@audio/encode-qoa

Encode PCM audio samples to QOA (Quite OK Audio) format. Pure JS, ~3.2 bits/sample fixed-quality lossy — works in both node and browser.

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

const encoder = await qoa({ sampleRate: 44100 });
encoder.encode(channelData);  // → Uint8Array (buffered)
const bytes = encoder.flush(); // → Uint8Array (complete QOA file)
encoder.free();

Options

| Option | Default | Description | |--------|---------|-------------| | sampleRate | — | Input sample rate in Hz (required) |

QOA is a fixed-quality lossy codec (~3.2 bits/sample, 256-sample slices). Channel count is inferred from the data passed to encode(). There are no bitrate or quality knobs.

Streaming

QOA requires the total sample count in its file header, so all chunks are buffered internally and the complete file is returned on flush(). Each encode() call returns an empty Uint8Array.

const encoder = await qoa({ sampleRate: 44100 });
encoder.encode(chunk1); // buffered
encoder.encode(chunk2); // buffered
const file = encoder.flush(); // → complete QOA file
encoder.free();

Streaming output

Frames encode as 5120 samples fill, the LMS state carried across them (byte-identical to qoa-format's whole-file encoder); whole-file mode keeps the encoded frames, not the PCM. stream: true emits them as they encode under a samples: 0 header (QOA's streaming mode); after flush(), head() returns the 8-byte header with the sample count. With frames (the exact length, known upfront) the header goes out exact and head() has nothing to add.

License

MIT

ॐ