I am trying to save GPS data along with EXIF data for a photo taken in iphone. I went through below SO question and was able to tag GPS data with a photo.
LINK: SOURCE
When i click on selectPhoto button, the photo is duplicating inside cameraroll. Below is my complete code.
- (IBAction)takePhoto:(id)sender {
UIImagePickerController *picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.allowsEditing = YES;
picker.sourceType = UIImagePickerControllerSourceTypeCamera;
[self presentViewController:picker animated:YES completion:NULL];
}
- (IBAction)selectPhoto:(id)sender {
UIImagePickerController *picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.allowsEditing = YES;
picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
[self presentViewController:picker animated:YES completion:NULL];
}
#pragma mark - Image Picker Controller delegate methods
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
UIImage *image = [info objectForKey:@"UIImagePickerControllerOriginalImage"];
self.imageView.image = image;
NSLog(@"image %@\ninfo: %@",image, info);
[picker dismissViewControllerAnimated:YES completion:NULL];
[self saveImage:image withInfo:info];
}
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker {
[picker dismissViewControllerAnimated:YES completion:NULL];
}
- (void) saveImage:(UIImage *)imageToSave withInfo:(NSDictionary *)info
{
// Get the image metadata (EXIF & TIFF)
NSMutableDictionary * imageMetadata = [[info objectForKey:UIImagePickerControllerMediaMetadata] mutableCopy];
// add (fake) GPS data
double latitude = locationManager.location.coordinate.latitude;
double longitude = locationManager.location.coordinate.longitude;
CLLocationCoordinate2D coordSF = CLLocationCoordinate2DMake(latitude ,longitude);
// arbitrary altitude and accuracy
double altitudeSF = 0.0;
double accuracyHorizontal = 0.0;
double accuracyVertical = 0.0;
NSDate * nowDate = [NSDate date];
// create CLLocation for image
CLLocation * loc = [[CLLocation alloc] initWithCoordinate:coordSF altitude:altitudeSF horizontalAccuracy:accuracyHorizontal verticalAccuracy:accuracyVertical timestamp:nowDate];
// this is in case we try to acquire actual location instead of faking it with the code right above
if ( loc ) {
[imageMetadata setObject:[self gpsDictionaryForLocation:loc] forKey:(NSString*)kCGImagePropertyGPSDictionary];
}
// Get the assets library
ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
// create a completion block for when we process the image
ALAssetsLibraryWriteImageCompletionBlock imageWriteCompletionBlock =
^(NSURL *newURL, NSError *error) {
if (error) {
NSLog( @"Error writing image with metadata to Photo Library: %@", error );
} else {
NSLog( @"Wrote image %@ with metadata %@ to Photo Library",newURL,imageMetadata);
// NSLog( @"Wrote image with metadata to Photo Library");
}
};
// Save the new image to the Camera Roll, using the completion block defined just above
[library writeImageToSavedPhotosAlbum:[imageToSave CGImage]
metadata:imageMetadata
completionBlock:imageWriteCompletionBlock];
}
/**
A convenience method to generate the {GPS} portion of a photo's EXIF data from a CLLLocation.
@param location the location to base the NSDictionary on
@return NSDictionary containing {GPS} block for a photo's EXIF data
*/
- (NSDictionary *) gpsDictionaryForLocation:(CLLocation *)location
{
CLLocationDegrees exifLatitude = location.coordinate.latitude;
CLLocationDegrees exifLongitude = location.coordinate.longitude;
NSString * latRef;
NSString * longRef;
if (exifLatitude < 0.0) {
exifLatitude = exifLatitude * -1.0f;
latRef = @"S";
} else {
latRef = @"N";
}
if (exifLongitude < 0.0) {
exifLongitude = exifLongitude * -1.0f;
longRef = @"W";
} else {
longRef = @"E";
}
NSMutableDictionary *locDict = [[NSMutableDictionary alloc] init];
// requires ImageIO
[locDict setObject:location.timestamp forKey:(NSString*)kCGImagePropertyGPSTimeStamp];
[locDict setObject:latRef forKey:(NSString*)kCGImagePropertyGPSLatitudeRef];
[locDict setObject:[NSNumber numberWithFloat:exifLatitude] forKey:(NSString *)kCGImagePropertyGPSLatitude];
[locDict setObject:longRef forKey:(NSString*)kCGImagePropertyGPSLongitudeRef];
[locDict setObject:[NSNumber numberWithFloat:exifLongitude] forKey:(NSString *)kCGImagePropertyGPSLongitude];
[locDict setObject:[NSNumber numberWithFloat:location.horizontalAccuracy] forKey:(NSString*)kCGImagePropertyGPSDOP];
[locDict setObject:[NSNumber numberWithFloat:location.altitude] forKey:(NSString*)kCGImagePropertyGPSAltitude];
NSLog(@" locDict %@", locDict);
return locDict;
}
