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