[M4IF Technotes] Re: MPEG4 Confirmance BitStreams

[Ralph Sperschneider]

Dear Anil,
Anil Kumar wrote:
> Hi Ralph,
> 	Can you tell me where to find a detailed description of all the MPEG-4 bit streams?? (similar to w5373 (study on MPEG-2 AAC Conformance) of MPEG-2)??. As we (Ittiam) are ISO members, I have access to all the MPEG sites including the mpeg.nist.gov site where I found the w5373 doc. 
The most recent MPEG-4 conformance document is N5457.
> Also, where can I find the CRC polynomial or at least a source code that REALLY works??
I guess you are looking for the crc_check derivation in the adts header. It is 
originally specfied in ISO/IEC 11172-3 (MPEG-1 Audio), subclause 2.4.3.1 
(G(X)=X^16+X^15+X^2+1). The CRC derivation in the multichannel decoder 
(mp4audec_mc   mp4mcDec) of the MPEG-4 audio reference software works properly.
> 	I am not sure if I can ask you all these questions, but hoping for a reply this time around :-)
Hope this helps.
> 
> Best regards,
> Anil
> 

Best regards,
Ralph
-- 
Dipl.-Ing. Ralph Sperschneider  | Phone: +49 9131 776 344
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