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@AppleHolic
Created December 3, 2020 09:48
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Wave file writing codes in several language (javascript, kotlin, +python)
export default class {
constructor (options) {
this.bufferSize = options.bufferSize || 4096
this.sampleRate = options.sampleRate
this.samples = options.samples
}
getData () {
this._joinSamples()
let buffer = new ArrayBuffer(44 + this.samples.length * 2)
let view = new DataView(buffer)
this._writeString(view, 0, 'RIFF') // RIFF identifier
view.setUint32(4, 36 + this.samples.length * 2, true) // RIFF chunk length
this._writeString(view, 8, 'WAVE') // RIFF type
this._writeString(view, 12, 'fmt ') // format chunk identifier
view.setUint32(16, 16, true) // format chunk length
view.setUint16(20, 1, true) // sample format (raw)
view.setUint16(22, 1, true) // channel count
view.setUint32(24, this.sampleRate, true) // sample rate
view.setUint32(28, this.sampleRate * 4, true) // byte rate (sample rate * block align)
view.setUint16(32, 4, true) // block align (channel count * bytes per sample)
view.setUint16(34, 16, true) // bits per sample
this._writeString(view, 36, 'data') // data chunk identifier
view.setUint32(40, this.samples.length * 2, true) // data chunk length
this._floatTo16BitPCM(view, 44, this.samples)
return new Blob([view], {type: 'audio/wav'})
}
_floatTo16BitPCM (output, offset, input) {
for (let i = 0; i < input.length; i++, offset += 2) {
let s = Math.max(-1, Math.min(1, input[i]))
output.setInt16(offset, s < 0 ? s * 0x8000 : s * 0x7FFF, true)
}
}
_joinSamples () {
let recordLength = this.samples.length * this.bufferSize
let joinedSamples = new Float64Array(recordLength)
let offset = 0
for (let i = 0; i < this.samples.length; i++) {
let sample = this.samples[i]
joinedSamples.set(sample, offset)
offset += sample.length
}
this.samples = joinedSamples
}
_writeString (view, offset, string) {
for (let i = 0; i < string.length; i++) {
view.setUint8(offset + i, string.charCodeAt(i))
}
}
}
@anseldu
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anseldu commented Oct 18, 2021

There is a issue at here:
line 47: joinedSamples.set(sample, offset)
issue like this:
Uncaught TypeError: invalid_argument
at Float64Array.set ()
why?

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