[FFmpeg-devel] [PATCH v6 2/4] avfilter/vf_framerate: if metadata lavfi.scd.mafd exists, we'll use it first

[Marton Balint]

On Thu, 14 May 2020, Nicolas George wrote:

> Marton Balint (12020-05-14):
>> I am not a huge fan of this patch, mafd refers to a score between this frame
>> and the previous frame, we cannot ensure that there were no additional frame
>> processing between scdet and this filter which may have duplicated or
>> removed frames. So I'd rather not add this feature.
>
> It can only happen if the user has put filters in the middle. I move we
> trust users who insert such obscure filters to do what they want to, or
> to fix their issues if they have some.

Fine, I am not blocking this if null pointer deref issues are fixed.

I think we can also assume that if the metadata exists, it will contain a 
valid number, so I suggest this code:

         e_mafd = av_dict_get(next->metadata, "lavfi.scd.mafd", NULL, AV_DICT_MATCH_CASE);
         if (e_mafd) {
             mafd = strtod(e_mafd->value, NULL);
         } else {
             s->sad(crnt->data[0], crnt->linesize[0], next->data[0], next->linesize[0], crnt->width, crnt->height, &sad);
             emms_c();
             mafd = (double)sad * 100.0 / (crnt->width * crnt->height) / (1 << s->bitdepth);
         }

Regards,
Marton