[Mp4-tech] Re: [Audio] Information on how to create AAC LC with LATM header

Tue Oct 23 10:26:26 EDT 2007

Sharma, Sreejana wrote:
> Hello all,
> 
> I am working on creating AAC LC audio content with LATM header. Is there 
> any tool available that can help me create that content. Also are there 
> any decoder available that can help me parse the LATM headers.

The MPEG-4 reference software decoder 
(http://standards.iso.org/ittf/PubliclyAvailableStandards/c043465_ISO_IEC_14496-5_2001_Amd_10_2007_Reference_Software.zip) 
can decoder latm files. It supports the LOAS type AudioSyncStream().
> Also can 
> I have an  AAC LC content with just LATM header and can any decoder 
> decode it.

You can find a couple of AAC LD test sequences here in the mentioned format:
ftp://mpaudconf:[email protected]/mpeg4audio-conformance/compressedAss/add-opt/*.ass
> Or does AAC with LATM have to be in some sort of file format 
> such as 3gp or mp4 file format.

No, it is wrapped in LAOS. LAOS comes in three different flavors, but only the 
AudioSyncStream() is currently used.
Best regards,
Ralph
-- 
Dipl.-Ing. Ralph Sperschneider  | Phone: +49 9131 776 344
Fraunhofer IIS                  | Fax:   +49 9131 776 398
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