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| author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 17:32:43 +0000 |
|---|---|---|
| committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 17:32:43 +0000 |
| commit | 6bf0a5cb5034a7e684dcc3500e841785237ce2dd (patch) | |
| tree | a68f146d7fa01f0134297619fbe7e33db084e0aa /dom/media/webaudio/test/test_convolverNodeNormalization.html | |
| parent | Initial commit. (diff) | |
| download | thunderbird-6bf0a5cb5034a7e684dcc3500e841785237ce2dd.tar.xz thunderbird-6bf0a5cb5034a7e684dcc3500e841785237ce2dd.zip | |
Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'dom/media/webaudio/test/test_convolverNodeNormalization.html')
| -rw-r--r-- | dom/media/webaudio/test/test_convolverNodeNormalization.html | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/dom/media/webaudio/test/test_convolverNodeNormalization.html b/dom/media/webaudio/test/test_convolverNodeNormalization.html new file mode 100644 index 0000000000..24cb7d1670 --- /dev/null +++ b/dom/media/webaudio/test/test_convolverNodeNormalization.html @@ -0,0 +1,83 @@ +<!DOCTYPE html> +<title>Test normalization of convolution buffers</title> +<script src="/resources/testharness.js"></script> +<script src="/resources/testharnessreport.js"></script> +<script> +// Constants from +// https://www.w3.org/TR/2015/WD-webaudio-20151208/#widl-ConvolverNode-normalize +const GainCalibration = 0.00125; +const GainCalibrationSampleRate = 44100; + +const sampleRate = GainCalibrationSampleRate; +const LENGTH = 12800; +// tolerate 16-bit math. +const EPSILON = 1.0 / Math.pow(2, 15); + +function test_normalization_via_response_concat(delayIndex) +{ + var context = new OfflineAudioContext(1, LENGTH, sampleRate); + + var impulse = context.createBuffer(1, 1, sampleRate); + impulse.getChannelData(0)[0] = 1.0; + var source = context.createBufferSource(); + source.buffer = impulse; + source.start(0); + + // Construct a set of adjacent responses in such a way that, when each is + // convolved with the impulse, they can be merged to produce a constant. + + // The 5/4 ratio provides a range of lengths with different offsets within + // blocks. + var i = 0; + for (var responseEnd = 1; + i < LENGTH; + responseEnd = Math.floor((5 * responseEnd) / 4) + 1) { + var responseBuffer = context.createBuffer(1, responseEnd, sampleRate); + var response = responseBuffer.getChannelData(0); + var responseStart = i; + // The values in the response should be normalized, and so the output + // should not be dependent on the value. Pick a changing value to test + // this. + var value = responseStart + 1; + for (; i < responseEnd; ++i) { + response[i] = value; + } + var convolver = context.createConvolver(); + convolver.normalize = true; + convolver.buffer = responseBuffer; + convolver.connect(context.destination); + // Undo the normalization calibration by scaling the impulse so as to + // expect unit pulse output from the convolver. + var gain = context.createGain(); + gain.gain.value = + Math.sqrt((responseEnd - responseStart) / responseEnd) / GainCalibration; + gain.connect(convolver); + source.connect(gain); + } + + return context.startRendering(). + then((buffer) => { + var output = buffer.getChannelData(0); + var max = output[0]; + var maxIndex = 0; + var min = max; + var minIndex = 0; + for (var i = 1; i < buffer.length; ++i) { + if (output[i] > max) { + max = output[i]; + maxIndex = i; + } else if (output[i] < min) { + min = output[i]; + minIndex = i; + } + } + assert_approx_equals(output[maxIndex], 1.0, EPSILON, + "max output at " + maxIndex); + assert_approx_equals(output[minIndex], 1.0, EPSILON, + "min output at " + minIndex); + }); +} + +promise_test(test_normalization_via_response_concat, + "via response concatenation"); +</script> |