23 lines
689 B
JavaScript
23 lines
689 B
JavaScript
let toneLengthSeconds = 1;
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// Create a buffer with multiple channels.
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// The signal frequency in each channel is the multiple of that in the first
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// channel.
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function createToneBuffer(context, frequency, duration, numberOfChannels) {
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let sampleRate = context.sampleRate;
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let sampleFrameLength = duration * sampleRate;
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let audioBuffer =
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context.createBuffer(numberOfChannels, sampleFrameLength, sampleRate);
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let n = audioBuffer.length;
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for (let k = 0; k < numberOfChannels; ++k) {
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let data = audioBuffer.getChannelData(k);
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for (let i = 0; i < n; ++i)
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data[i] = Math.sin(frequency * (k + 1) * 2.0 * Math.PI * i / sampleRate);
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}
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return audioBuffer;
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}
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