The FAAC project includes the AAC encoder FAAC and decoder FAAD2. It supports several MPEG-4 object types (LC, Main, LTP, HE AAC, PS) and file formats (ADTS AAC, raw AAC, MP4), multichannel and gapless en/decoding as well as MP4 metadata tags. The codecs are compatible with standard-compliant audio applications using one or more of these profiles.
Xmcd is a full-featured CD player and ripper software suite including xmcd and cda. Both utilities transform your CD drive into a stereo CD player, allowing you to play music CDs on your computer, as well as perform digital audio extraction (DAE) into files or streams of various formats. Multi-disc CD changers are also supported on many platforms. Xmcd features CDDB disc recognition, web browser integration for content related to the playing CD, local discography management, full feature-specific help system, remote control capability, and more.
YaRET is a Perl script that automates the ripping, normalization, and encoding of CDs. It supports CDDB very well via the Perl Audio::CD module, and also can work with your favorite ripper/normalizer/encoder (e.g., cdparanoia, cdda2wav, normalize, etc.) It supports useful features like multiple concurrent encoders and an easy to use configuration file that lets you customize YaRET to your taste (such as file naming based on the CDDB information).
KAudioCreator is an audio file creation solution for KDE. Ripping the files using KDE (with CDDB support), it allows you to use whatever encoder you wish to encode your audio files. It also provides a job control system so you can see what files have succeeded or failed, and stop or cancel jobs as the application progresses.
mp3Rip is yet another MP3 ripper. This one requires very little user intervention--you just have to insert the CD and start the program. It rips the songs as quickly as possible so another CD can be started while other CDs are being compressed. It also organizes MP3s using CDDB information, and it can recover from errors with minimal wasted effort.
crip is a terminal-based ripper/encoder/tagger tool for creating Ogg Vorbis files (or MP3 files for crip 1.X) under Unix/Linux. It is well-suited for someone seeking to make a lot of Ogg/MP3 files from CDs and have them all properly labeled and professional-quality with a minimum of hassle.
Wagtail is a client/server-based tool for audio encoding. It is designed to make it easier to encode and organize files in bulk. Wagtail allows you to enforce standards across your media collection with the use of "formats", each describing an audio format, how to encode/tag, etc. It also uses "classes", a combintation of formats and quality settings, as well as "tasks", which set the naming conventions, file locations, and reprocessing stages for files, and restricts which classes can be used. It includes wagdisc for ripping CDs and wagfile for processing files.
Mp3tag is an Objective-Caml library for reading and writing ID3v1 and v2 tags in MP3 files. It includes mp3tag tools, which can be used to modify tags in MP3 files or rename files according to their tags, and a cddbtag tool that modifies tags by using a CDDB server to retrieve information about the track.
ripx is a script designed to make ripping CDs as easy as possible. It features CDDB lookup, ID3 tag editing prior to ripping, playlist file generation, album directory creation, and generally a nicer interface than many similar tools. By default, ripx uses cdparanoia to extract audio from CDs and lame to encode the audio to MP3 format at the quality of your choice. If you wish to use alternative applications for extraction or encoding, modifying ripx to handle these should be fairly painless.