ios - Swift:HEIC 图像的 PHAssetChangeRequest 失败

Question

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
        }

        //...
    } 

此函数编辑所选图像:

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)")

            })

        })

    }
}

具有示例 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:出于某种原因，当我将 HEIC 图像从 iPhone 发送到 Mac 并将其发送回 iPhone 时，它​​在新副本上运行，它仍然是 HEIC 并保留了原始图像方向。

Answer 1

开始吧，它是这样工作的:创建一个 CGImageDestination，将输出写入 .renderedContentURL，执行 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))")
            })

        })

    }
}