从iOS图像中提取的GPS值未显示正确的正面或负面

我正在开发一个iPhone应用程序,它将从拍摄的照片中提取GPS数据.我已经为这个功能做了很好的工作,但我注意到返回的GPS数据没有显示正确的+或-坐标值.例如,我在日志中获得此输出:

"{GPS}" =     {
    Altitude = "33.0329";
    DOP = 65;
    Latitude = "64.84069";
    LatitudeRef = N;
    Longitude = "32.41367";
    LongitudeRef = W;
    TimeStamp = "2014:01:04 14:47:01";
};

当我使用纬度和经度并使用反向地理定位映射时,我会在世界的另一边找到一些位置.在调查之后,我看到了价值:

Longitude = "32.41367";

应该:

Longitude = "-32.41367";

它只是错过了消极的.关于为什么会发生这种情况的任何想法？以下是构建上述输出的一些代码示例:

    UIImage *image =  [info objectForKey:UIImagePickerControllerOriginalImage];
    NSData *jpeg = UIImageJPEGRepresentation(image,image.scale);
    CGImageSourceRef source = CGImageSourceCreateWithData((__bridge CFDataRef)jpeg, NULL);
    NSDictionary *metadata = (__bridge NSDictionary *)CGImageSourceCopyPropertiesAtIndex(source,0,NULL);
    NSMutableDictionary *mutableMetadata = [metadata mutableCopy];

    [mutableMetadata setLocation:self.currentLocation];

    CFStringRef UTI = CGImageSourceGetType(source);
    NSMutableData *data = [NSMutableData data];
    CGImageDestinationRef destination = CGImageDestinationCreateWithData((__bridge CFMutableDataRef) data, UTI, 1, NULL);
    CGImageDestinationAddImageFromSource(destination,source, 0, (__bridge CFDictionaryRef) mutableMetadata);
    BOOL success = CGImageDestinationFinalize(destination);

    NSLog(@"This is the log value that was referenced above: %@",mutableMetadata);

Martijn.. 5

N和E具有正值S和W具有负值

但是,如果您只是将参考文献放在坐标中,Google地图就知道如何映射它们.例如,在Google地图(50.53467,-100.45646)中等于N50.53467W100.45646