CL-RemiAudio

CL-RemiAudio is a collection of high-performance audio format I/O routines, codecs, processors/effects, and other audio-related code written entirely in Common Lisp. It is split up into multiple ASDF systems for ease of use.

There is also a version for the Crystal programming language if you’d like available here.

• Official Homepage and Source Repository

Features

A list of supported features. Unless specified, the feature is implemented in pure Common Lisp.

• WAV and Au format support
  • Reading and writing of files both all-at-once and as a stream of samples
  • Sample rates from 1hz to whatever your CPU/RAM can handle
  • Channels from 1 to whatever your CPU/RAM can handle
  • Integer and IEEE Floating Point sample support
  • Min/Max sample calculations and RMS calculations for input files
• Encoders/Decoders
  • MPEG-1 layers I, II, and III (e.g. mp3, via libmpg123)
  • FLAC (decoding only)
  • QOA codec
  • Extended QOA Format codec
  • WavPack (via libwavpack)
  • Vorbis (decoding only)
  • YM2610 ADPCM-A codec
  • High quality μ-law and A-law codec
• Processing
  • Bit-depth conversion with optional TPDF dithering
  • Integer -> Floating Point sample conversions
  • High quality resampler (a native port based on libsamplerate)
• Effects
  • Parametric EQ with low/high shelves and unlimited bands.
  • Soft clipping
  • Stereo enhancement
  • Zita-Rev1 reverb effect (native port)
  • MVerb reverb effect (native port)
  • Chorus effect inspired by an 80s synth with model number ending in “-60”
  • DC filter
  • Generic lowpass filter
  • CEM-style filter
  • Wasp-style filter
  • MS-20-style filter
  • SSM-style filter
• Other
  • Windowing functions (Blackman, Blackman-Harris, Hamming, Nuttall, Blackman-Nuttal, Hann)
  • CUE sheet reading and writing
  • XSPF and JSPF reading and writing
  • Raw Vorbis Comments reading and writing
  • Raw APEv1 and APEv2 tag reading and writing
  • ReplayGain calculation support.
  • MusicBrainz API support.
  • ListenBrainz API support.
• Output
  • Abstract “AUDIO-DRIVER” protocol to smooth-over the differences in various output backends
  • ALSA backend
  • libao backend
  • out123 backend
  • TCP backend - send audio over a TCP connection

Sub-Packages

The base package is cl-remiaudio is kind of like a “meta package' that loads all of the sub packages. The sub packages can also be loaded individually, and all have nicknames for shorter usage:

• cl-remiaudio-core (cl-ra): Base package containing various common routines.
• cl-remiaudio-codecs (cl-ra/codecs): Base package for all codecs.
• cl-remiaudio-codecs-mpeg1 (cl-ra/mpeg1): MPEG-1 decoder.
• cl-remiaudio-codecs-flac (cl-ra/flac): FLAC decoder.
• cl-remiaudio-codecs-qoa (cl-ra/qoa): QOA and Extended QOA Format encoders and decoders.
• cl-remiaudio-codecs-wavpack (cl-ra/wv): WavPack encoder and decoder.
• cl-remiaudio-dithering (cl-ra/dith): Dithering and sample format conversions.
• cl-remiaudio-dsp (cl-ra/dsp): Various effects/processors.
• cl-remiaudio-replaygain (cl-ra/rg): ReplayGain calculation support.
• cl-remiaudio-replaygain-parallel (cl-ra/rg-parallel): Additional parallel-processing support for ReplayGain calculations.
• cl-remiaudio-formats (cl-ra/formats): WAV and Au file I/O.
• cl-remiaudio-ogg (cl-ra/ogg): Ogg demuxer and Vorbis Comments parser.
• cl-remiaudio-cue (cl-ra/cue): CUE file reading and writing functions.
• cl-remiaudio-xspf (cl-ra/xspf): XSPF and JSPF file reading and writing functions.
• cl-remiaudio-ape (cl-ra/ape): Raw APEv1 and APEv2 reading and writing functions.
• cl-remiaudio-drivers (cl-ra/drivers): Base package for backend audio output drivers.
• cl-remiaudio-drivers-ao (cl-ra/driver-ao): Audio output via libao.
• cl-remiaudio-resampler (cl-ra/resamp): Fast, high quality resampler.
• cl-remiaudio-listenbrainz (cl-ra/lb): ListenBrainz and MusicBrainz API support.