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Diffstat (limited to 'dom/media/webaudio/test/test_mediaElementAudioSourceNodeFidelity.html')
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diff --git a/dom/media/webaudio/test/test_mediaElementAudioSourceNodeFidelity.html b/dom/media/webaudio/test/test_mediaElementAudioSourceNodeFidelity.html new file mode 100644 index 000000000..8d3b0ed46 --- /dev/null +++ b/dom/media/webaudio/test/test_mediaElementAudioSourceNodeFidelity.html @@ -0,0 +1,128 @@ +<!DOCTYPE HTML> +<html> +<meta charset="utf-8"> +<head> + <title>Test MediaStreamAudioSourceNode doesn't get data from cross-origin media resources</title> + <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script> + <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" /> +</head> +<body> +<pre id="test"> +<script class="testbody" type="text/javascript"> +SimpleTest.waitForExplicitFinish(); + +function binIndexForFrequency(frequency, analyser) { + return 1 + Math.round(frequency * + analyser.fftSize / + analyser.context.sampleRate); +} + +function debugCanvas(analyser) { + var cvs = document.createElement("canvas"); + document.body.appendChild(cvs); + + // Easy: 1px per bin + cvs.width = analyser.frequencyBinCount; + cvs.height = 256; + cvs.style.border = "1px solid red"; + + var c = cvs.getContext('2d'); + var buf = new Uint8Array(analyser.frequencyBinCount); + + function render() { + c.clearRect(0, 0, cvs.width, cvs.height); + analyser.getByteFrequencyData(buf); + for (var i = 0; i < buf.length; i++) { + c.fillRect(i, (256 - (buf[i])), 1, 256); + } + requestAnimationFrame(render); + } + requestAnimationFrame(render); +} + + +function checkFrequency(an) { + an.getFloatFrequencyData(frequencyArray); + // We should have no energy when checking the data largely outside the index + // for 440Hz (the frequency of the sine wave), start checking an octave above, + // the Opus compression can add some harmonics to the pure since wave. + var index = binIndexForFrequency(880, an); + var underTreshold = true; + for (var i = index; i < frequencyArray.length; i++) { + // Let some slack, there might be some noise here because of int -> float + // conversion or the Opus encoding. + if (frequencyArray[i] > an.minDecibels + 40) { + return false; + } + } + + // On the other hand, we should find a peak at 440Hz. Our sine wave is not + // attenuated, we're expecting the peak to reach 0dBFs. + index = binIndexForFrequency(440, an); + info("energy at 440: " + frequencyArray[index] + ", threshold " + (an.maxDecibels - 10)); + if (frequencyArray[index] < (an.maxDecibels - 10)) { + return false; + } + + return true; +} + +var audioElement = new Audio(); +audioElement.src = 'sine-440-10s.opus' +audioElement.loop = true; +var ac = new AudioContext(); +var mediaElementSource = ac.createMediaElementSource(audioElement); +var an = ac.createAnalyser(); +frequencyArray = new Float32Array(an.frequencyBinCount); + +// Uncomment this to check what the analyser is doing. +// debugCanvas(an); + +mediaElementSource.connect(an) + +audioElement.play(); +// We want to check the we have the expected audio for at least two loop of +// the HTMLMediaElement, piped into an AudioContext. The file is ten seconds, +// and we use the default FFT size. +var lastCurrentTime = 0; +var loopCount = 0; +audioElement.onplaying = function() { + audioElement.ontimeupdate = function() { + // We don't run the analysis when close to loop point or at the + // beginning, since looping is not seamless, there could be an + // unpredictable amount of silence + var rv = checkFrequency(an); + info("currentTime: " + audioElement.currentTime); + if (audioElement.currentTime < 4 || + audioElement.currentTIme > 8){ + return; + } + if (!rv) { + ok(false, "Found unexpected noise during analysis."); + audioElement.ontimeupdate = null; + audioElement.onplaying = null; + ac.close(); + audioElement.src = ''; + SimpleTest.finish() + return; + } + ok(true, "Found correct audio signal during analysis"); + info(lastCurrentTime + " " + audioElement.currentTime); + if (lastCurrentTime > audioElement.currentTime) { + info("loopCount: " + loopCount); + if (loopCount > 1) { + audioElement.ontimeupdate = null; + audioElement.onplaying = null; + ac.close(); + audioElement.src = ''; + SimpleTest.finish(); + } + lastCurrentTime = audioElement.currentTime; + loopCount++; + } else { + lastCurrentTime = audioElement.currentTime; + } + } +} + +</script> |