[FFmpeg-devel] lavc/aarch64: add simple idct neon functions

[Matthieu Bouron]

On Wed, Mar 15, 2017 at 01:14:42PM +0100, Matthieu Bouron wrote:
> On Mon, Mar 06, 2017 at 03:48:57PM +0100, Matthieu Bouron wrote:
> > On Thu, Feb 23, 2017 at 04:59:16PM +0100, Matthieu Bouron wrote:
> > > Hello,
> > > 
> > > The following patchset add the ff_simple_idct function neon functions for the
> > > aarch64 platform. It's ported from armv7 simple_idct_neon with some improvements:
> > >  * the source idct blocks are now loaded once and kept in v24-v31
> > >  * the source idct blocks are no longer overriden in idct_col4_top
> > >  * the destination is now written in one pass at the end of
> > >    ff_simple_idct{,_put,_add}_neon
> > > 
> > > It is bitexact with the armv7 neon implementation.
> > > 
> > > Here are some results (reported by {START,STOP}_TIMER) on an Odroid-C2 (Cortex
> > > A53):
> > > 
> > > Functions             IDCT: simple       IDCT: simpleneon
> > > ff_simple_idct_put     9795 units        3170 units
> > > ff_simple_idct_add    10227 units        3302 units
> > > 
> > 
> > Ping.
> 
> I'd like to push the patch tomorrow if there is no objection.
> 
> If that helps, here is the output of mjpegdec with simple and simpleneon
> idct methods.
> 
> Original: http://0x5c.me/idct/original.jpg
> Simple: http://0x5c.me/idct/simplec.png
> Simpleneon: http://0x5c.me/idct/simpleneon.png
> 
> The diff between simple and simpleneon shows off some off by 1
> differences: http://0x5c.me/idct/diff.png (simpleneon aarch64 is bitexact
> with its armv7 counterpart though).

Patchset pushed.

Matthieu

[...]