stream-chat-react/dist/components/MediaRecorder/transcode/audioProcessing.js

React components to create chat conversations or livestream style chat

import { readFileAsArrayBuffer } from '../../ReactFileUtilities';
/**
 * In the context of resampling audio data, AudioContext is used to decode the input audio file into an AudioBuffer,
 * which is a fundamental data structure representing audio data.
 * @param file
 */
export const toAudioBuffer = async (file) => {
    const audioCtx = new AudioContext();
    const arrayBuffer = await readFileAsArrayBuffer(file);
    const decodedData = await audioCtx.decodeAudioData(arrayBuffer);
    if (audioCtx.state !== 'closed')
        await audioCtx.close();
    return decodedData;
};
/**
 * OfflineAudioContext is a specialized type of AudioContext that does not render audio in real-time and is used for offline audio processing tasks.
 * It allows performing audio processing and rendering without actually playing the audio through speakers or outputting it to a destination.
 * In the context of resampling audio data, OfflineAudioContext is used to resample the decoded AudioBuffer from a file to the desired sample rate.
 * It provides more flexibility and control over audio processing, as it can operate at different sample rates and durations compared to real-time audio contexts.
 * @param audioBuffer
 * @param sampleRate
 */
export const renderAudio = async (audioBuffer, sampleRate) => {
    const offlineAudioCtx = new OfflineAudioContext(audioBuffer.numberOfChannels, audioBuffer.duration * sampleRate, sampleRate);
    const source = offlineAudioCtx.createBufferSource();
    source.buffer = audioBuffer;
    source.connect(offlineAudioCtx.destination);
    source.start();
    return await offlineAudioCtx.startRendering();
};