[FFmpeg-devel] [PATCH 0/7] ARM NEON optimisations

[Måns Rullgård]

Panagiotis Issaris wrote:
> On Tue, 2008-12-16 at 10:57 +0000, M?ns Rullg?rd wrote:
>> Panagiotis Issaris wrote:
>> > Hi M?ns,
>> >
>> > On Fri, 2008-12-05 at 23:34 +0000, Mans Rullgard wrote:
>> >> The following patches add NEON optimised versions of various dsputil
>> >> functions.  I have improved some of the functions slightly since last
>> >> time I sent these patches.  I am not including a few patches which can
>> >> be improved further this time.
>> > ...
>> >> If I get no useful feedback, I will start applying these soon.
>>
>> I have committed these 7 patches.  More to follow.
>>
>> > I benchmarked video decoding with and without the NEON, and the frame
>> > rate nearly doubled! Great work!
>>
>> What hardware are you using?  Beagle board?  What samples did you try?
>
> Beagle board revision B6, which I received a few weeks ago.
>
> I mostly use movie trailers from the Quicktime/Apple website.
>
> I've tried various resolutions and samples, but here's a small extract
> of the output. Note that I had to fiddle a bit with the flags to get the
> NEON compiled in... and in searching how to get it to work, I stumbled
> upon the IRC log with the discussion regarding the broken CodeSourcery
> compiler. I've compiled these using CS's 2007q3 compiler.

Do you feel something could be done better in the FFmpeg configure
script?

> root at beagleboard:/# ./ffmpeg2007 -benchmark -i iceage3-tlrd_h320.mov -f
> null -an /dev/null
> FFmpeg version git-932edfb, Copyright (c) 2000-2008 Fabrice Bellard, et
> al.
>   configuration: --cross-prefix=arm-none-linux-gnueabi- --arch=armv7l
> --cpu=cortex-a8 --enable-neon --disable-devices --disable-network

It is preferred to use --arch=arm.  Variants are determined based on
--cpu and tests.  There is also no need to explicitly --enable-neon.
It will be enabled if the compiler supports it.

-- 
M?ns Rullg?rd
mans at mansr.com