HydrogenAudio

Lossy Audio Compression => AAC => AAC - General => Topic started by: soman on 2007-12-21 09:37:21

Title: .m4a encoded packaging
Post by: soman on 2007-12-21 09:37:21
Hello
      I want to know the packaging of .m4a encoded data i.e. how samples of one frame and corresponding scalefactors information is package in .m4a file format.
Thanks
soman N
Title: .m4a encoded packaging
Post by: benski on 2007-12-21 17:37:26
The AAC data is stored normally, but there is no header.  Decoder configuration information is stored in a special place.  Each 'sample' in the mp4 file contains one frame of AAC.

The file format and AAC codec format are too complicated to explain in a forum post.  Information about the MP4 file format can be found in MPEG-4 Part 12 and 14.  Information about the AAC codec can be found in MPEG-4 Part 3.  These documents may be purchased from ISO.