ios - UIImage 调整纵横比填充和裁剪

Question

我有这段代码，我拍了一张尺寸为 2448x3264 的照片，我需要调整大小并调整为左上角的屏幕显示。对不起我的英语谢谢

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{

    imagenUsr = [info objectForKey:UIImagePickerControllerOriginalImage];

    NSLog(@"%f",imagenUsr.size.height);   //2448px
    NSLog(@"%f",imagenUsr.size.width);   //3264px


}

我需要调整到 320x568 宽高比以填充拍摄图像的顶部和左侧

Answer 1

swift 3.0/4.0

AspectFill 图像裁剪/调整大小...根据 UIImageview 帧大小。

    func ResizeImage(with image: UIImage?, scaledToFill size: CGSize) -> UIImage? {
    let scale: CGFloat = max(size.width / (image?.size.width ?? 0.0), size.height / (image?.size.height ?? 0.0))
    let width: CGFloat = (image?.size.width ?? 0.0) * scale
    let height: CGFloat = (image?.size.height ?? 0.0) * scale
    let imageRect = CGRect(x: (size.width - width) / 2.0, y: (size.height - height) / 2.0, width: width, height: height)
    UIGraphicsBeginImageContextWithOptions(size, false, 0)
    image?.draw(in: imageRect)
    let newImage: UIImage? = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()
    return newImage
}