关于ios：在UIImage和Base64字符串之间进行转换


Convert between UIImage and Base64 string

是否有人知道如何将UIImage转换为base64字符串，然后将其反转？

我有下面的代码；编码前的原始图像是好的，但是我只有在编码和解码后才能得到空白图像。

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NSData *imageData = UIImagePNGRepresentation(viewImage);

NSString *b64EncStr = [self encode: imageData];

NSString *base64String = [self encodeBase64:imageData];
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迅捷

首先我们需要图像的nsdata

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//Use image name from bundle to create NSData
let image : UIImage = UIImage(named:"imageNameHere")!
//Now use image to create into NSData format
let imageData:NSData = UIImagePNGRepresentation(image)!

//OR next possibility

//Use image's path to create NSData
let url:NSURL = NSURL(string :"urlHere")!
//Now use image to create into NSData format
let imageData:NSData = NSData.init(contentsOfURL: url)!

Swift 2.0>编码

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let strBase64:String = imageData.base64EncodedStringWithOptions(.Encoding64CharacterLineLength)

Swift 2.0>解码

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let dataDecoded:NSData = NSData(base64EncodedString: strBase64, options: NSDataBase64DecodingOptions.IgnoreUnknownCharacters)!

Swift 3.0>解码

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let dataDecoded : Data = Data(base64Encoded: strBase64, options: .ignoreUnknownCharacters)!

编码：

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let strBase64 = imageData.base64EncodedString(options: .lineLength64Characters)
print(strBase64)

解码：

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let dataDecoded:NSData = NSData(base64EncodedString: strBase64, options: NSDataBase64DecodingOptions(rawValue: 0))!
let decodedimage:UIImage = UIImage(data: dataDecoded)!
print(decodedimage)
yourImageView.image = decodedimage

斯威夫特3

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let dataDecoded : Data = Data(base64Encoded: strBase64, options: .ignoreUnknownCharacters)!
let decodedimage = UIImage(data: dataDecoded)
yourImageView.image = decodedimage

Objtovi-CiOS7>版本

您可以使用NSData'sbase64EncodedStringWithOptions。

编码：

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- (NSString *)encodeToBase64String:(UIImage *)image {
 return [UIImagePNGRepresentation(image) base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
}

解码：

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- (UIImage *)decodeBase64ToImage:(NSString *)strEncodeData {
  NSData *data = [[NSData alloc]initWithBase64EncodedString:strEncodeData options:NSDataBase64DecodingIgnoreUnknownCharacters];
  return [UIImage imageWithData:data];
}

iOS 6.1及以下版本

第一个选项：使用指向encode和decode映像的链接

在您的project中添加base64类。

编码：

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 NSData* data = UIImageJPEGRepresentation(yourImage, 1.0f);
 NSString *strEncoded = [Base64 encode:data];

解码：

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 NSData* data = [Base64 decode:strEncoded ];;
 image.image = [UIImage imageWithData:data];

另一种选择：对encoding和decoding使用qsutilities

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Swift 4.2扩展方法

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extension UIImage {
    func toBase64() -> String? {
        guard let imageData = self.pngData() else { return nil }
        return imageData.base64EncodedString(options: Data.Base64EncodingOptions.lineLength64Characters)
    }
}

Xcode 9.1和Swift 4.0

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//
// Convert UIImage to a base64 representation
//
class func convertImageToBase64(image: UIImage) -> String {
    let imageData = UIImagePNGRepresentation(image)!
    return imageData.base64EncodedString(options: Data.Base64EncodingOptions.lineLength64Characters)
}

//
// Convert a base64 representation to a UIImage
//
class func convertBase64ToImage(imageString: String) -> UIImage {
    let imageData = Data(base64Encoded: imageString, options: Data.Base64DecodingOptions.ignoreUnknownCharacters)!
    return UIImage(data: imageData)!
}

Swift 3.0，Xcode 8.0

用URL替换字符串。测试图像是图像视图的一个出口

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// Put Your Image URL
let url:NSURL = NSURL(string :"http://.jpg")!
// It Will turn Into Data
let imageData : NSData = NSData.init(contentsOf: url as URL)!
// Data Will Encode into Base64
let str64 = imageData.base64EncodedData(options: .lineLength64Characters)
// Now Base64 will Decode Here
let data: NSData = NSData(base64Encoded: str64 , options: .ignoreUnknownCharacters)!
// turn  Decoded String into Data
let dataImage = UIImage(data: data as Data)
// pass the data image to image View.:)
testImage.image = dataImage

希望能有所帮助，谢谢。

斯威夫特IOS8

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// prgm mark ----

// convert images into base64 and keep them into string

func convertImageToBase64(image: UIImage) -> String {

    var imageData = UIImagePNGRepresentation(image)
    let base64String = imageData.base64EncodedStringWithOptions(.allZeros)

    return base64String

}// end convertImageToBase64


// prgm mark ----

// convert images into base64 and keep them into string

func convertBase64ToImage(base64String: String) -> UIImage {

    let decodedData = NSData(base64EncodedString: base64String, options: NSDataBase64DecodingOptions(rawValue: 0) )

    var decodedimage = UIImage(data: decodedData!)

    return decodedimage!

}// end convertBase64ToImage

斯威夫特3

将图像转换为base64字符串

操场测试

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    var logo = UIImage(named:"image_logo")
    let imageData:Data =  UIImagePNGRepresentation(logo)
    let base64String = imageData.base64EncodedString()
    print(base64String)
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@implementation UIImage (Extended)

- (NSString *)base64String {
    NSData * data = [UIImagePNGRepresentation(self) base64EncodedDataWithOptions:NSDataBase64Encoding64CharacterLineLength];
    return [NSString stringWithUTF8String:[data bytes]];
}

@end
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在Swift 2.0中使用此扩展名(贷记给Jonas Franz)

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extension UIImage{
  func toBase64() -> String{
    let imageData = UIImagePNGRepresentation(self)!
    return imageData.base64EncodedStringWithOptions(.Encoding64CharacterLineLength)
  }
}
在Swift 3.0和Xcode 8.0中编码：

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let userImage:UIImage = UIImage(named:"Your-Image_name")!
let imageData:NSData = UIImagePNGRepresentation(userImage)! as NSData
let dataImage = imageData.base64EncodedString(options: .lineLength64Characters)

解码：

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let imageData = dataImage
let dataDecode:NSData = NSData(base64Encoded: imageData!, options:.ignoreUnknownCharacters)!
let avatarImage:UIImage = UIImage(data: dataDecode as Data)!
yourImageView.image = avatarImage
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斯威夫特5

编码

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func ConvertImageToBase64String (img: UIImage) -> String {
    return img.jpegData(compressionQuality: 1)?.base64EncodedString() ??""
}

译码

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func ConvertBase64StringToImage (imageBase64String:String) -> UIImage {
    let imageData = Data.init(base64Encoded: imageBase64String, options: .init(rawValue: 0))
    let image = UIImage(data: imageData!)
    return image!
}

Note: Tested in xcode 10.2

斯威夫特4

编码

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func ConvertImageToBase64String (img: UIImage) -> String {
    let imageData:NSData = UIImageJPEGRepresentation(img, 0.50)! as NSData //UIImagePNGRepresentation(img)
    let imgString = imageData.base64EncodedString(options: .init(rawValue: 0))
    return imgString
}

译码

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func ConvertBase64StringToImage (imageBase64String:String) -> UIImage {
    let imageData = Data.init(base64Encoded: imageBase64String, options: .init(rawValue: 0))
    let image = UIImage(data: imageData!)
    return image
}

Note: Tested in xcode 9.4.1

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SWIFT扩展：

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extension UIImage{
     func toBase64() -> String{
          var imageData = UIImagePNGRepresentation(self)
          return imageData.base64EncodedStringWithOptions(.allZeros)
     }
}
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斯威夫特4

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enum ImageFormat {
    case png
    case jpeg(CGFloat)
}

extension UIImage {
    func base64(format: ImageFormat) -> String? {
        var imageData: Data?

        switch format {
        case .png: imageData = UIImagePNGRepresentation(self)
        case .jpeg(let compression): imageData = UIImageJPEGRepresentation(self, compression)
        }

        return imageData?.base64EncodedString()
    }
}

extension String {
    func imageFromBase64() -> UIImage? {
        guard let data = Data(base64Encoded: self) else { return nil }

        return UIImage(data: data)
    }
}

Swift版本-为图像创建base64

在我看来，在UIImagePNGRepresenatation()的情况下，隐式展开的可选方案是不安全的，因此我建议使用如下扩展：

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extension UIImage {

    func toBase64() -> String? {
        let imageData = UIImagePNGRepresentation(self)
        return imageData?.base64EncodedStringWithOptions(NSDataBase64EncodingOptions.Encoding64CharacterLineLength)
    }
}

我尝试了所有的解决方案，没有一个对我有效(使用swift 4)，这是对我有效的解决方案，如果将来有人面临同样的问题。

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let temp = base64String.components(separatedBy:",")
let dataDecoded : Data = Data(base64Encoded: temp[1], options:
 .ignoreUnknownCharacters)!
let decodedimage = UIImage(data: dataDecoded)

yourImage.image = decodedimage
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See my class -  AppExtension.swift


// MARK: - UIImage (Base64 Encoding)

public enum ImageFormat {
    case PNG
    case JPEG(CGFloat)
}

extension UIImage {

    public func base64(format: ImageFormat) -> String {
        var imageData: NSData
        switch format {
        case .PNG: imageData = UIImagePNGRepresentation(self)
        case .JPEG(let compression): imageData = UIImageJPEGRepresentation(self, compression)
        }
        return imageData.base64EncodedStringWithOptions(.allZeros)
    }
}

Swift 4.2_xcode 10

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extension UIImage {

    /// EZSE: Returns base64 string
    public var base64: String {
        return self.jpegData(compressionQuality: 1.0)!.base64EncodedString()
    }
}

在斯威夫特3

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func decodeBase64(toImage strEncodeData: String) -> UIImage {

    let dataDecoded  = NSData(base64Encoded: strEncodeData, options: NSData.Base64DecodingOptions.ignoreUnknownCharacters)!
    let image = UIImage(data: dataDecoded as Data)
    return image!

}

Swift 5，Xcode 10.

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 let imageData = UIImage(named:"imagename").pngData()?.base64EncodedString(options: .lineLength64Characters)

print(imageData)

Swift 3.0和Xcode 8.0

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let imageData = UIImageJPEGRepresentation(imageView.image!, 1)

    let base64String = (imageData! as Data).base64EncodedString(options: NSData.Base64EncodingOptions(rawValue: 0))
    print(base64String)

对于iOS 7+、Objective-C，下面介绍如何从图像URL开始转换：

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NSURL *url = [NSURL URLWithString:self.groove.thumbnailURL];

UIImage *image = [UIImage imageWithData:[NSData dataWithContentsOfURL:url]];

NSString *base64String = [UIImagePNGRepresentation(image)
base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];