Convert a UIImage to a CIImage to crop to a CGRect. AVFoundation

Question

So I have a UIImage which I want to crop. I looked and found imageByCroppingToRect method for CIImage. So, I converted the data to CIImage instead of UIImage, crop it using the specified method and then convert the resulting CIImage to UIImage and then display it in a UIImageView.

My code is

 NSData *data = [[NSData alloc]initWithData:[def objectForKey:@"imageData"]];
//UIImage *normalImage = [[UIImage alloc]initWithData:data];
CIImage *originalImage = [CIImage imageWithData:data];
[originalImage imageByCroppingToRect:CGRectMake(10, 72, 300, 300)];

self.imageView.image = [UIImage imageWithCIImage:originalImage];

The problem is the image gets rotated by 90 degrees and I am not sure if it is being cropped. This image is captured using the device's camera. I use AVFoundation to access the camera. My session preset is AVCaptureSessionPresetPhoto. I think this is why I get the zooming.

Answer 1

CGRect rect = CGRectMake(10, 72, 300, 300);
CGImageRef imref = CGImageCreateWithImageInRect([yourOriginalImage CGImage], rect);
UIImage *newSubImage = [UIImage imageWithCGImage:imref];

try this. may help u.

EDIT:

Firstly fix your image orientation: refs : https://github.com/j3r3miah/mapmatic-ios/blob/master/Mapmatic/UIImage+FixOrientation.m

then use above code to crop the Image to Specified Rect.

Answer 2

Not really an answer to your question, but an answer to your problem

https://github.com/mbcharbonneau/UIImage-Categories

especially this file : https://github.com/mbcharbonneau/UIImage-Categories/blob/master/UIImage%2BResize.m

- (UIImage *)croppedImage:(CGRect)bounds {
    CGFloat scale = MAX(self.scale, 1.0f);
    CGRect scaledBounds = CGRectMake(bounds.origin.x * scale, bounds.origin.y * scale, bounds.size.width * scale, bounds.size.height * scale);
    CGImageRef imageRef = CGImageCreateWithImageInRect([self CGImage], scaledBounds);
    UIImage *croppedImage = [UIImage imageWithCGImage:imageRef scale:self.scale orientation:UIImageOrientationUp];
    CGImageRelease(imageRef);
    return croppedImage;
}

you will find there all you need to crop your image