StackOverflow2013

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copied!<p>There are several answers above and elsewhere on SO that give most of what you want. Here is the working code I generated from all of these sources, and it seems to work just fine.</p> <p>This is all done within the captureStillImageAsynchronouslyFromConnection block. My thanks to all the various contributors:</p> <pre><code> [stillCapture captureStillImageAsynchronouslyFromConnection: stillConnection completionHandler: ^(CMSampleBufferRef imageSampleBuffer, NSError *error) { if (error) { NSLog(@"snap capture error %@", [error localizedDescription]); return; } NSData *jpegData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageSampleBuffer]; CFDictionaryRef attachments = CMCopyDictionaryOfAttachments(kCFAllocatorDefault, imageSampleBuffer, kCMAttachmentMode_ShouldPropagate); CFMutableDictionaryRef mutableAttachments = CFDictionaryCreateMutableCopy(NULL, 0, attachments); // Create GPS Dictionary NSMutableDictionary *gps = [NSMutableDictionary dictionary]; CLLocation *location = <your location source here>; // GPS tag version [gps setObject:@"2.2.0.0" forKey:(NSString *)kCGImagePropertyGPSVersion]; // Time and date must be provided as strings, not as an NSDate object NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; [formatter setDateFormat:@"HH:mm:ss.SSSSSS"]; [formatter setTimeZone:[NSTimeZone timeZoneWithAbbreviation:@"UTC"]]; [gps setObject:[formatter stringFromDate:location.timestamp] forKey:(NSString *)kCGImagePropertyGPSTimeStamp]; // Latitude [gps setObject: (location.coordinate.latitude < 0) ? @"S" : @"N" forKey:(NSString *)kCGImagePropertyGPSLatitudeRef]; [gps setObject:[NSNumber numberWithDouble:fabs(location.coordinate.latitude)] forKey:(NSString *)kCGImagePropertyGPSLatitude]; // Longitude [gps setObject: (location.coordinate.longitude < 0) ? @"W" : @"E" forKey:(NSString *)kCGImagePropertyGPSLongitudeRef]; [gps setObject:[NSNumber numberWithDouble:fabs(location.coordinate.longitude)] forKey:(NSString *)kCGImagePropertyGPSLongitude]; // Altitude if (!isnan(location.altitude)){ // NB: many get this wrong, it is an int, not a string: [gps setObject:[NSNumber numberWithInt: location.altitude >= 0 ? 0 : 1] forKey:(NSString *)kCGImagePropertyGPSAltitudeRef]; [gps setObject:[NSNumber numberWithDouble:fabs(location.altitude)] forKey:(NSString *)kCGImagePropertyGPSAltitude]; } // Speed, must be converted from m/s to km/h if (location.speed >= 0){ [gps setObject:@"K" forKey:(NSString *)kCGImagePropertyGPSSpeedRef]; [gps setObject:[NSNumber numberWithDouble:location.speed*3.6] forKey:(NSString *)kCGImagePropertyGPSSpeed]; } // Heading if (location.course >= 0){ [gps setObject:@"T" forKey:(NSString *)kCGImagePropertyGPSTrackRef]; [gps setObject:[NSNumber numberWithDouble:location.course] forKey:(NSString *)kCGImagePropertyGPSTrack]; } CFDictionarySetValue(mutableAttachments, kCGImagePropertyGPSDictionary, CFBridgingRetain(gps)); // NSDictionary *ma = (__bridge NSDictionary *)(mutableAttachments); // NSLog(@"photo attachments: %@", ma); [ROOTVC.library writeImageDataToSavedPhotosAlbum:jpegData metadata:(__bridge id)mutableAttachments completionBlock:^(NSURL *assetURL, NSError *error) { if (error) { NSLog(@"XXX save to assets failed: %@", [error localizedDescription]); } else { [self processAsset:assetURL inGroup:ROOTVC.venue forMessage:savingMessage]; } }]; if (mutableAttachments) CFRelease(mutableAttachments); if (attachments) CFRelease(attachments); }]; </code></pre> <p>As always, I worry if I am getting the releases right. Here's a jhead(1) of the result:</p> <pre><code>File name : 20131001_082119/photo.jpeg File size : 82876 bytes File date : 2013:10:01 08:21:19 Resolution : 480 x 360 Orientation : rotate 90 Flash used : No Focal length : 4.1mm (35mm equivalent: 30mm) Exposure time: 0.0083 s (1/120) Aperture : f/2.2 ISO equiv. : 6400 Whitebalance : Auto Metering Mode: pattern Exposure : program (auto) GPS Latitude : N 40d 43m 22.32s GPS Longitude: W 74d 34m 39.15s GPS Altitude : 117.92m </code></pre>

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