没有使用ImageIO Framework获取UIImage的更新TIFF数据

Question

我正在使用 ImageIO框架来更新UIImage的元数据然后在我的iphone photoLibrary中保存该图像之后我的问题是我在图像中成功更新了Image TIFF数据但是当我选择该图像时获取TIFF数据然后它不显示TIFF字典数据。在线我可以看到更新的TIFF数据但在我的代码中我看不到它。

更新了TIFF数据：

"{TIFF}" =     {
        Make = "test ";
        Model = test;
        Software = test;
    };

在iOS中获取更新的图像元数据

{
    ColorModel = RGB;
    Depth = 8;
    PixelHeight = 2592;
    PixelWidth = 1936;
    "{PNG}" =     {
        InterlaceType = 0;
    };
}

代码：

 NSData *imageData = UIImagePNGRepresentation(image);
     CGImageSourceRef imageSource = CGImageSourceCreateWithData((__bridge CFDataRef )imageData, NULL);
    if (imageSource == NULL) {
            // Error loading image
            return nil;
        }

    //Set the object in dictinary

    NSMutableDictionary *dict = [[NSMutableDictionary alloc] init];
    NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
                             [NSNumber numberWithBool:NO], (NSString *)kCGImageSourceShouldCache,
                             nil];
    CFDictionaryRef imageProperties = CGImageSourceCopyPropertiesAtIndex(imageSource, 0, (__bridge CFDictionaryRef)options);

//Device name

    CFDictionaryRef refDeviceInfo = CFDictionaryGetValue(imageProperties, kCGImagePropertyTIFFDictionary);
    if (refDeviceInfo) {

        NSString *strMake = (NSString *)CFDictionaryGetValue(refDeviceInfo, kCGImagePropertyTIFFMake);
        NSLog(@"Make: %@", strMake);

        NSString *strModel = (NSString *)CFDictionaryGetValue(refDeviceInfo, kCGImagePropertyTIFFModel);
       NSLog(@"Model: %@", strModel);
  }