Skip to content

Instantly share code, notes, and snippets.

@mazz mazz/gist:4259594
Created Dec 11, 2012

What would you like to do?
uses CGImageCreateWithImageInRect to perform a crop
// this chunk of code loads a jpeg image into a cgimage
// creates a second crop of the original image with CGImageCreateWithImageInRect
// writes the new cropped image to the desktop
// ensure that the xy origin of the CGRectMake call is smaller than the width or height of the original image
NSURL *originalImage = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"lockwood" ofType:@"jpg"]];
CGImageRef imageRef = NULL;
CGImageSourceRef loadRef = CGImageSourceCreateWithURL((CFURLRef)originalImage, NULL);
if (loadRef != NULL)
imageRef = CGImageSourceCreateImageAtIndex(loadRef, 0, NULL);
CFRelease(loadRef); // Release CGImageSource reference
CGImageRef croppedImage = CGImageCreateWithImageInRect(imageRef, CGRectMake(200., 200., 100., 100.));
CFURLRef saveUrl = (CFURLRef)[NSURL fileURLWithPath:[@"~/Desktop/lockwood-crop.jpg" stringByExpandingTildeInPath]];
CGImageDestinationRef destination = CGImageDestinationCreateWithURL(saveUrl, kUTTypeJPEG, 1, NULL);
CGImageDestinationAddImage(destination, croppedImage, nil);
if (!CGImageDestinationFinalize(destination)) {
NSLog(@"Failed to write image to %@", saveUrl);
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
You can’t perform that action at this time.