[FFmpeg-devel] rectification filter

[Daniel Oberhoff]

Am 30.07.2014 um 00:08 schrieb wm4 <nfxjfg at googlemail.com>:

> On Tue, 29 Jul 2014 00:31:48 +0200
> Daniel Oberhoff <danieloberhoff at gmail.com> wrote:
> 
>> Hello,
>> 
>> In the last days I effectively rewrote the rectification filter found in the frei0r suite as a libavfilter video filter and would like to submit this to ffmpeg. It probably needs some cleanup, which I will do by checking your commit guidelines, but I would like to get a first opinion also if this would actually be accepted.
> 
> Can I ask why vf_frei0r is not sufficient? As I understand, it provides
> a way to use frei0r filters in libavfilter. Just curious.

Frei0r requires afaik rgb non-planar formats, which are not native to ffmpeg, and thus a lot of conversion effort, which slows things down considerably (not measured, but 2x should be a lower bound). and even worse frei0r does not allow slice parallelization, and thereby limits the throughput in a way that is unacceptable for my use-case (I need to push around 4MP at 20fps, while doing decoding/encoding into several streams).

Maybe frei0r could be “fixed” there, but I found it simpler to do it this way. Also by getting it upstream it would ease deployment by just pulling ffmpeg master, and maybe sometime even land in linux distros off-the-shelve, which is quite appealing.

Best

Daniel