Losing image orientation while converting an image to CGImage

ios swift uiimage cgimage
Robert Brax picture Robert Brax · Feb 12, 2015 · Viewed 15.8k times · Source

I'm facing an image orientation issue when cropping a square portion of an image out of a rectangular original image. When image is in landscape, it's fine. But when it is in portrait, it seems that the image orientation is not preserved, which result in an image with wrong orientation AND bad crop:

 func cropImage(cropRectangleCoordinates: CGRect) {

        let croppedImage = originalImage

        let finalCroppedImage : CGImageRef = CGImageCreateWithImageInRect(croppedImage.CGImage, cropRectangleCoordinates)

        finalImage =  UIImage(CGImage: finalCroppedImage)!


    }

I think the problem is with croppedImage.CGImage. Here the image gets converted to CGImage, but it seems not to preserve the orientation. It's easy to preserve orientation by using UIImage only, but to make the crop, image needs to be temporarily CGImage and this is the problem. Even if I reorient the image when converting back to UIImage, it might be in the correct orientation but the damage is already done when cropping CGImage.

This is a swift question, so please answer in swift, as the solution can be different in Objective-C.

Answer

Adnan Yusuf picture Adnan Yusuf · Jan 10, 2017

SWIFT 3:

convert rotated cgImage to UIImage by this method 

UIImage(cgImage:croppedCGImage, scale:originalImage.scale, orientation:originalImage.imageOrientation)

Source @David Berry answer

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