Perspective correction of UIImage from Points

Question

I\'m working on a app where I\'ll let the user take a picture e.g of a business card or photograph.

The user will then mark the four corners of the object (which the

Answer 1

From iOS8+ there is Filter for Core Image called CIPerspectiveCorrection. All you need to do is pass the image and four points.

Also there is one more filter supporting iOS6+ called CIPerspectiveTransform which can be used in similar way (skewing image).