[FFmpeg-devel] Default dynamic range compression on AC3

Michael Niedermayer michaelni at gmx.at
Thu Mar 26 12:40:45 CET 2015


On Thu, Mar 26, 2015 at 09:44:06AM +0100, Wiebe Cazemier wrote:
> ----- Original Message -----
> > From: "madshi" <madshi at gmail.com>
> > To: "FFmpeg development discussions and patches" <ffmpeg-devel at ffmpeg.org>
> > Sent: Thursday, 26 March, 2015 8:49:28 AM
> > Subject: Re: [FFmpeg-devel] Default dynamic range compression on AC3
> > 
> > Doesn't really matter. What does matter is a reasonable default choice. And
> > it's currently wrong, IMHO. Screw the AC3 spec which wants it to be on by
> > default. That's just stupid. Just my 2 cents, of course.
> 
> Is it even in the spec? If so, Dolby seriously shot themselves in the foot. No wonder DTS won the audio war on DVD.
> 
> I remember about 10 years ago that I found this setting in WinDVD. After switching to Linux and Xine, I discovered that AC3 can actually sound very good. Guess what: I found out that even with WinDVD set to full range, DRC was still applied!
> 
> This wrong default and the fact that a lot of people (developers, audio philes, etc) don't know about the DRC metadata has been following me for years. 
> 
> So who can decide this (or whom can I persuade :))? I can write a patch, shouldn't be too hard :). 

can you provide a sample (short/small one preferred) that "shows" that
a real world sample sounds better with a changed default ?

not critical but does someone have a list of titles which sound better
with one or the other default ?

and yes, please post a patch, this also should bump the version number
and add a note in the Changelog file



> 
> And then I have to also take it up with Libav? I'm confused about libavcodec in ffmpeg and libav.
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> 

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

You can kill me, but you cannot change the truth.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 181 bytes
Desc: Digital signature
URL: <https://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20150326/b250ac3e/attachment.asc>


More information about the ffmpeg-devel mailing list