Objectivec 从 UIImage 获取 Exif 数据 UIImagePickerController

我找到了解决办法，并从here人那里得到了答案

从这里我们还可以获得GPS信息..

太棒了，谢谢大家帮我解决这个问题.

UPDATE

这是我自己创建的另一个函数，也返回Exif数据以及GPS数据，在这个函数中，我们不需要任何第三方库..但你必须为此打开定位服务.使用当前的纬度和经度.所以必须使用CoreLocation.framework

//FOR CAMERA IMAGE

-(NSMutableData *)getImageWithMetaData:(UIImage *)pImage
{
    NSData* pngData =  UIImagePNGRepresentation(pImage);

    CGImageSourceRef source = CGImageSourceCreateWithData((CFDataRef)pngData, NULL);
    NSDictionary *metadata = (NSDictionary *) CGImageSourceCopyPropertiesAtIndex(source, 0, NULL);

    NSMutableDictionary *metadataAsMutable = [[metadata mutableCopy]autorelease];
    [metadata release];

    //For GPS Dictionary
    NSMutableDictionary *GPSDictionary = [[[metadataAsMutable objectForKey:(NSString *)kCGImagePropertyGPSDictionary]mutableCopy]autorelease];
    if(!GPSDictionary) 
        GPSDictionary = [NSMutableDictionary dictionary];

    [GPSDictionary setValue:[NSNumber numberWithDouble:currentLatitude] forKey:(NSString*)kCGImagePropertyGPSLatitude];
    [GPSDictionary setValue:[NSNumber numberWithDouble:currentLongitude] forKey:(NSString*)kCGImagePropertyGPSLongitude];

    NSString* ref;
    if (currentLatitude <0.0)
        ref = @"S"; 
    else
        ref =@"N";  
    [GPSDictionary setValue:ref forKey:(NSString*)kCGImagePropertyGPSLatitudeRef];

    if (currentLongitude <0.0)
        ref = @"W"; 
    else
        ref =@"E";  
    [GPSDictionary setValue:ref forKey:(NSString*)kCGImagePropertyGPSLongitudeRef];

    [GPSDictionary setValue:[NSNumber numberWithFloat:location.altitude] forKey:(NSString*)kCGImagePropertyGPSAltitude];

    //For EXIF Dictionary
    NSMutableDictionary *EXIFDictionary = [[[metadataAsMutable objectForKey:(NSString *)kCGImagePropertyExifDictionary]mutableCopy]autorelease];
    if(!EXIFDictionary) 
        EXIFDictionary = [NSMutableDictionary dictionary];

    [EXIFDictionary setObject:[NSDate date] forKey:(NSString*)kCGImagePropertyExifDateTimeOriginal];
    [EXIFDictionary setObject:[NSDate date] forKey:(NSString*)kCGImagePropertyExifDateTimeDigitized];

    //add our modified EXIF data back into the image’s metadata
    [metadataAsMutable setObject:EXIFDictionary forKey:(NSString *)kCGImagePropertyExifDictionary];
    [metadataAsMutable setObject:GPSDictionary forKey:(NSString *)kCGImagePropertyGPSDictionary];

    CFStringRef UTI = CGImageSourceGetType(source);

    NSMutableData *dest_data = [NSMutableData data];
    CGImageDestinationRef destination = CGImageDestinationCreateWithData((CFMutableDataRef)dest_data, UTI, 1, NULL);

    if(!destination)
        dest_data = [[pngData mutableCopy] autorelease];
    else 
    {
        CGImageDestinationAddImageFromSource(destination, source, 0, (CFDictionaryRef) metadataAsMutable);
        BOOL success = CGImageDestinationFinalize(destination);
        if(!success)
            dest_data = [[pngData mutableCopy] autorelease];
    }

    if(destination)
        CFRelease(destination);

    CFRelease(source);

    return dest_data;
}

//FOR PHOTO LIBRARY IMAGE

-(NSMutableData *)getImagedataPhotoLibrary:(NSDictionary *)pImgDictionary andImage:(UIImage *)pImage
{
    NSData* data = UIImagePNGRepresentation(pImage);

    CGImageSourceRef source = CGImageSourceCreateWithData((CFDataRef)data, NULL);
    NSMutableDictionary *metadataAsMutable = [[pImgDictionary mutableCopy]autorelease];

    CFStringRef UTI = CGImageSourceGetType(source);

    NSMutableData *dest_data = [NSMutableData data];

    //For Mutabledata
    CGImageDestinationRef destination = CGImageDestinationCreateWithData((CFMutableDataRef)dest_data, UTI, 1, NULL);

    if(!destination)
        dest_data = [[data mutableCopy] autorelease];
    else 
    {
        CGImageDestinationAddImageFromSource(destination, source, 0, (CFDictionaryRef) metadataAsMutable);
        BOOL success = CGImageDestinationFinalize(destination);
        if(!success)
            dest_data = [[data mutableCopy] autorelease];
    }
    if(destination)
        CFRelease(destination);

    CFRelease(source);

    return dest_data;
}

我们将像这样检索数据

//FOR CAMERA IMAGE
NSData *originalImgData = [self getImageWithMetaData:imgOriginal];

//FOR PHOTO LIBRARY IMAGE
[self getImagedataPhotoLibrary:[[myasset defaultRepresentation] metadata] andImage:imgOriginal];

对于所有这些，你应该输入AssetsLibrary.framework和ImageIO.framework.