如何从iOS扩展中的图像URL获取对PHAsset的引用？

Question

我正在开发一个Apple Photos扩展。我需要从PHAsset获取照片HDR和深度效果标志。这个扩展似乎只给了我一个临时图像文件的URL，而不是对PHAsset的引用。换句话说，我需要从扩展图像URL (或其他方式)获取PHAsset的对象，这样才能获得HDR和深度效果属性。

for item: Any in self.extensionContext!.inputItems {
 let inputItem = item as! NSExtensionItem
 for provider: Any in inputItem.attachments! {
      let itemProvider = provider as! NSItemProvider
  if itemProvider.hasItemConformingToTypeIdentifier(kUTTypeImage as String) { ......

非常感谢,

皮尤什

Answer 1

据我所知，深度(100%)和HDR (不确定:P)在图像属性中。因此，请执行以下操作来获取它们：

let options = PHContentEditingInputRequestOptions()
//for icloud or itunes
options.isNetworkAccessAllowed = true

//self is the PHAsset Object here this snippet is from an extenstion I made.            
self.requestContentEditingInput(with: options, completionHandler: {
                (contentEditingInput, _) -> Void in
     if contentEditingInput != nil {
         if let url = contentEditingInput?.fullSizeImageURL {
         //URL is the path of the File in the 
             if let imageSource = CGImageSourceCreateWithURL(url, nil) {
                 if let imageProperties = CGImageSourceCopyPropertiesAtIndex(imageSource, 0, nil) as Dictionary? {
                     //Now you can access the metadata here depth should be in exif afaik
                }
            }
        }
    }
}

可以通过Image I/O的特定常量访问不同的元数据