xACT ~ Mac / WIndows Audio GUI


A Mac OSX GUI frontend for open source audio codecs. There is an older Windows version available as well.

xact_main

http://xact.scottcbrown.org

TooLAME ~ MP2 Audio Encoder


TooLAME is a free software MPEG-1 Layer II (MP2) audio encoder written primarily by Mike Cheng. While there are many MP2 encoders, TooLAME is well-known and widely used for its particularly high audio quality. It has been unmaintained since 2003, but is directly succeeded by the TwoLAME code fork (the latest version, TwoLAME 0.3.13, was released January 21, 2011). The name TooLAME is a play on LAME and Layer II.

http://sourceforge.net/projects/toolame/
http://www.twolame.org
http://en.wikipedia.org/wiki/TooLAME

FAAC ~ Freeware AAC Codec


FAAC is an Advanced Audio Coder (MPEG2-AAC, MPEG4-AAC). The goal of FAAC is to explore the possibilities of AAC and exceed the quality of the currently best MP3 encoders.

Features:

  • AAC-LC
  • High quality audio
  • High-speed encoding

http://faac.sourceforge.net
https://sourceforge.net/projects/faac
https://en.wikipedia.org/wiki/FAAC

WavPack ~ Hybrid Lossless Audio Compression


WavPack is a completely open audio compression format providing lossless, high-quality lossy, and a unique hybrid compression mode. For version 5.0.0, several new file formats and lossless DSD audio compression were added, making WavPack a universal audio archiving solution.

In the default lossless mode WavPack acts just like a WinZip compressor for audio files. However, unlike MP3 or WMA encoding which can affect the sound quality, not a single bit of the original information is lost, so there’s no chance of degradation. This makes lossless mode ideal for archiving audio material or any other situation where quality is paramount. The compression ratio depends on the source material, but generally is between 30% and 70%.

The hybrid mode provides all the advantages of lossless compression with an additional bonus. Instead of creating a single file, this mode creates both a relatively small, high-quality lossy file that can be used all by itself, and a “correction” file that (when combined with the lossy file) provides full lossless restoration. For some users this means never having to choose between lossless and lossy compression!

WavPack employs only well known, public domain techniques (i.e., linear prediction with LMS adaptation, Elias and Golomb codes) in its implementation. Methods and algorithms that have ever been patented (e.g., arithmetic coding, LZW compression) are specifically avoided. This ensures that WavPack encoders and decoders will remain open and royalty-free.

http://www.wavpack.com/
https://en.wikipedia.org/wiki/WavPack

Opus ~ Interactive Audio Codec


Opus is a lossy audio coding format developed by the Xiph.Org Foundation and standardized by the Internet Engineering Task Force, designed to efficiently code speech and general audio in a single format, while remaining low-latency enough for real-time interactive communication and low-complexity enough for low-end embedded processors. Opus replaces both Vorbis and Speex for new applications, and several blind listening tests have ranked it higher-quality than any other standard audio format at any given bitrate until transparency is reached, including MP3, AAC and HE-AAC. ~ Wikipedia

http://opus-codec.org
http://opus-codec.org/downloads/
Wikipedia