audio-lena

Lena test audio fixture for audio decoders/encoders. The audio equivalent of the Lena test image.

Mono, 44100 Hz, ~12s. Noisy background, visible spectral peaks with harmonics, pitch variation. Good for codec testing, decoding, encoding, DSP, filtering.

Parameter	Value
samplesCount	541184
duration	12.27s
numberOfChannels	1
sampleRate	44100
artist	Lena Stolze
track	Oh lad le
album	Das schreckliche Mädchen
year	2014

Formats

Format	Size	MIME
wav	1057 KB	audio/wav
mp3	193 KB	audio/mpeg
ogg	109 KB	audio/ogg
flac	473 KB	audio/flac
opus	111 KB	audio/opus
aac	108 KB	audio/aac
m4a	243 KB	audio/mp4
aiff	1059 KB	audio/aiff
webm	161 KB	audio/webm
caf	1058 KB	audio/x-caf
raw	2114 KB	float32 samples

Usage

npm i audio-lena

// ArrayBuffer with encoded audio
import wav from 'audio-lena/wav'
import mp3 from 'audio-lena/mp3'
import flac from 'audio-lena/flac'

// Base64 string
import mp3Base64 from 'audio-lena/mp3-base64'

// Data URI
import oggDatauri from 'audio-lena/ogg-datauri'
let audio = new Audio(oggDatauri)

// Raw float32 samples
import raw from 'audio-lena/raw'
let samples = new Float32Array(raw)

// File URL (works in Node and browser)
import lena from 'audio-lena'
let url = lena.url('flac')

// Node: file path
import { fileURLToPath } from 'node:url'
let path = fileURLToPath(lena.url('flac'))

API

import lena from 'audio-lena'

Metadata and helpers.

Property	Value
lena.duration	12.27
lena.samplesCount	541184
lena.channels	1
lena.numberOfChannels	1
lena.sampleRate	44100
lena.formats	['wav', 'mp3', 'ogg', ...]
lena.url(format)	URL to fixture file

import buf from 'audio-lena/<format>'

Returns ArrayBuffer with encoded audio data.

Formats: wav, mp3, ogg, flac, opus, aac, m4a, aiff, webm, caf, raw.

import b64 from 'audio-lena/<format>-base64'

Returns base64-encoded string.

import uri from 'audio-lena/<format>-datauri'

Returns data-URI string (data:<mime>;base64,...).

Extra fixtures

Additional encoding variants are included for decoder compatibility testing. No JS modules — access via file path.

Root variants (encoded with ffmpeg/sox):

File	Encoding
lena-24.aiff	AIFF 24-bit PCM
lena-32.aiff	AIFF 32-bit PCM
lena-ulaw.aiff	AIFF µ-law
lena-alaw.aiff	AIFF A-law
lena-alaw.caf	CAF A-law
lena-f32.caf	CAF 32-bit float
lena-vorbis.webm	WebM Vorbis

audacity/ (exported from Audacity):

File	Encoding
lena-24.aiff	AIFF 24-bit PCM
lena-24-dwvw.aiff	AIFF 24-bit DWVW compressed
lena-32.wav	WAV 32-bit float
lena-64.aiff	AIFF 64-bit float
lena-u.aiff	AIFF µ-law
lena-a.aiff	AIFF A-law
lena-gsm.aiff	AIFF GSM 6.10 compressed
lena-ima-adpcm.aiff	AIFF IMA-ADPCM

logic/ (exported from Logic Pro):

File	Encoding
lena-24.aif	AIFF 24-bit PCM
lena-24.wav	WAV 24-bit PCM
lena-32.aif	AIFF 32-bit float

Same audio encoded by different tools — useful for testing decoder tolerance across encoder implementations.

Generating

To regenerate modules from binary fixtures:

node generate.js

To add a format, drop lena.<ext> into the root, add an entry to generate.js, and run it.

Reference

• Lenna in wiki.
• Lena.mp3 original.
• Lena test image.

Related

• silent-mp3-datauri