[FFmpeg-devel] [PATCH] avfilter/vf_guided: support enhanced guided filter

[Xuewei Meng]

I would like to explain the supported modes in the guided filter,
(1) Basic mode shows better denoising performance compared to bilateral
filter and can be applied in many applications such as detail enhancement,
dehazing, and so on, which is illustrated in paper
http://kaiminghe.com/eccv10/.
(2) Fast basic mode is the fast algorithm of basic mode by downsampling
method, which is recommended by http://kaiminghe.com/eccv10/. When the
downsampling ratio is too large, blocking artifacts may occur. We can
further improve this next step.
(3) Enhanced mode is based on the local edge information, which can better
preserve the detailed information. We propose this mode in the second
period of GSoC.
(4) Fast enhanced mode is the fast algorithm of enhanced mode by
downsampling method.

And the memory reallocation is indeed an issue of this filter, which can be
improved.

All in all, we believe that guided filter is an important tool and has been
proved to be very useful in many applications. So keep this filter is a
better choice.


Bests,
Xuewei

Paul B Mahol <onemda at gmail.com> 于2021年10月22日周五 下午3:28写道：

>
>
> On Wed, Oct 13, 2021 at 3:57 PM Paul B Mahol <onemda at gmail.com> wrote:
>
>> Why this filter is being applied at first place at all?
>>
>> It is extraordinary slow and used very slow algorithm and reallocates
>> memory all the time.
>>
>
> Additionally so called fast mode, which is indeed faster than bilateral
> filter, is unusable and have blocking artifacts.
>
>
> I vote for removal of this filter.
>