Geotagging

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Main Page UgCS UgCS desktop User Manual Standard operations Telemetry player

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UgCS allows tagging images taken by the drone with coordinates from recorded telemetry.

Important note, remember the difference between camera clock and clock on computer that recorded the telemetry.  


HINT: the easiest way to remember the time difference is to take a picture of computer's clock with the drone camera. Then compare time on the image with “modified” attribute of the picture. Hovering the mouse over the clock placed in top right corner of UgCS will provide a hint with current time detailed up to milliseconds.

Geotagging tool is available from context menu of vehicle in telemetry player (Telemetry player workspace).

After pressing “Geotagging” the following window appears (Geotagging window).

Geotagging window



Click “Browse” to select images. Only JPEG is supported for now.

Number of images will be shown, time from the first and last image as start and end time.

The process of geotagging is straightforward. Choose image and try to find the closest telemetry record in the database. For search to be as precise as possible it is important to know camera time offset – the difference between camera clock and computer (where telemetry was initially recorded) clock

If data was processed on a computer with clock configured for another UTC time zone, than the camera time zone, checkbox “Set camera UTC time zone if it’s different from PC UTC time zone” needs to be set and camera's UTC time zone specified.

After everything is configured, press 'Process'. Algorithm will try to find coordinates for the pictures. After processing is complete, the button 'Show on map' will display camera position for each picture taken.

If everything is correct, select altitude type from dropdown list - AMSL, AGL, RAW or None and press “Write tags to image files” to save coordinates and selected altitude as EXIF tags into pictures.

How to prepare photo for geotagging processing

1. In order to synchronize time between the capturing device and UgCS desktop, take several pictures of UgCS desktop screen with open time toolbar.

a. In UgCS navigate the mouse cursor over the time widget, located in the top right corner.
b. The Time toolbar will appear.
c. Make a picture of the computer screen with the camera.

Time tooltip



2. Connect the vehicle to the PC/notebook to import telemetry data from the drone.

3. Execute mission in automatic or manual mode with camera working in periodic photo mode.

How to write geotags to photo files

1. Copy photo files from camera and back it up.
2. Open telemetry player. Add drone to the vehicle list. Check that telemetry data can be found for selected drone.
3. Open geotagging window for selected drone.
4. Calculate time offset value. For this calculation, compare camera time and photo time.
a. Take photo of UgCS desktop time by camera and select time from picture - this is photo time;
b. Open UgCS client -> telemetry player -> add vehicle -> open geotagging window;
c. Click Browse and select photo from previous step;
d. Camera time is displayed in geotagging window at string after words “start time”;
e. Calculate difference between two values in seconds.
5. Add all photos from camera (exclude photo with screen).
6. Set calculated camera offset. Set time zone of the camera if necessary.
7. Process and save geotags to photo files.