Pixel by pixel operation on image in Google App Engine using Python

I would like to go over an image and do some pixel by pixel operation. The image API provided by Google App Engine seems to be incapable to do this开发者_如何学JAVA. And it doesn't include Python Imaging Library. So, how should I proceed with it.

Thanks..

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You could maybe use the image API to convert to PNG, then use the png module (which is pure python, so should hopefully run on app engine) to load the PNG and modify the pixels. Then convert back to PNG using the png module, and back to whatever format you need using the image API.