How can I auto-crop a pre-defined polygon shape from an image file?

Ideally using a Python library or processing.org, I need to import开发者_JAVA百科 an image and then crop a predefined polygon area from this image using x,y coordinates (vertices).

Thanks.

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Try PythonMagick. Your question appears to be a cut-and-dry application of crop through specification of image geometry.

(More ImageMagick ports and documentation.)

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Also check out PIL.

Though this is hardly library specific and almost every library should support this.