Swift PNG 图像以不正确的方向保存

Swift PNG 图像以不正确的方向保存

swift
import UIKit
import ImageIO
func fixPNGImageOrientation(image: UIImage) -> UIImage? {
    guard let cgImage = image.cgImage else {
        return nil
    }
    
    let orientation = image.imageOrientation
    
    guard let data = image.pngData(),
          let source = CGImageSourceCreateWithData(data as CFData, nil),
          let type = CGImageSourceGetType(source) else {
        return nil
    }
    
    let options: [CFString: Any] = [
        kCGImageSourceShouldCache: false,
        kCGImageSourceShouldAllowFloat: true,
        kCGImageSourceCreateThumbnailFromImageAlways: true,
        kCGImageSourceCreateThumbnailWithTransform: true,
        kCGImageSourceThumbnailMaxPixelSize: max(image.size.width, image.size.height)
    ]
    
    guard let thumbnail = CGImageSourceCreateThumbnailAtIndex(source, 0, options as CFDictionary) else {
        return nil
    }
    
    let fixedCGImage: CGImage
    
    switch orientation {
    case .up, .upMirrored:
        fixedCGImage = thumbnail
    case .down, .downMirrored:
        fixedCGImage = thumbnail.rotate(radians: .pi)
    case .left, .leftMirrored:
        fixedCGImage = thumbnail.rotate(radians: .pi / 2)
    case .right, .rightMirrored:
        fixedCGImage = thumbnail.rotate(radians: -.pi / 2)
    @unknown default:
        fixedCGImage = thumbnail
    }
    
    let fixedImage = UIImage(cgImage: fixedCGImage, scale: image.scale, orientation: .up)
    
    return fixedImage
}