[Ffmpeg-devel] MPEG4 over TS

Nico Sabbi nsabbi
Fri Jun 3 10:58:35 CEST 2005

Erik Slagter wrote:

>On Thu, 2005-06-02 at 17:40 +0200, Nico Sabbi wrote:
>>this is for AAC in LATM syntax, but since vlc always/mostly uses ADTS 
>>syntax the correct stream_type is 0x0f.
>>BTW, don't top-post, please
>I am trying to get a bit of a grip on all mpeg terminology. Am I right
>that ADTS is the trick to put ac3 sound into a mpeg2 program stream
>using private_1 stream and then prepending the data with a single byte
>specifying the actual data?
no, you are wrong :) 
AC3 is stored in dvd's implementation of mpegps using a technique called 
the first bytes of the payload indicates a substream_id, the other N-1 
bytes (for ac3 N=4) indicate
how many frames begin in the current pes and where the first byte of the 
first frame
starts (in byte offsets) after the 4 bytes. For LPCM N is 6 or 7 (not 
sure). For DTS I don't know.
Overall it's a kind of silly muxing inside the mux that I don't like.

>And what would LATM then be (in three words ;-))?

another syntax for AAC. These aac people seem to get never tired of 
pulling out new dialects

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