[Mp4-tech] Re: Reference Waveforms

[Ralph Sperschneider]

Shailesh Sakri wrote:
>Hi,
>I have downloaded the reference waveforms for conformance testing of MPEG 4
>AAC Decoder.
>I found that the header information of these wav files are corrupted. I was
>unable to open these files in Cooledit and even Matlab.
>  
>
The header is not corrupted, but your Cooledit does not support the wav 
extensible format (try the Windows media player, it will play the wav 
files).
>I had also downloaed the mp4 files and decoded using fadd. I found that the
>file sizes of fadd decoded file and reference wav are differing.
>  
>
This might be due to frames skipped by the decoder at the beginning or 
the end, or due to different wav header sizes, or due to the fact that 
faad wrote samples with 16 bit accuracy, while the reference waveforms 
provide 24 bit per sample.
>Can anyone give me some pointers of why is this happening. If these are not
>the correct reference waveforms then where can i get these?
>  
>
An answer to the latter question would require that you disclose the 
site you have downloaded the data.
>                           SASKEN BUSINESS DISCLAIMER
>This message may contain confidential, proprietary or legally Privileged information. In case you are not the original intended Recipient of the message, you must not, directly or indirectly, use, Disclose, distribute, print, or copy any part of this message and you are requested to delete it and inform the sender. Any views expressed in this message are those of the individual sender unless otherwise stated. Nothing contained in this message shall be construed as an offer or acceptance of any offer by Sasken Communication Technologies Limited ("Sasken") unless sent with that express intent and with due authority of Sasken. Sasken has taken enough precautions to prevent the spread of viruses. However the company accepts no liability for any damage caused by any virus transmitted by this email
>  
>
Please do not use those disclaimers while sending e-mails to open 
reflectors (unless you don't expect an answer, since noone will be sure 
that she/he is the original intended recipient).
-- 
Dipl.-Ing. Ralph Sperschneider  | Phone: +49 9131 776 344
Fraunhofer IIS                  | Fax:   +49 9131 776 67 344
Am Wolfsmantel 33               | mailto:ralph.sperschneider iis.fraunhofer.de
D 91058 Erlangen                | http://www.iis.fraunhofer.de/amm/