[FFmpeg-devel] [PATCH] mpegaudiodec: share identical tables between float and fixed decoder.

Michael Niedermayer michaelni at gmx.at
Mon Sep 1 11:50:18 CEST 2014


On Mon, Sep 01, 2014 at 09:30:04AM +0200, Reimar Döffinger wrote:
> On 01.09.2014, at 02:01, Michael Niedermayer <michaelni at gmx.at> wrote:
> > On Sun, Aug 31, 2014 at 10:47:09PM +0200, Reimar Döffinger wrote:
> >> ff_mpa_table_4_3_value alone saves over 128kB.
> > 
> > i wonder if that table shouldnt be something different in the float
> > implementation.
> > Also i think anyone caring about file size would likely not build
> > the float and fixed point mp3 decoder
> 
> There are other issues, having them twice IMHO makes a mess and it is unclear which tables actually differ between the documentation.
> Which in turn makes it very difficult to add support for hardcoding them (which is what I started out wanting to do).
> I also think some of these might only be used in one version of the decoder.

what i was thinking is that the decoders should be reviewed first to
make sure each uses the optimal data types and layouts, that is
possibly float based tables in the float decoder an int tables in the
fixed one. But also possibly more differences where it makes sense
(comparing to other open source mp3 decoders could also make sense)

and after the layout and types of the tables are optimal they would
be split into shared and non shared and hardcoded support be added

if they are shared now, it would require to undo that for tables
that end up only being used on one side later. So it seems this order
of doing things would end up being more work overall, but then some
of that is already done so dunno ...

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

In fact, the RIAA has been known to suggest that students drop out
of college or go to community college in order to be able to afford
settlements. -- The RIAA
-------------- 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/20140901/31db12c3/attachment.asc>


More information about the ffmpeg-devel mailing list