Swift：HEIC 图像的 PHAssetChangeRequest 失败

Posted 2023-03-08

【中文标题】Swift：HEIC 图像的 PHAssetChangeRequest 失败

【英文标题】：Swift: PHAssetChangeRequest fails for HEIC image

【发布时间】：2019-07-29 20:24:09

【问题描述】：

我想对图库中的图像（由 iPhone 相机拍摄）执行编辑，例如 JEPG 压缩，但是当输入图像是 HEIC 图像，但适用于 JPEG 图像。

我通过UIImagePickerController 方法在PHAsset 对象中检索图像：

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) 
        if let asset = info[UIImagePickerController.InfoKey.phAsset] as? PHAsset 
            self.asset = asset
        

        //...
     

这个函数编辑选中的图像：

func editImage() 
if let _asset = self.asset 
        _asset.requestContentEditingInput(with: nil, completionHandler:  (contentEditingInput, info) in
            let fullURL: URL?
            fullURL = contentEditingInput!.fullSizeImageURL

            let output = PHContentEditingOutput(contentEditingInput:
                contentEditingInput!)
            let archivedData = try? NSKeyedArchiver.archivedData(withRootObject: "HEICEditor", requiringSecureCoding: false)
            let adjustmentData =
                PHAdjustmentData(formatIdentifier:
                    "HEICEditor.App",
                                 formatVersion: "1.0",
                                 data: archivedData!)

            output.adjustmentData = adjustmentData
            let imageData = UIImage.init(contentsOfFile: fullURL!.path)?.jpegData(compressionQuality: 0.5)

            do 
                try imageData!.write(to: output.renderedContentURL, options: .atomic)
             catch let error 
                print("error writing data:\(error)")
            

            phphotoLibrary.shared().performChanges(
                let request = PHAssetChangeRequest(for: _asset)
                request.contentEditingOutput = output

            , completionHandler:  (result, error) in
               print("error writing data:\(error)")

            )

        )

    

带有示例HEIC 图像的项目可在https://github.com/maysamsh/Swift-Playground-EditHEIC 获得

注意 1：使用 EXIF 查看器，您可以查看图像是否为 HEIC，或者在选择图像并单击“编辑图像”按钮后，您可以在图像预览顶部看到全名。

注意 2：由于某种原因，当我将 HEIC 图像从 iPhone 发送到 Mac 并将其发送回 iPhone 时，它​​可以在新副本上工作，该副本仍然是 HEIC 并保留原始图像方向。

【参考方案1】：

给你，它是这样工作的：创建一个CGImageDestination，将输出写入.renderedContentURL，执行the PHAssetChangeRequest()：

func editImage() 
    if let _asset = self.asset 
        let options = PHContentEditingInputRequestOptions()
        options.canHandleAdjustmentData = (adjustmeta: PHAdjustmentData)
            -> Bool in
            return true
        
        _asset.requestContentEditingInput(with: options, completionHandler:  (contentEditingInput, info) in
            let fullURL: URL?
            fullURL = contentEditingInput!.fullSizeImageURL
            let output = PHContentEditingOutput(contentEditingInput:
                contentEditingInput!)
            let archivedData = try? NSKeyedArchiver.archivedData(withRootObject: "HEICEditor", requiringSecureCoding: false)
            let adjustmentData =
                PHAdjustmentData(formatIdentifier:
                    "HEICEditor.App",
                                 formatVersion: "1.0",
                                 data: archivedData!)


            let orientation = contentEditingInput?.fullSizeImageOrientation
            let outputURL = output.renderedContentURL
            let cgImage = 
                () -> CGImage in
                let image = UIImage.init(contentsOfFile: fullURL!.path)!
                let imageData = image.jpegData(compressionQuality: 1)
                let ciImage = CIImage(data: imageData!)!.oriented(forExifOrientation: orientation!)

                return CIContext(options: nil).createCGImage(ciImage, from: ciImage.extent)!
            ()

            let cgImageDestination = CGImageDestinationCreateWithURL(outputURL as CFURL, kUTTypeJPEG, 1, nil)!
            CGImageDestinationAddImage(cgImageDestination, cgImage, [
                kCGImageDestinationLossyCompressionQuality as String:0.7
                ] as CFDictionary)
            CGImageDestinationFinalize(cgImageDestination)


            output.adjustmentData = adjustmentData
            self.infoLabel.text = "fullSizeImageURL: \(fullURL?.lastPathComponent ?? "N/A")\n" +
            "renderedContentURL: \(output.renderedContentURL.lastPathComponent)"

            PHPhotoLibrary.shared().performChanges(
                let request = PHAssetChangeRequest(for: _asset)
                request.contentEditingOutput = output
            , completionHandler:  (result, error) in
                print("result: \(result), error: \(String(describing: error))")
            )

        )

    

【讨论】：

kUTTypeJPEG 在哪里？我收到：在范围内找不到“kUTTypeJPEG”。如何导入？

可能需要导入Photos

在文件顶部添加import Photos

不，我使用“public.jpeg”作为字符串解决了。