Base64圖像編碼Swift 4 iOS

Question

我有以下代碼從庫中選擇一個圖像，然后使用base64encode進行將來的上載...已選擇該圖像並根據需要顯示在應用中...但是在輸出中出現此錯誤

發現擴展時遇到[發現]錯誤：錯誤域= PlugInKit代碼= 13“查詢已取消” UserInfo = {NSLocalizedDescription =查詢已取消}

如果我在輸出中使用打印的base64代碼，並使用網絡工具（ https://www.base64decode.org/ ）嘗試對上述信息進行解碼，以確認其有效，然后再開始在iOS中進行解碼-看來是畸形的嗎？ 我假設我還沒有正確編碼圖像？

 @IBAction func selectImage(_ sender: AnyObject) {


        selectImage.allowsEditing = true //2
        selectImage.sourceType = .photoLibrary //3
        present(selectImage, animated: true, completion: nil)//4


    }

  func imagePickerController(_ selectImage: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {


        let chosenImage = info[UIImagePickerControllerEditedImage] as! UIImage //2

        profilePic.contentMode = .scaleAspectFit //3
        profilePic.image = chosenImage //4

        let quality = 1.0
        base64String = (UIImageJPEGRepresentation(chosenImage, CGFloat(quality))?.base64EncodedString())!
        print (base64String)

        self.dismiss(animated: true, completion: nil) //5
    }

Answer 1

我在我的項目中使用了這兩個函數，並且工作正常。

 func imageTobase64(image: UIImage) -> String {
        var base64String = ""
        let  cim = CIImage(image: image)
        if (cim != nil) {
            let imageData = image.highQualityJPEGNSData
            base64String = imageData.base64EncodedString(options: NSData.Base64EncodingOptions.lineLength64Characters)
        }
        return base64String
    }

    func base64ToImage(base64: String) -> UIImage {
        var img: UIImage = UIImage()
        if (!base64.isEmpty) {
            if let decodedData = Data(base64Encoded: base64 , options: NSData.Base64DecodingOptions.ignoreUnknownCharacters) as Data {
let decodedimage = UIImage(data: decodedData)
            img = (decodedimage as UIImage?)!
}

        }
        return img
    }

我還有一個擴展程序來處理可能有用的圖像質量：

  extension UIImage {
            var highestQualityJPEGNSData:NSData { return UIImageJPEGRepresentation(self, 1.0)! as NSData }
            var highQualityJPEGNSData:NSData    { return UIImageJPEGRepresentation(self, 0.75)! as NSData}
            var mediumQualityJPEGNSData:NSData  { return UIImageJPEGRepresentation(self, 0.5)! as NSData }
            var lowQualityJPEGNSData:NSData     { return UIImageJPEGRepresentation(self, 0.25)! as NSData}
            var lowestQualityJPEGNSData:NSData  { return UIImageJPEGRepresentation(self, 0.0)! as NSData }
        }

//對於Swift 4.2-修改后的擴展

extension UIImage {
    var highestQualityJPEGNSData:NSData { return self.jpegData(compressionQuality: 1.0)! as NSData }
    var highQualityJPEGNSData:NSData    { return self.jpegData(compressionQuality: 0.75)! as NSData}
    var mediumQualityJPEGNSData:NSData  { return self.jpegData(compressionQuality: 0.5)! as NSData }
    var lowQualityJPEGNSData:NSData     { return self.jpegData(compressionQuality: 0.25)! as NSData}
    var lowestQualityJPEGNSData:NSData  { return self.jpegData(compressionQuality: 0.0)! as NSData }
}