Am 15.01.22 um 09:27 schrieb Paul B Mahol:
> On Sat, Jan 15, 2022 at 9:25 AM Paul B Mahol <onemda@gmail.com> wrote:
> 
>>
>>
>> On Fri, Jan 14, 2022 at 5:22 PM Thilo Borgmann <thilo.borgmann@mail.de>
>> wrote:
>>
>>> Hi,
>>>
>>> Am 19.01.21 um 05:49 schrieb Lynne:
>>>> Jan 19, 2021, 01:07 by borbarak@fb.com:
>>>>
>>>>> Calculate Spatial Info (SI) and Temporal Info (TI) scores for a video,
>>> as defined
>>>>> in ITU-T P.910: Subjective video quality assessment methods for
>>> multimedia
>>>>> applications.
>>>>>
>>>>> Update: Fixed bracket style.
>>>>>
>>>>
>>>> Thanks, looks much neater now.
>>>>
>>>>
>>>>
>>>>> I'm already adding the data to the frame's metadata, is the suggestion
>>> to remove the file option altogether?
>>>>>
>>>>
>>>> Yes. We want to avoid filters having their own file in/out options
>>> rather
>>>> than using generic ones.
>>>
>>> Updated the patch to apply to git HEAD.
>>> Removed file output.
>>> Made printing summary to console optional.
>>>
>>>
>>>>> +
>>>>> +#include "libavutil/imgutils.h"
>>>>> +#include "libavutil/internal.h"
>>>>> +#include "libavutil/opt.h"
>>>>> +
>>>>> +#include "avfilter.h"
>>>>> +#include "formats.h"
>>>>> +#include "internal.h"
>>>>> +#include "video.h"
>>>>> +
>>>>> +static const int X_FILTER[9] = {
>>>>> +    1, 0, -1,
>>>>> +    2, 0, -2,
>>>>> +    1, 0, -1
>>>>> +};
>>>>> +
>>>>> +static const int Y_FILTER[9] = {
>>>>> +    1, 2, 1,
>>>>> +    0, 0, 0,
>>>>> +    -1, -2, -1
>>>>> +};
>>>>>
>>>>
>>>> We have optimized assembly to apply 3x3 matrices. Check out
>>>> libavfilter/x86/vf_convolution.asm:ff_filter_3x3_sse4
>>>>  vf_convolution already applies a sobel filter that way. Maybe
>>>> look into sharing some DSP code with it?
>>>
>>> I checked a bit since I also want a common sobel for vf_edgedetect / my
>>> patch for vf_blurriness.
>>>
>>> For sobel, there is no direct asm implementation. We have a generic
>>> filter_3x3 with sse4 optimization. To use sobel with that, you'd need to
>>> run two times filter_3x3 plus one pass for gradient calculation.
>>>
>>> As another difference, this filter (SITI) does on-the-fly conversion to
>>> full-range pixel values during its sobel. While vf_edgedetect /
>>> vf_bluriness use an abbreviation for the gradients during its sobel. Which
>>> makes them both distinct enough not to fit into a general filter_3x3 or
>>> filter_sobel from vf_convolution easily (and more overhead). So I think
>>> it's not worth the effort to force them into a common function? (Especially
>>> since we don't have a sobel_sse4 or something)
>>>
>>> Patch without a common sobel attached.
>>>
>>>
>>
>> Violations of code style.

Enhanced.


>> Also why filter description only shows SI part and TI part is missing?

Mentioned.

v2 attached.

Thanks,
Thilo