@audio/mp3-encode

Encode PCM audio samples to MP3 format. WASM (libmp3lame via wasm-media-encoders) — works in both node and browser.

import mp3 from '@audio/mp3-encode';

const encoder = await mp3({ sampleRate: 44100, channels: 1, bitrate: 128 });
const chunk = encoder.encode(channelData); // → Uint8Array (MP3 frames)
const tail = encoder.flush();              // → Uint8Array (remaining)
// concatenate chunk + tail for complete MP3 file

Options

| Option | Default | Description | |--------|---------|-------------| | sampleRate | — | Sample rate (required) | | channels | 2 | 1 (mono) or 2 (stereo) | | bitrate | 128 | CBR bitrate in kbps | | quality | — | VBR quality 0–9 (0=best). If set, overrides bitrate. |

Streaming

const encoder = await mp3({ sampleRate: 44100, channels: 1, bitrate: 192 });
const a = encoder.encode(chunk1); // → Uint8Array
const b = encoder.encode(chunk2); // → Uint8Array
const c = encoder.flush();        // → Uint8Array
// complete MP3 = concat(a, b, c)
encoder.free();

License

MIT

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