[FFmpeg-devel] [PATCH 4/4] avfilter/vf_colormatrix: add 10 & 12 bit depth support

[Thomas Mundt]

Ronald S. Bultje <rsbultje at gmail.com> schrieb am So, 27.3.2016:
> On Sun, Mar 27, 2016 at 7:09 AM, Thomas Mundt <loudmax-at-yahoo.de at ffmpeg.org> wrote:
>
>> >>>Ronald S. Bultje <rsbultje at gmail.com> schrieb am Sa, 26.3.2016:
>> > On Sat, Mar 26, 2016 at 10:04 AM, Thomas Mundt <loudmax-at-yahoo.de at
>> ffmpeg.org> wrote:
>> >
>> >>>>>Kieran Kunhya <kierank at obe.tv> schrieb am Sa, 26.3.2016:
>> >> >> On Fri, 25 Mar 2016 at 22:32 Thomas Mundt <loudmax-at-yahoo.de at>
>> ffmpeg.org> wrote:
>> >> >
>> >> >> Signed-off-by: Thomas Mundt <loudmax at yahoo.de>
>> >> >> ---
>> >> >>  libavfilter/vf_colormatrix.c | 182
>> >> >> ++++++++++++++++++++++++++++++++++++++++++-
>> >> >>
>> >>> >
>> >> > These functions are basically the same, have you considered factoring
>> the
>> >> > code out?
>> >> >
>> >> > Kieran
>> >>
>> >> I thought keeping it seperate would be easier to review.
>> >> But I can do that. Maybe as a subsequent patch?
>> >
>> >
>> > I think he means templating out typelessly like h264/hevc/vp9 do. I agree
>> > that would probably be nicer. Binary size is same but less duplicated
>> code.
>> >
>> > Ronald
>>
>> Okay, I tried to solve this with the use of macros. The attached file is
>> the result (interesting part starting at line 203).
>> It works, but I´m not sure if this is what you expect.
>> Also I didn´t find a way factoring out the two different av_clip.
>> One could replace av_clip_uint8 by av_clip with limits 0 and 255. But this
>> would have an impact on speed.
>> If there is a more elegant way, could you please provide a short example?!
>
>
> We don't like macros, but you're surprisingly close. Have a look at
> libavcodec/bit_depth_template.c and grep for its usage in libavcodec.
> 
> You'll end up with a vf_colormatrixdsp_template.c file, which includes
> bit_depth_template.c for types/clips etc., and it will then define full
> functions per bit depth. This is included in vf_colormatrixdsp.c, and that
> defines the actual dsp functions which do the core of what this filter does.
> 
> Since it's now in a dsp file, it'll be trivial to write x86 simd for it
> (which I have also in the works).
> 
> Ronald

I looked into this and sadly have to say that this would take much more time than I have atm.
I´m not a professional programmer so I would have to fiddle out the most things.
Sorry, but then I think it´s maybe better to drop the high bit depht support patch for now.

Thomas