[Mp4-tech] Re: Mpeg4 aac testing

[Ralph Sperschneider]

Mohan Reddy wrote:
> 
> Hi all,
> 
> Can anyone please let me know how to test the mpeg4 aac codec,
> 1> what should the o/p of encoder or decoder be tested with

No conformance test is specified for the encoder - the only criterion is that it 
generates valid compressed data. The easiest way to check whether the generated 
compressed data is valid is to fed it into the reference software decoder.
The conformance criteria for the decoder are specified in ISO/IEC14496-4.
> 2> Is an rms utility required for this and what is the maximum value of
> rms value for the codec to pass the test vector

Yes, an rms utility is required. The maximum value of the rms value is specified 
in ISO/IEC14496-4.
> 3> were do I get the rms utility, can any one send me the link to the same.

The rms utility (ssnrcd) can be found in the electronic attachment of 
ISO/IEC14496-5. The latest publicly available version can be retrieved here: 
http://standards.iso.org/ittf/PubliclyAvailableStandards/c043465_ISO_IEC_14496-5_2001_Amd_10_2007_Reference_Software.zip.
> 4> I have  a code which takes .adts inputs how do I make it to
> take .mp4 inputs. If any knows were to get the parser for .mp4 pls let 
> me know.

ISO/IEC14496-5 provides a converter (adif2mp4), which is able to convert between 
the AAC formats adif, adts and mp4.
> and also format of the .mp4 header also

The mp4 file format is specified in ISO/IEC14496-14.
Best regards,
Ralph
-- 
Dipl.-Ing. Ralph Sperschneider  | Phone: +49 9131 776 344
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