AAC bitstream format?

[unixfs]

Hi,
I need a short description of AAC[24] bitstream format,
not the whole spec(although that would be useful too)
but only an explanation of the values used for syncword,
headers(bitrate/profile/level), etc.

I need it because in some cases it's embedded in TS streams
with the same syntax as MPA, and obviously I have to pass each of
the streams to different decoders.

Any help is very appreciated.

Thanks very much.

[DSPguru]

w2203tfs.pdf (http://www.tnt.uni-hannover.de/project/mpeg/audio/documents/)

[unixfs]

Great, thanks!

[Nic]

Using the PMT and PAT you should be able to determine the type of stream without parsing the actual ES stream ? Is that not the case ?

-Nic

[unixfs]

Not always:
there are standard formats to describe AAC in the PMT (0x11 as ES_type
in the ES loop), but certain japanese broadcasters don't follow the rules, and even add AAC in MPA PES format to the multiplex.
This is a real mess.

[Nic]

Broadcasters not following standards is always a nightmare. Thanks for the info :)

-Nic

[alexnoe]

Is it just me, or is ac3 and dts muxing simple compared to aac?

[unixfs]

Ac3 in TS can appear in n+1 different forms, managing it is not a joke.


"Infinite differences in infinite combinations"