Search found 3 matches

by skunkuncle
2016-03-21T00:12:21-07:00
Forum: Users
Topic: Extracting pixels within a certain hue bracket
Replies: 6
Views: 2530

Re: Extracting pixels within a certain hue bracket

Hi snibgo, hi fmw42 - thanks a lot!

I'd never used the "\(...\)" syntax - now I get it. Nice learning for me.

And yes, writing to JPG sucks, I shouldn't have! I'll fix it in the next version - today.

Thanks again to all.
by skunkuncle
2016-03-20T16:16:22-07:00
Forum: Users
Topic: Extracting pixels within a certain hue bracket
Replies: 6
Views: 2530

Re: Extracting pixels within a certain hue bracket

Thanks - following your hints and a bit of googling I ended up using the -fx option like this (unix syntax): convert "$1" -fuzz 15% -fill white -draw "color 0,0 floodfill" whited.jpg convert whited.jpg -fx "(hue > 0.17 && hue < 0.28) && lightness < 0.9 ? black : white" \ -morphology Erode Octagon ...
by skunkuncle
2016-03-20T01:50:34-07:00
Forum: Users
Topic: Extracting pixels within a certain hue bracket
Replies: 6
Views: 2530

Extracting pixels within a certain hue bracket

I would like to extract only pixels within a certain hue bracket - let's say within 15% of pure yellow - from an image. My purpose is to separate post-its of different colors from a picture of a whiteboard. Ideally it's shown here: http://imgur.com/a/nXmkq Where this http://imgur.com/0HDxdpj is the ...