If you have the RGB-values you can easily convert them to grayscale through the formula on Wikipedia where Y (luminance) is the grayscale intensity:

Y = 0.299 * R + 0.587 * G + 0.114 * B

Here is the link:
http://en.wikipedia.org/wiki/YUV

Anders, Norway

In reply to Re^4: Perl Image Analysis by rustyjuggler
in thread Perl Image Analysis by Anonymous Monk

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