Turning an NSImage* into a CGImageRef?

objective-c cocoa core-graphics nsimage cgimage
Brian Postow picture Brian Postow · Mar 30, 2010 · Viewed 30.1k times · Source

Is there an easy way to do this that works in 10.5?

In 10.6 I can use nsImage CGImageForProposedRect: NULL context: NULL hints: NULL

If I'm not using 1b black and white images (Like Group 4 TIFF), I can use bitmaps, but cgbitmaps seem to not like that setup... Is there a general way of doing this?

I need to do this because I have an IKImageView that seems to only want to add CGImages, but all I've got are NSImages. Currently, I'm using a private setImage:(NSImage*) method that I'd REALLY REALLY rather not be using...

Answer

pheelicks picture pheelicks · Mar 30, 2010

Found the following solution on this page:

NSImage* someImage;
// create the image somehow, load from file, draw into it...
CGImageSourceRef source;

source = CGImageSourceCreateWithData((CFDataRef)[someImage TIFFRepresentation], NULL);
CGImageRef maskRef =  CGImageSourceCreateImageAtIndex(source, 0, NULL);

All the methods seem to be 10.4+ so you should be fine.

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