有人知道如何将一个UIImage转换为Base64字符串,然后反转它吗?

我有以下代码;编码前的原始图像是好的,但编码解码后只得到一个空白图像。

NSData *imageData = UIImagePNGRepresentation(viewImage);

NSString *b64EncStr = [self encode: imageData];

NSString *base64String = [self encodeBase64:imageData];

当前回答

对于iOS 7+, Objective-C,下面是如何从一个图像URL开始转换:

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

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

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

其他回答

Swift 3.0和Xcode 8.0

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

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

斯威夫特5号,Xcode 10号。

let imageData = UIImage(named:“imagename”).pngData()?.base64EncodedString(选项: .lineLength64Characters) 打印(图像数据)

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)
    }
}

斯威夫特4

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)
    }
}
@implementation UIImage (Extended)

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

@end