Need AC3 Specifications!

[smoof]

Can someone post a link to the specification for the header of an .AC3 file. I already have the ATSC A52 spec but that only specifies the AC3 bitstream. I looking for the specification of the header that precedes the first sync frame. I've search the forum and the net but haven't found it yet.


Thanks

[DSPguru]

a52, page 32, 5.3.1 - syncinfo - synchronization information.

[smoof]

Maybe I'm confused, but when I look at an .ac3 file using a hex editor, the first two bytes are not the syncword 0x0b77. The first sync word does not appear until several hundred bytes later. So what I'm looking for is something that describes what this first several hundred bytes contains.

This is for .ac3 files demuxed using Smart Ripper or DVD2AVI.

Thanks

[DSPguru]

the "problem" is with your file. not with the specs.

[DJ_Cyberdance]

Hi!
Has anyone an idea of how Dolby AC-3 encoding really works? I need some basic information about how the algorithms work. (Especially what is the difference between other lossy compressing algorithms like MP3, OggVorbis or others)
Thanks in advance!

[DSPguru]

http://forum.doom9.org/showthread.php?s=&threadid=41024&perpage=4&pagenumber=2

[Alphaloop]

Does anyone have information/documentation/material about the file format respectively the frame format of the AC3-files? (frame headers, construction of the file, ...)

If not, where can I get those infos?

[alexnoe]

http://www-user.tu-chemnitz.de/~noe/AC3.zip