Shivam Mishra
2024-10-02 13:06:30 +05:30
committed by GitHub
parent e0bf2bd9d4
commit 42f6621afb
661 changed files with 15939 additions and 31194 deletions

View File

@@ -1,14 +1,77 @@
import lamejs from 'lamejs';
import lamejs from '@breezystack/lamejs';
const writeString = (view, offset, string) => {
for (let i = 0; i < string.length; i++) {
view.setUint8(offset + i, string.charCodeAt(i));
}
};
const bufferToWav = async (buffer, numChannels, sampleRate) => {
const length = buffer.length * numChannels * 2;
const wav = new ArrayBuffer(44 + length);
const view = new DataView(wav);
// WAV Header
writeString(view, 0, 'RIFF');
view.setUint32(4, 36 + length, true);
writeString(view, 8, 'WAVE');
writeString(view, 12, 'fmt ');
view.setUint32(16, 16, true);
view.setUint16(20, 1, true);
view.setUint16(22, numChannels, true);
view.setUint32(24, sampleRate, true);
view.setUint32(28, sampleRate * numChannels * 2, true);
view.setUint16(32, numChannels * 2, true);
view.setUint16(34, 16, true);
writeString(view, 36, 'data');
view.setUint32(40, length, true);
// WAV Data
const offset = 44;
for (let i = 0; i < buffer.length; i++) {
for (let channel = 0; channel < numChannels; channel++) {
const sample = Math.max(
-1,
Math.min(1, buffer.getChannelData(channel)[i])
);
view.setInt16(
offset + (i * numChannels + channel) * 2,
sample * 0x7fff,
true
);
}
}
return new Blob([wav], { type: 'audio/wav' });
};
const decodeAudioData = async audioBlob => {
const audioContext = new (window.AudioContext || window.webkitAudioContext)();
const arrayBuffer = await audioBlob.arrayBuffer();
const audioData = await audioContext.decodeAudioData(arrayBuffer);
return audioData;
};
export const convertToWav = async audioBlob => {
const audioBuffer = await decodeAudioData(audioBlob);
return bufferToWav(
audioBuffer,
audioBuffer.numberOfChannels,
audioBuffer.sampleRate
);
};
/**
* Encodes a mono channel audio stream to MP3 format.
* Encodes audio samples to MP3 format.
* @param {number} channels - Number of audio channels.
* @param {number} sampleRate - Sample rate in Hz.
* @param {Int16Array} samples - Audio samples to be encoded.
* @param {number} bitrate - MP3 bitrate (default: 128)
* @returns {Blob} - The MP3 encoded audio as a Blob.
*/
export const encodeToMP3 = (channels, sampleRate, samples) => {
export const encodeToMP3 = (channels, sampleRate, samples, bitrate = 128) => {
const outputBuffer = [];
const encoder = new lamejs.Mp3Encoder(channels, sampleRate, 128);
const encoder = new lamejs.Mp3Encoder(channels, sampleRate, bitrate);
const maxSamplesPerFrame = 1152;
for (let offset = 0; offset < samples.length; offset += maxSamplesPerFrame) {
@@ -30,24 +93,51 @@ export const encodeToMP3 = (channels, sampleRate, samples) => {
};
/**
* Converts a WAV audio Blob to an MP3 format Blob.
* @param {Blob} blob - The audio data in WAV format as a Blob.
* Converts an audio Blob to an MP3 format Blob.
* @param {Blob} audioBlob - The audio data as a Blob.
* @param {number} bitrate - MP3 bitrate (default: 128)
* @returns {Promise<Blob>} - A Blob containing the MP3 encoded audio.
*/
export const convertWavToMp3 = async blob => {
export const convertToMp3 = async (audioBlob, bitrate = 128) => {
try {
const audioBuffer = await blob.arrayBuffer();
const wavHeader = lamejs.WavHeader.readHeader(new DataView(audioBuffer));
const audioBuffer = await decodeAudioData(audioBlob);
const samples = new Int16Array(
audioBuffer,
wavHeader.dataOffset,
wavHeader.dataLen / 2
audioBuffer.length * audioBuffer.numberOfChannels
);
let offset = 0;
for (let i = 0; i < audioBuffer.length; i += 1) {
for (
let channel = 0;
channel < audioBuffer.numberOfChannels;
channel += 1
) {
const sample = Math.max(
-1,
Math.min(1, audioBuffer.getChannelData(channel)[i])
);
samples[offset] = sample < 0 ? sample * 0x8000 : sample * 0x7fff;
offset += 1;
}
}
return encodeToMP3(
audioBuffer.numberOfChannels,
audioBuffer.sampleRate,
samples,
bitrate
);
return encodeToMP3(wavHeader.channels, wavHeader.sampleRate, samples);
} catch (error) {
// eslint-disable-next-line
console.log('Failed to convert WAV to MP3:', error);
throw new Error('Conversion from WAV to MP3 failed.');
throw new Error('Conversion to MP3 failed.');
}
};
export const convertAudio = async (inputBlob, outputFormat, bitrate = 128) => {
let audio;
if (outputFormat === 'audio/wav') {
audio = await convertToWav(inputBlob);
} else if (outputFormat === 'audio/mp3') {
audio = await convertToMp3(inputBlob, bitrate);
} else {
throw new Error('Unsupported output format');
}
return audio;
};