Monks,

I am working on a project to extract wave height data from about ten years of hourly images. Across the image, I can calculate the the pixel (x and y) of the site I want to extract data from. The pixel at that site has a color that corresponds to a standard wave height value.

My question is, how do I extract that pixel color? I've seen lots of code flying around for filling colors with a certain pixel color, but not so much on extracting information from a pre-existing image.

Any pointers? Would something in GD or other module work?

In reply to Extracting pixel values by redbeard

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