How to combine/ merge 2 images into 1

Question

I would like to know what to do to save 2 images into 1 image.

One of the photos can be moved, rotated and zoomed in/out...

I\'m doing this, but it basically

Answer 1

You can create graphics context and draw both images in it. You'll get an image result from both your source images combined.

- (UIImage*)imageByCombiningImage:(UIImage*)firstImage withImage:(UIImage*)secondImage {
    UIImage *image = nil;

    CGSize newImageSize = CGSizeMake(MAX(firstImage.size.width, secondImage.size.width), MAX(firstImage.size.height, secondImage.size.height));
    if (UIGraphicsBeginImageContextWithOptions != NULL) {
        UIGraphicsBeginImageContextWithOptions(newImageSize, NO, [[UIScreen mainScreen] scale]);
    } else {
        UIGraphicsBeginImageContext(newImageSize); 
    }
    [firstImage drawAtPoint:CGPointMake(roundf((newImageSize.width-firstImage.size.width)/2), 
                                        roundf((newImageSize.height-firstImage.size.height)/2))]; 
    [secondImage drawAtPoint:CGPointMake(roundf((newImageSize.width-secondImage.size.width)/2), 
                                         roundf((newImageSize.height-secondImage.size.height)/2))]; 
    image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    return image;
}

Answer 2

Swift 3

In this example the frontImage is being drawn inside the other image using a insetBy of 20% margin.

The background image must be drawn before and then the front image in sequence.

I used this to place a "Play" icon image in front a video frame image inside a UIImageView like below:

Usage:

self.image = self.mergedImageWith(frontImage: UIImage.init(named: "play.png"), backgroundImage: UIImage.init(named: "backgroundImage.png")))

Method:

func mergedImageWith(frontImage:UIImage?, backgroundImage: UIImage?) -> UIImage{

    if (backgroundImage == nil) {
        return frontImage!
    }

    let size = self.frame.size
    UIGraphicsBeginImageContextWithOptions(size, false, 0.0)

    backgroundImage?.draw(in: CGRect.init(x: 0, y: 0, width: size.width, height: size.height))
    frontImage?.draw(in: CGRect.init(x: 0, y: 0, width: size.width, height: size.height).insetBy(dx: size.width * 0.2, dy: size.height * 0.2))

    let newImage:UIImage = UIGraphicsGetImageFromCurrentImageContext()!
    UIGraphicsEndImageContext()

    return newImage
}