[Mp4-tech] Re: [HE-AAC] AAC+SBR conformance test

[Ralph Sperschneider]

Andy Quan wrote:
> hi,
> I got a question about the applicability of AAC+ conformance
> test(ISO/IEC 14496-4, Amendment 8). My decoder under test is a fixed
> point one with 16bit signed PCM output. Is this type of PCM applicable
> to procedures described in that test spec? 

To my understanding, it is.
> As ISO provides 24bit PCM
> as reference and I am worrying about this 8bit accuracy gap. Anyone
> got comment?
>
>   

Within the MPEG conformance suite, the decoded waveforms being 
counterparts of compressed data containing SBR are provided on an 
informal basis only, they are not required for the actual conformance 
test (but should rather give you an idea on how the output should 
look/sound). The SBR conformance tool just requires as input the 
compressed data (mp4 file) and the waveform of the decoder under test.
Best regards,
Ralph
-- 
Dipl.-Ing. Ralph Sperschneider  | Phone: +49 9131 776 6167
Fraunhofer IIS                  | Fax:   +49 9131 776 6099
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