[Mp4-tech] Re: AACPlus test streams

[Ralph Sperschneider]

Anil Kumar wrote:
> Dear Ralph,
> 	Can you please tell me as to when the HE-AAC test streams will be ready? Also, what is the criteria for testing HE-AAC(is it the same as AAC with rms/max difference for sine-sweeps?)
> 
> Thanks,
> Anil
> 

Dear Anil,
AACPlus is a marketing name, its not used in the MPEG world.
HE-AAC labels a profile ("High Efficiency AAC Profile"). That profile contains 
the object types 2 (AAC LC) and 5 (SBR).
In MPEG-4 Audio, the conformance test is individually specified for 
AudioObjectTypes. Hence, if you want to lable your decoder as conform to the 
Hight Efficiency AAC Profile you have to test it on AAC LC _and_ SBR conformance.
The conformance criteria and test sequences for AAC LC are already well defined 
and available.
For SBR, the specification on conformance has just started (it is still just a 
working draft, the document number is N5724). No sequences are available yet.
Best regards,
Ralph
-- 
Dipl.-Ing. Ralph Sperschneider  | Phone: +49 9131 776 344
FhG IIS                         | Fax:   +49 9131 776 398
Am Wolfsmantel 33               | mailto:sps iis.fhg.de
D 91058 Erlangen                | http://www.iis.fhg.de/amm/