將 UIImage 轉(zhuǎn)換為 CIImage

CIImage  *ciImage = [UIImage imageNamed:@"test.png"].CIImage；

將 CIImage 轉(zhuǎn)換為 UIImage

UIImage * image = [UIImage imageWithCIImage:ciimage];

圖片轉(zhuǎn)成 Base 64 編碼

//UIImage圖片轉(zhuǎn)成Base64字符串：
UIImage *originImage = [UIImage imageNamed:@"originImage.png"];
NSData *data = UIImageJPEGRepresentation(originImage, 1.0f);
NSString *encodedImageStr = [data base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];

//Base64字符串轉(zhuǎn)UIImage圖片：
NSData *decodedImageData = [[NSData alloc] 
initWithBase64EncodedString:encodedImageStr options:NSDataBase64DecodingIgnoreUnknownCharacters];
UIImage *decodedImage = [UIImage imageWithData:decodedImageData];