[Matroska-devel] Re: AAC and SBR

Moritz Bunkus moritz at bunkus.org
Thu Apr 27 09:54:42 CEST 2006


Hey,

On Wednesday 26 April 2006 09:52, Zen wrote:

> If I understand well, private data for AVI (and MP4) of a HE-AAC are
> different from other AAC (for me, the ADTS header is 8 byte long)

Most "proper" container formats (MP4, AVI, Matroska, RMFF) contain the
private data for AAC. This is usually 2 bytes long for normal AAC and 5
bytes for HE-AAC.

Raw AAC files with ADTS headers (or even worse, ADIF headers) do NOT
contain these 2 or 5 bytes at all. For such files only decoding the AAC
data actually gives you the information whether or not the file uses
HE-AAC. Neither AVI Mux GUI nor mkvmerge contains an AAC decoder and
never will.

Regards,
Mosu

-- 
If Darl McBride was in charge, he'd probably make marriage
unconstitutional too, since clearly it de-emphasizes the commercial
nature of normal human interaction, and probably is a major impediment
to the commercial growth of prostitution. - Linus Torvalds

-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 191 bytes
Desc: not available
URL: <http://lists.matroska.org/pipermail/matroska-devel/attachments/20060427/cda2a48d/attachment.pgp>


More information about the Matroska-devel mailing list