ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
[library assetForURL:[info objectForKey:UIImagePickerControllerReferenceURL]resultBlock:^(ALAsset *asset) {ALAssetRepresentation *image_representation = [asset defaultRepresentation];// create a buffer to hold image datauint8_t *buffer = (Byte*)malloc(image_representation.size);NSUInteger length = [image_representation getBytes:buffer fromOffset: 0.0  length:image_representation.size error:nil];if (length != 0)  {// buffer -> NSData object; free buffer afterwardsNSData *adata = [[NSData alloc] initWithBytesNoCopy:buffer length:image_representation.size freeWhenDone:YES];// identify image type (jpeg, png, RAW file, ...) using UTI hintNSDictionary* sourceOptionsDict = [NSDictionary dictionaryWithObjectsAndKeys:(id)[image_representation UTI] ,kCGImageSourceTypeIdentifierHint,nil];// create CGImageSource with NSDataCGImageSourceRef sourceRef = CGImageSourceCreateWithData((__bridge CFDataRef) adata,  (__bridge CFDictionaryRef) sourceOptionsDict);// get imagePropertiesDictionary
                 CFDictionaryRef imagePropertiesDictionary;imagePropertiesDictionary = CGImageSourceCopyPropertiesAtIndex(sourceRef,0, NULL);// get exif dataCFDictionaryRef exif = (CFDictionaryRef)CFDictionaryGetValue(imagePropertiesDictionary, kCGImagePropertyExifDictionary);NSDictionary *exif_dict = (__bridge NSDictionary*)exif;NSLog(@"exif_dict: %@",exif_dict);// save image WITH meta dataNSString *documentsDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];NSURL *fileURL = nil;CGImageRef imageRef = CGImageSourceCreateImageAtIndex(sourceRef, 0, imagePropertiesDictionary);if (![[sourceOptionsDict objectForKey:@"kCGImageSourceTypeIdentifierHint"] isEqualToString:@"public.tiff"]){fileURL = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/%@.%@",documentsDirectory,@"myimage",[[[sourceOptionsDict objectForKey:@"kCGImageSourceTypeIdentifierHint"] componentsSeparatedByString:@"."] objectAtIndex:1]]];CGImageDestinationRef dr = CGImageDestinationCreateWithURL ((__bridge CFURLRef)fileURL,(__bridge CFStringRef)[sourceOptionsDict objectForKey:@"kCGImageSourceTypeIdentifierHint"],1,NULL);CGImageDestinationAddImage(dr, imageRef, imagePropertiesDictionary);CGImageDestinationFinalize(dr);CFRelease(dr);}else{NSLog(@"no valid kCGImageSourceTypeIdentifierHint found …");}// clean up
                 CFRelease(imageRef);CFRelease(imagePropertiesDictionary);CFRelease(sourceRef);}else {NSLog(@"image_representation buffer length == 0");}}failureBlock:^(NSError *error) {NSLog(@"couldn't get asset: %@", error);}];