The Imager module has the ->getpixel() method which can read the colour value at a location in an image. I guess that all the other imaging modules (Image::Magick, GD,...) also have comparable routines, but I don't know them.

In reply to Re: Script or Module to recreate underlying data from a graph/chart image by Corion
in thread Script or Module to recreate underlying data from a graph/chart image by whakka

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