:: Re: [Frei0r] FFmpeg & bgsubtract0r
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Autore: salsaman
Data:  
To: Minimalistic plugin API for video effects
Oggetto: Re: [Frei0r] FFmpeg & bgsubtract0r
Hi Kernc,
I just tested this out in LiVES (http://lives-video.com) and I'm guessing
the issue might be that the filter only seems to alter the alpha component
of the frames. So probably what you would need to do is overlay the result
on top of some neutral background using an alpha blend.

HTH,
Salsaman.







On Sat, 20 Jun 2020 at 10:14, Kernc <kerncece@???> wrote:

> Hi,
>
> I'm trying out a ffmpeg pipeline for anonymizing webcam video. One of
> the filters I'd like to include is bgsubtract0r, but command line such
> as the following has no perceivable effect:
>
>     ffmpeg -i /dev/video0 -ss 1 \
>         -vf "frei0r=bgsubtract0r:0.5" \
>         -pix_fmt yuv420p -f xv - | ffplay -

>
> I guess I'm expecting a solid blue background as the filter's
> description states. I'm skipping the first second for the light and
> aperture to turn on and open, but even increasing `threshold`
> parameter all the way to 1 has no effect, so I doubt that's it.
> However, other frei0r filters seem to work great!
>
>     ffmpeg -i /dev/video0 \
>         -vf "frei0r=rgbsplit0r:0.1|0.1" \
>         -pix_fmt yuv420p -f xv - | ffplay -

>
> This is ffmpeg 4.1.4 and frei0r-plugins 1.7.0.
>
> I might be just using the filter wrong. Thanks for any clues!
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