Editing an UIImage

Posted by wwrob on Stack Overflow See other posts from Stack Overflow or by wwrob
Published on 2010-05-13T18:30:13Z Indexed on 2010/05/13 18:34 UTC
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objective-c

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cocoa

I have an UIImage that I want to edit (say, make every second row of pixels black). Now I am aware of the functions that extract PNG or JPEG data from the image, but that's raw data and I have no idea how the png/jpeg files work. Is there a way I can extract the colour data from each pixel into an array? And then make a new UIImage using the data from the array?

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