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Find pixels by color

Apr 7, 2012, 15:02
Post: #1
Find pixels by color
Hi,

How can I find all pixels in an image with an exact, specific color? So far, I've only managed to find the pixels matching a pixel I click on; but I wish to find pixels matching a specific color value!

Thanks in advance Smile
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Apr 7, 2012, 16:55
Post: #2
RE: Find pixels by color
Quick way: Enlarge the layer by one pixel , paint an extra pixel with the required color, and click on it.

Math way:
- In the Channels, duplicate the Red channel (right click)
- Select the duplicated channel (should be highlighted in blue)
- start the Curves tool.
- drag the top-right end of the diagonal to the bottol
- select "Freehand" mode
- move your cursor along the top (Y=255) and click where X is the Red value you want
- this channel is now a mask where all the pixels with the required value of R are at 255 and the rest is at 0.
- repeat the above for the other two channels
- right click on the Red duplicate: channel to selection
- right click on the Green and the Blue: intersect with selection

Now answering your questions on
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