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- (UIImage *)combineImage:(UIImage *)imageA imageB:(UIImage *)imageB {
    UIGraphicsBeginImageContext(imageA.size);

    [imageA drawInRect:CGRectMake(0, 0, imageA.size.width, imageA.size.height)];
    [imageB drawInRect:CGRectMake(0, 0, imageB.size.width, imageB.size.height)];

    UIImage *combinatedImage = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return combinatedImage;
}

#define kAppIconWidth 84
#define kAppIconHeight 66

// In image un nostro puntatore UIImage *image

if (image.size.width > kAppIconWidth || image.size.height > kAppIconHeight) {
    CGSize itemSize = CGSizeMake(kAppIconWidth, kAppIconHeight);
    UIGraphicsBeginImageContext(itemSize);
    CGRect imageRect = CGRectMake(0.0, 0.0, itemSize.width, itemSize.height);
    [image drawInRect:imageRect];
    UIImage *resizeImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
}

- (UIImage *)cropImage:(UIImage *)image cropRect:(CGRect)rect {
    CGImageRef sourceImageRef = [image CGImage];
    CGImageRef newImageRef = CGImageCreateWithImageInRect(sourceImageRef, rect);
    UIImage *newImage = [UIImage imageWithCGImage:newImageRef];
    return newImage;
}