I thought Image::Magick had a method to read a pixel color but, I could not find one. But GD does - The only problem, GD doesn't seem to handle TIF natively, so you may have to do a conversion to an uncompressed JPEG or PNG.

From the GD Docs: 

$index = $image->getPixel(x,y) object method

    This returns the color table index underneath the specified point.
+ It can be combined with rgb() to obtain the rgb color underneath the
+ pixel.

    Example:

            $index = $myImage->getPixel(20,100);
            ($r,$g,$b) = $myImage->rgb($index);

[download]


grep
One dead unjugged rabbit fish later

In reply to Re: Perl Image Analysis by grep
in thread Perl Image Analysis by Anonymous Monk

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