[FFmpeg-devel] [FFmpeg-cvslog] ac3enc: use generic fixed-point mdct

Michael Niedermayer michaelni at gmx.at
Mon Apr 4 03:20:00 CEST 2011


On Mon, Apr 04, 2011 at 03:01:16AM +0200, Mans Rullgard wrote:
> ffmpeg | branch: master | Mans Rullgard <mans at mansr.com> | Mon Mar 21 18:07:59 2011 +0000| [79997def65fd2313b48a5f3c3a884c6149ae9b5d] | committer: Mans Rullgard
> 
> ac3enc: use generic fixed-point mdct
> 
> This makes the AC3 encoder use the shared fixed-point MDCT rather
> than its own implementation.  The checksum changes are due to
> different rounding in the MDCT.
> 
> Signed-off-by: Mans Rullgard <mans at mansr.com>

I havnt checked if you are still subscribed but this change causes
the ac3 encoder to flip the sign of all samples. It also results
in encoder->decoder to have fliped output.

I thus conclude this code has not been tested at all as any quality
test would have revealed this

[...]
-- 
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