In  $img_gry->Set('pixel[$col,$row]' => 'rgb($sub_red, $sub_green, $sub_blue )'); the single quotes prevent interpolation which means Image::Magick is given the strings '$col', and '$row' instead of the values you expect. I didn't read the documentation to see if anything else is wrong, but this does look highly suspicious. Aren't you getting any warnings for that? I'm surprised Image::Magick doesn't complain about the invalid input.

In reply to Re: Pixel setting oddity - Image:Magick by Eily
in thread Pixel setting oddity - Image:Magick by merrymonk

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