On Tue, Sep 21, 2021 at 8:31 AM Michael Koch <astroelectro...@t-online.de> wrote:
> Am 20.09.2021 um 21:51 schrieb Paul B Mahol: > > On Sat, Oct 17, 2015 at 3:58 PM Michael Koch < > astroelectro...@t-online.de> > > wrote: > > > >> > That looks like the job for the filter, see inflate, deflate, > erosion > >> and dilation filters. > >> > >> I just tested the dilation filter. It's a nice workaround if the > >> downscaling factor is 3:1, as in my example. But if the downscaling > >> factor is smaller, for example from 5472x3648 to 900x600, which is 6:1, > >> then it fails. The star would be visible in 50% of the frames and > >> invisible in the other 50%. What I need is a scaling algorithm which > >> automatically chooses the brightest pixel out of the corresponding > >> pixels from the input file. If the downscaling factor is 6:1, then the > >> neighborhood is 6x6 pixels. > >> > > See new morpho filter, that gonna be in master soon. > > > > It is much faster than current filters and allow custom definition of > > structure/mask (rectangle/circle/etc) by using 2nd stream. > > That sounds interesting. > Is the size of the neighborhood over which the filter is working defined > by the size of the 2nd stream? > No, but by structure of pixels which are not 0 in value and are stored in 2nd stream. So you can use rectangle 6x6 with color=color=white:size=6x6 filter or edit structure in gimp. > Which pixel format must be used for the 2nd stream? > Anything. What's the meaning of the pixel values in the 2nd stream? White = pixel > is used, black = pixel is not used? What happens if a pixel is gray? > Is the original pixel in the center of the structure or is it the top > left pixel? > What's the meaning of "open" and "close"? > Please add some examples for the structure in the 2nd stream. > > Use google. and learn something about morphological transforms. FFmpeg can not also educate an uneducated. > Michael > > _______________________________________________ > ffmpeg-user mailing list > ffmpeg-user@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-user > > To unsubscribe, visit link above, or email > ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe". > _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".