title: How to read "{TIFF}" information inside the metadata of a taken picture
body: <p>I am a newbie in objective-c and I have problems reading information in the UIImagePickerControllerMediaMetaData. </p>
  
  <pre><code>-(void) imagePickerController:(UIImagePickerController *)imagepicker didFinishPickingMediaWithInfo:(NSDictionary *)info {
  
  //This line is fine.
  NSDictionary *metadata = [info objectForKey:UIImagePickerControllerMediaMetadata];
  
  //This line fail to operate...
  NSArray *tiffData = [metadata objectForKey:Exif];
  </code></pre>
  
  <p>I can get the metadata. However, the info inside metadata is a little bit confusing and below shows what inside metadata.</p>
  
  <pre><code>UIImagePickerControllerMediaMetadata =     {
      DPIHeight = 72;
      DPIWidth = 72;
      Orientation = 6;
      "{Exif}" =         {
          ApertureValue = "2.526068811667588";
          BrightnessValue = "-1.739497174308802";
          ColorSpace = 1;
          DateTimeDigitized = "2012:02:21 11:53:44";
          DateTimeOriginal = "2012:02:21 11:53:44";
          ExposureMode = 0;
          ExposureProgram = 2;
          ExposureTime = "0.06666666666666667";
          FNumber = "2.4";
          Flash = 32;
          FocalLenIn35mmFilm = 32;
          FocalLength = "2.03";
          ISOSpeedRatings =             (
              800
          );
          MeteringMode = 5;
          PixelXDimension = 960;
          PixelYDimension = 720;
          SceneType = 1;
          SensingMethod = 2;
          Sharpness = 0;
          ShutterSpeedValue = "3.906905022631062";
          WhiteBalance = 0;
      };
      "{TIFF}" =         {
          DateTime = "2012:02:21 11:53:44";
          Make = Apple;
          Model = "iPad 2";
          Software = "5.0.1";
          XResolution = 72;
          YResolution = 72;
      };
  };
  </code></pre>
  
  <p>So how can I read the "{Exif}" and the "{TIFF}"? </p>
  
  <p>Thanks for helping me. I found everywhere and just failed to get an answer...</p>