The new version of this freeware player uses the Winamp input plugin from Audiocoding.com to decode AAC/MP4.

Reading list for an MIT seminar, most of the mentioned publications are directly available on their web server or linked to Amazon's book section.

Apple offers technical FAQs, knowledge base and publicly available documentation files including the MOV file format.

Commercial converter using FAAC and FAAD2 for AAC/MP4 support.

DirectShow filter suite from Dicas to decode MP4 and 3GP files or RTP streams of MPEG-4 content, also available as a standalone player application.

Windows tool identifying codecs in container formats like AVI, MPEG and MP4.

Besides this forum for audio codecs there are others for container formats and video encoding in general with FAQs.

The PHP media file parser extracts play time, bitrate and resolution from AAC and reads/writes ID3v1/v2 tags, supports other formats as well.

The GTK 2 port of XMMS with modern GUI features decodes AAC/MP4 with a patched plugin from the Lamip developer.

Relies on the external Winamp input plugin based on FAAD2 for AAC/MP4 support.

Movie soundtrack ripper which can extract any audio soundtrack from a DVD and rip the DVD audio to MP3, WAV, AAC, OGG, and WMA formats.

Plays and encodes AAC/MP4 with internal plugins since version 5.0, also decodes aacPlus Shoutcast streams and other formats.

Open source receiver and transmitter for Digital Radio Mondiale (DRM) using analog AM bands with HE AAC compressed sound at very low bitrates.

Comprehensive guides about DivX, XviD and MPEG4IP, a forum and other resources about digital audio/video coding and streaming.

Many TTS demos in several languages from different systems with links to their homepages.