detectAudioFormat

Detects the audio container format from magic bytes in the buffer.

function detectAudioFormat(buffer): DetectedAudioFormat | null;

Defined in: src/utils/audioFormat.ts:117

Detects the audio container format from magic bytes in the buffer.

Parameters

Parameter	Type	Description
`buffer`	`ArrayBuffer`	The audio data buffer to inspect. Must be at least MIN_SNIFF_BYTES bytes for reliable detection.

Returns

DetectedAudioFormat | null

The detected format, or null if the format cannot be determined.

Remarks

Inspects the first MIN_SNIFF_BYTES bytes of the given buffer to identify the audio container format. The detection order is chosen to minimize false positives: unambiguous signatures (WAV, OGG, FLAC, EBML) are checked first, followed by more ambiguous sync-word-based formats (MP3, AAC).

Returns null when:

The buffer has fewer than MIN_SNIFF_BYTES bytes
No known magic bytes match (likely raw PCM or an unsupported format)

Example

// WAV detection
const wavHeader = new Uint8Array([
  0x52, 0x49, 0x46, 0x46, // "RIFF"
  0x00, 0x00, 0x00, 0x00, // file size placeholder
  0x57, 0x41, 0x56, 0x45, // "WAVE"
]);
detectAudioFormat(wavHeader.buffer); // => 'wav'

// Raw PCM (no magic bytes)
const pcm = new Uint8Array(64).buffer;
detectAudioFormat(pcm); // => null

See

DetectedAudioFormat for the set of possible return values
extractHeader for extracting the header once the format is known