我有一个我正在处理的应用程序,它具有允许用户拍照或从照片库中选择图像的功能。代码有效,但图像始终显示大于UIImageView
框。该框在故事板中设置为“缩放纵横比”,但摄像机图像拒绝符合。
以下是代码:
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
if let chosenImage = info[UIImagePickerControllerOriginalImage] as? UIImage{
imageField.image = chosenImage
} else{
//error message goes here
}
self.dismiss(animated: true, completion: nil)
}
如何让chosenImage
符合方框或方位?
答案 0 :(得分:0)
请尝试这种方式:
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
if let chosenImage = info[UIImagePickerControllerOriginalImage] as? UIImage{
imageField.image = chosenImage
imageField.contentMode = UIViewContentMode.scaleToFill
imageField.clipsToBounds = true
} else{
//error message goes here
}
self.dismiss(animated: true, completion: nil)
}
为什么ScaleAspectFill
和clipsToBounds = true
会看到这个问题Why scale to fill give bigger image than UIImageVIew size? (using swift)
如果您想要更多学习,请查看此How to scale a UIImageView proportionally?
答案 1 :(得分:0)
以下代码将调整与swift 4.0兼容的相机拍摄图像的大小。
它使用UIImageOrientaiton检查图像的EXIF属性,并根据方向值进行调整,对图像进行变换和缩放,以便获得与相机视图方向相同的返回图像。
func scaleAndRotateImage(image: UIImage, MaxResolution iIntMaxResolution: Int) -> UIImage {
let kMaxResolution = iIntMaxResolution
let imgRef = image.cgImage!
let width: CGFloat = CGFloat(imgRef.width)
let height: CGFloat = CGFloat(imgRef.height)
var transform = CGAffineTransform.identity
var bounds = CGRect.init(x: 0, y: 0, width: width, height: height)
if Int(width) > kMaxResolution || Int(height) > kMaxResolution {
let ratio: CGFloat = width / height
if ratio > 1 {
bounds.size.width = CGFloat(kMaxResolution)
bounds.size.height = bounds.size.width / ratio
}
else {
bounds.size.height = CGFloat(kMaxResolution)
bounds.size.width = bounds.size.height * ratio
}
}
let scaleRatio: CGFloat = bounds.size.width / width
let imageSize = CGSize.init(width: CGFloat(imgRef.width), height: CGFloat(imgRef.height))
var boundHeight: CGFloat
let orient = image.imageOrientation
// The output below is limited by 1 KB.
// Please Sign Up (Free!) to remove this limitation.
switch orient {
case .up:
//EXIF = 1
transform = CGAffineTransform.identity
case .upMirrored:
//EXIF = 2
transform = CGAffineTransform.init(translationX: imageSize.width, y: 0.0)
transform = transform.scaledBy(x: -1.0, y: 1.0)
case .down:
//EXIF = 3
transform = CGAffineTransform.init(translationX: imageSize.width, y: imageSize.height)
transform = transform.rotated(by: CGFloat(Double.pi / 2))
case .downMirrored:
//EXIF = 4
transform = CGAffineTransform.init(translationX: 0.0, y: imageSize.height)
transform = transform.scaledBy(x: 1.0, y: -1.0)
case .leftMirrored:
//EXIF = 5
boundHeight = bounds.size.height
bounds.size.height = bounds.size.width
bounds.size.width = boundHeight
transform = CGAffineTransform.init(translationX: imageSize.height, y: imageSize.width)
transform = transform.scaledBy(x: -1.0, y: 1.0)
transform = transform.rotated(by: CGFloat(Double.pi / 2) / 2.0)
break
default: print("Error in processing image")
}
UIGraphicsBeginImageContext(bounds.size)
let context = UIGraphicsGetCurrentContext()
if orient == .right || orient == .left {
context?.scaleBy(x: -scaleRatio, y: scaleRatio)
context?.translateBy(x: -height, y: 0)
}
else {
context?.scaleBy(x: scaleRatio, y: -scaleRatio)
context?.translateBy(x: 0, y: -height)
}
context?.concatenate(transform)
context?.draw(imgRef, in: CGRect.init(x: 0, y: 0, width: width, height: height))
let imageCopy = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return imageCopy!
}