blink/web_tests/webaudio/AudioParam/audioparam-negative-exponentialRamp.html - manifest_repos/chromium_src - Git at Google

 <!DOCTYPE html>
 <html>
   <head>
     <title>
       Test Negative AudioParam.exponentialRampToValueAtTime
     </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>
   </head>
   <body>
     <script id="layout-test-code">
       let sampleRate = 48000;

       let audit = Audit.createTaskRunner();

       audit.define('both negative values', (task, should) => {
         let renderDuration = 0.125;

         // Create context with two channels.  Channel 0 contains the
         // positive-valued exponential and channel 1 contains the
         // negative-valued exponential.  We'll compare the two channels to
         // verify that they're the same, as they should be.
         let context =
             new OfflineAudioContext(2, renderDuration * sampleRate, sampleRate);
         let source = context.createBufferSource();
         source.buffer = createConstantBuffer(context, 1, 1);
         source.loop = true;

         // Gain node gp is for the positive-valued exponential ramp, and gn is
         // for the negative-valued exponential ramp.
         let gp = context.createGain();
         let gn = context.createGain();
         let merger = context.createChannelMerger(2);

         source.connect(gp).connect(merger, 0, 0);
         source.connect(gn).connect(merger, 0, 1);
         merger.connect(context.destination);

         gp.gain.setValueAtTime(1, 0);
         gp.gain.exponentialRampToValueAtTime(2, renderDuration);

         gn.gain.setValueAtTime(-1, 0);
         gn.gain.exponentialRampToValueAtTime(-2, renderDuration);

         source.start();

         context.startRendering()
             .then(function(resultBuffer) {
               // Verify that channels have the same values, except for the sign.
               let expected = resultBuffer.getChannelData(0);
               let actual = resultBuffer.getChannelData(1);
               let inverted = expected.map(sample => -sample);

               should(actual, 'Negative exponential ramp from -1 to -2')
                   .beEqualToArray(inverted);
             })
             .then(() => task.done());
       });

       audit.define('negative-end', (task, should) => {
         // Positive start value and negative end value should just do nothing.
         let renderDuration = 0.125;
         let context =
             new OfflineAudioContext(1, renderDuration * sampleRate, sampleRate);
         let source = context.createBufferSource();
         source.buffer = createConstantBuffer(context, 1, 1);
         source.loop = true;

         // Gain node gp is for the positive-valued exponential ramp, and gn is
         // for the negative-valued exponential ramp.
         let g = context.createGain();

         g.gain.setValueAtTime(2, 0);
         g.gain.exponentialRampToValueAtTime(-1, renderDuration);

         source.connect(g).connect(context.destination);

         source.start();

         context.startRendering()
             .then(function(resultBuffer) {
               let actual = resultBuffer.getChannelData(0);

               should(actual, 'Exponential ramp from 2 to -1')
                   .beConstantValueOf(2);
             })
             .then(() => task.done());
       });

       audit.define('positive-end', (task, should) => {
         // Positive start value and negative end value should just do nothing.
         let renderDuration = 0.125;
         let context =
             new OfflineAudioContext(1, renderDuration * sampleRate, sampleRate);
         let source = context.createBufferSource();
         source.buffer = createConstantBuffer(context, 1, 1);
         source.loop = true;

         let g = context.createGain();

         g.gain.setValueAtTime(-1, 0);
         g.gain.exponentialRampToValueAtTime(1, renderDuration);

         source.connect(g).connect(context.destination);
         source.start();

         context.startRendering()
             .then(function(resultBuffer) {
               let actual = resultBuffer.getChannelData(0);

               should(actual, 'Exponential ramp from -1 to 1')
                   .beConstantValueOf(-1);
             })
             .then(() => task.done());
       });

       audit.define('propagate', (task, should) => {
         // Test propagation of ramp if the exponential ramp start and end values
         // have opposite sign.
         let renderDuration = 0.125;
         let linearRampEnd = renderDuration / 4;
         let exponentialRampEnd = renderDuration / 2;

         let context =
             new OfflineAudioContext(1, renderDuration * sampleRate, sampleRate);
         let source = context.createBufferSource();
         source.buffer = createConstantBuffer(context, 1, 1);
         source.loop = true;

         let g = context.createGain();

         g.gain.setValueAtTime(2, 0);
         g.gain.linearRampToValueAtTime(-1, linearRampEnd);
         g.gain.exponentialRampToValueAtTime(1, exponentialRampEnd);

         source.connect(g).connect(context.destination);
         source.start();

         context.startRendering()
             .then(function(resultBuffer) {
               let actual = resultBuffer.getChannelData(0);

               // Since the start value of the exponential ramp is -1 and the end
               // value is 1, the ramp should just propagate -1 to the end of
               // the exponential ramp, and then propagate the exponential ramp
               // value "forever" afterwards.
               const linearEndFrame = Math.ceil(linearRampEnd * sampleRate);
               const expoEndFrame = Math.ceil(exponentialRampEnd * sampleRate);
               should(
                   actual.slice(linearEndFrame, expoEndFrame),
                   'Exponential ramp from -1 to 1 after the end of the linear ramp')
                   .beConstantValueOf(-1);
               should(
                   actual.slice(expoEndFrame),
                   'Exponential ramp after end of ramp')
                   .beConstantValueOf(1);
             })
             .then(() => task.done());
       });

       audit.run();
     </script>
   </body>
 </html>
	<!DOCTYPE html>
	<html>
	<head>
	<title>
	Test Negative AudioParam.exponentialRampToValueAtTime
	</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>
	</head>
	<body>
	<script id="layout-test-code">
	let sampleRate = 48000;

	let audit = Audit.createTaskRunner();

	audit.define('both negative values', (task, should) => {
	let renderDuration = 0.125;

	// Create context with two channels. Channel 0 contains the
	// positive-valued exponential and channel 1 contains the
	// negative-valued exponential. We'll compare the two channels to
	// verify that they're the same, as they should be.
	let context =
	new OfflineAudioContext(2, renderDuration * sampleRate, sampleRate);
	let source = context.createBufferSource();
	source.buffer = createConstantBuffer(context, 1, 1);
	source.loop = true;

	// Gain node gp is for the positive-valued exponential ramp, and gn is
	// for the negative-valued exponential ramp.
	let gp = context.createGain();
	let gn = context.createGain();
	let merger = context.createChannelMerger(2);

	source.connect(gp).connect(merger, 0, 0);
	source.connect(gn).connect(merger, 0, 1);
	merger.connect(context.destination);

	gp.gain.setValueAtTime(1, 0);
	gp.gain.exponentialRampToValueAtTime(2, renderDuration);

	gn.gain.setValueAtTime(-1, 0);
	gn.gain.exponentialRampToValueAtTime(-2, renderDuration);

	source.start();

	context.startRendering()
	.then(function(resultBuffer) {
	// Verify that channels have the same values, except for the sign.
	let expected = resultBuffer.getChannelData(0);
	let actual = resultBuffer.getChannelData(1);
	let inverted = expected.map(sample => -sample);

	should(actual, 'Negative exponential ramp from -1 to -2')
	.beEqualToArray(inverted);
	})
	.then(() => task.done());
	});

	audit.define('negative-end', (task, should) => {
	// Positive start value and negative end value should just do nothing.
	let renderDuration = 0.125;
	let context =
	new OfflineAudioContext(1, renderDuration * sampleRate, sampleRate);
	let source = context.createBufferSource();
	source.buffer = createConstantBuffer(context, 1, 1);
	source.loop = true;

	// Gain node gp is for the positive-valued exponential ramp, and gn is
	// for the negative-valued exponential ramp.
	let g = context.createGain();

	g.gain.setValueAtTime(2, 0);
	g.gain.exponentialRampToValueAtTime(-1, renderDuration);

	source.connect(g).connect(context.destination);

	source.start();

	context.startRendering()
	.then(function(resultBuffer) {
	let actual = resultBuffer.getChannelData(0);

	should(actual, 'Exponential ramp from 2 to -1')
	.beConstantValueOf(2);
	})
	.then(() => task.done());
	});

	audit.define('positive-end', (task, should) => {
	// Positive start value and negative end value should just do nothing.
	let renderDuration = 0.125;
	let context =
	new OfflineAudioContext(1, renderDuration * sampleRate, sampleRate);
	let source = context.createBufferSource();
	source.buffer = createConstantBuffer(context, 1, 1);
	source.loop = true;

	let g = context.createGain();

	g.gain.setValueAtTime(-1, 0);
	g.gain.exponentialRampToValueAtTime(1, renderDuration);

	source.connect(g).connect(context.destination);
	source.start();

	context.startRendering()
	.then(function(resultBuffer) {
	let actual = resultBuffer.getChannelData(0);

	should(actual, 'Exponential ramp from -1 to 1')
	.beConstantValueOf(-1);
	})
	.then(() => task.done());
	});

	audit.define('propagate', (task, should) => {
	// Test propagation of ramp if the exponential ramp start and end values
	// have opposite sign.
	let renderDuration = 0.125;
	let linearRampEnd = renderDuration / 4;
	let exponentialRampEnd = renderDuration / 2;

	let context =
	new OfflineAudioContext(1, renderDuration * sampleRate, sampleRate);
	let source = context.createBufferSource();
	source.buffer = createConstantBuffer(context, 1, 1);
	source.loop = true;

	let g = context.createGain();

	g.gain.setValueAtTime(2, 0);
	g.gain.linearRampToValueAtTime(-1, linearRampEnd);
	g.gain.exponentialRampToValueAtTime(1, exponentialRampEnd);

	source.connect(g).connect(context.destination);
	source.start();

	context.startRendering()
	.then(function(resultBuffer) {
	let actual = resultBuffer.getChannelData(0);

	// Since the start value of the exponential ramp is -1 and the end
	// value is 1, the ramp should just propagate -1 to the end of
	// the exponential ramp, and then propagate the exponential ramp
	// value "forever" afterwards.
	const linearEndFrame = Math.ceil(linearRampEnd * sampleRate);
	const expoEndFrame = Math.ceil(exponentialRampEnd * sampleRate);
	should(
	actual.slice(linearEndFrame, expoEndFrame),
	'Exponential ramp from -1 to 1 after the end of the linear ramp')
	.beConstantValueOf(-1);
	should(
	actual.slice(expoEndFrame),
	'Exponential ramp after end of ramp')
	.beConstantValueOf(1);
	})
	.then(() => task.done());
	});

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