UIImageView cropping square - ios

Question

First of all, my app asks the user to pick a photo from collectionview or taken camera pictures, then navigate to cropping image editor, so that our final image will be square according to cropping area position.But, the problem is there is few source detail about it. Without UIImagePicker, how is to be done?
I also tried taking square picture, with no success.
I implemented UIPinchGesture imageview so that user can zoom in or out, but there is no cropping square on the image view. I have to add cropping area.
This is cropping UIImage function:
func croppImageByRect() -> UIImage {
let ratio: CGFloat = 1 // square
let delta: CGFloat
let offSet: CGPoint
//make a new square size, that is the resized imaged width
let newSize = CGSizeMake(size.width, (size.width - size.width / 8))
//figure out if the picture is landscape or portrait, then
//calculate scale factor and offset
if (size.width > size.height) {
delta = (ratio * size.width - ratio * size.height)
offSet = CGPointMake(delta / 2, 0)
} else {
delta = (ratio * size.height - ratio * size.width)
offSet = CGPointMake(0, delta / 2)
}
//make the final clipping rect based on the calculated values
let clipRect = CGRectMake(-offSet.x, -offSet.y, (ratio * size.width) + delta, (ratio * size.height) + delta)
//start a new context, with scale factor 0.0 so retina displays get
//high quality image
UIGraphicsBeginImageContextWithOptions(newSize, true, 0.0)
UIRectClip(clipRect)
drawInRect(clipRect)
let newImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return newImage
}

Answer 1

Well, to start, this line:
// make a new square size, that is the resized imaged width
let newSize = CGSizeMake(size.width, (size.width - size.width / 8))
Will not result in a square size since width and height are not the same.