GPS and Geotagging

 

GPS and Geotagging Overview

JetPhoto Studio enables users to review and browse photos with an enclosed map on which to show the locations where photos were taken. Every photo or video managed by JetPhoto can have a latitude-longitude coordinate value to specify the locations.

As the convention in JetPhoto, latitude-longitude points are expressed in the WGS84 (World Geodetic System 1984) coordinate system that is employed by GPS (Global Positioning System). Google Maps, Google Earth or other commom LBS also adopts WGS84 datum.

The latitude need to be a number between -90 and 90 degrees (a negative number is for South, and a positive number is for North). The longitude need to be a number between -180 and 180 degrees (a negative number is for West, and a positive number is for East). The elevation is an altitude number in meters (a negative number is for below sea level, and a positive number is for above sea level). JetPhoto Studio users can directly view and edit the latitude, longitude and elevation values for a photo or video in its information list.

The procedure to locate photos is commonly known as 'Geotagging'. Presently, with JetPhoto Studio, we have three geotagging methods to locate your photos:

1. Use a GPS-enabled camera to take photos.
2. Use a common camera and a GPS logger (or a GPS device with the data logging feature).
3. Use the software to point photos on maps to set the locations manually.

 

GPS-enabled Camera
The GPS-enabled camera is not a fresh concept yet. Some professional photographers are used to using Nikon DSLRs with a mounted GPS unit, and more models of consumer digital cameras with built-in GPS can be chosen. With a GPS-enabled camera, the geodata (location information) can be recorded and saved in the photo files directly by the camera when taking shots. And JetPhoto Studio will read the saved geodata from the photo files after transferring photos from the camera.

Besides the GPS sensor, GPS-enabled cameras are usually assembled with a digital compass sensor too. With the compass, the camera can detect and record the lens heading for your photo shooting. JetPhoto Studio will also read the camera attitude from the photo files.

Nikon DSLR + mounted GPS Camera with built-in GPS iPhone*

* The camera app works on iPhone can save geodata into the captured photo or video files that JetPhoto Studio 100% supports.

 

Common Camera + GPS Logger
Besides directly using GPS-enabled cameras to take photos with geodata, you can also try another easy and universal solution to locate photos taken by any common camera if you have a GPS logger that needn't a hard connection to the camera. JetPhoto employs an efficient method to match digital photos with time synchronized GPS track logs. The particular location of a longitude-latitude coordinate will be set for each photo automatically.

To obtain the benefit of automatic photo locating, a GPS logger or a GPS device with data logging feature is required, and need turn on its power to record GPS tracks when taking your photos with the camera. JetPhoto supports Garmin, Magellan GPS handholds, many models of GPS loggers and watches, also allows importing track logs from GPX, NMEA and OziExplorer files that can be recorded by more unlisted compatible GPS devices or mobile apps working on GPS-enabled phones.

GPS handhold GPS phone GPS logger GPS watch

 

After geotagging, JetPhoto Studio can link all located photos on Google Earth and Google Map Gallery as well as more websites with geodata support, such as Flickr and Panoramio.

 

 

Quick Start with GPS

Here let's focus on the second solution mentioned above to geotag photos using a common camera and a GPS logger.

Assumes you have had a GPS logger that recorded the tracks when you was taking photos. Now you returned home, and imported all photos into an album in your JetPhoto Studio. After that, let's finish photo locating within three steps.

STEP 1
Connect your GPS device to the USB port on your Mac. ( If the GPS model need a connection to a serial port on the computer, an USB-serial adaptor may be required. And, if the GPS model need a bluetooth wireless connection to the computer, first you should also pair the GPS device with your Mac. )

Select 'Map' tab in album main window or 'Geotag' tab in extra side panel, click button 'Locate Photos with GPS'. And then show 'GPS Logs' window, in which click button 'GPS Importing' and select item 'Download from GPS logger' in the pull-down menu to retrieve your GPS tracks.

If your GPS logger can be mounted as a USB disk that stores log files, please select item 'Import from GPS files' in the pull-down menu to retrieve your GPS tracks.

If the GPS model is unable to work with JetPhoto Studio directly, also can use vendor's software bundled with your GPS device to download track logs into files in GPX, NMEA or OziExplorer format. After that, import these track log files into JetPhoto Studio.

STEP 2
Click button 'Automatic Locating', and select item 'Match all photos with GPS tracks' in the pull-down menu. JetPhoto Studio will run the processing to match photos with time-synchronized GPS tracks, this may take up to a few minutes. After the processing to calculate photo locations, the geodata will be assigned to the photos managed in the album.



STEP 3
In Map view page, now you can browse photos by location. And the geodata of photos (latitude, longitude and elevation) are listed in 'Information' extra panel.
A wikipedia box in 'Geotag' extra panel will give you more information about the places near your photos, that's done with reverse geocoding automatically.

- Click button in Map view page to launch Google Earth on which links all located photos (and related tracks).
- Click button in Map view page to make a dynamic web gallery to link located photos (and related tracks) on Google Map.

 

 

Locating Photos with Tracks

Track is the GPS log contains a series of sequential location-time pairs. The GPS logger commonly fixes and records positions with a given frequency, for example, recording a track point every 3 seconds. The record of each track point contains a latitude-longitude coordinate and a timestamp. And, the track is many track points connected in a sequence.

 

Import tracks
Select 'Map' tab in album main window or 'Geotag' tab in extra side panel, click button 'Locate photos with GPS' to show a 'GPS Logs' window. Click button 'GPS Importing', and select item 'Download from GPS logger' in the pull-down menu to show a dialog box, in which please choose GPS device type, connection port and select option 'Download Tracks'. Click button 'Import' to download all track logs from the connected GPS device.

Besides directly download tracks from GPS devices, you can click button 'GPS Importing' to get more importing options. JetPhoto Studio enables users to import GPS tracks from GPX, NMEA, OziExplorer, SONY GPS-CS1/CS3 log and Magellan SD files.

 

List tracks
All downloaded track logs are listed in 'GPS Logs' window. To correctly display time value in the track list, please select the time zone as where the track was logged.
Click the pencil icon button to change the name of current selected track log. Click the ( - ) icon button to delete current selected track log from the list.

Time zone of the tracks is a very important setting here, it must be same as the time zone of your digital photo capture time. The automatic locating is a processing to match photos with time-synchronized GPS tracks, so you must keep camera time and GPS time in a same time zone.

 

Match photos with tracks
Click button 'Automatic Locating' in 'GPS Logs' window, and select item 'Match all photos with GPS tracks' in the pull-down menu. JetPhoto Studio will add geographical location properties (latitude, longitude, elevation) for the photos that were tracked with GPS. JetPhoto Studio finds the track point with appropriate logging time that matches the photo capture time. The found track points will be displayed in the map view, in this case, one point corresponds to one photo.

Each one of the matched photos will have Longitude and Latitude properties. You can know them in photo information list with selecting Information extra panel, or review the photo location on a map with selecting Geotag extra panel.

When you only want to geotag the specified photos with GPS tracks, you can select photos in the album window as you need, and choose item 'Match selected photos with GPS tracks' in the pull-down menu here.

The accuracy of the photo locating depends on a parameter that can be decided by user. While matching photos with time-synchronized GPS tracks, the program only locates the photo if time difference to the nearest track point is less than a given shorter time. The default time range is less than 300 seconds, and you can click button 'Automatic Locating' in 'GPS Logs' window and select item 'Parameters' in the pull-down menu to change the parameter.

 

Time Calibration
Sometimes the photographer uses GPS logger, but forgot to keep the time setting on the camera accurately. Due to the difference between the camera time and the GPS time, photo locating results have to be inaccurate with a time-synchronized matching.

For the accurate matching, JetPhoto Studio already provides two methods to calibrate photo capture time. You could find two menu items in Calendar extra panel, click the gear button to choose Adjust time zone or Correct capture time.

Here show a demonstration to explain how to calibrate photo capture time accurately:
As our experience, in order to know the time offset between your GPS and your camera, what you should do is to take a picture for the GPS receiver monitor or any clock displaying a standard time*.

* GPS time is equal to the accurate standard time. GPS receiver gets the time from GPS satellites.

As above sample picture, we know the photo capture time in the camera is 2006-08-29 10:15:02, but the photo capture time in the GPS is 2006-08-29 10:15:25. Therefore, the time offset between two devices is 23 seconds. The user need to plus 23 seconds for each photo's capture time before run the processing to match photos with GPS tracks.

Then, just need select all photos in the album window, and use the tool to correct the capture time for photos in a batch.
know more >

NOTE: GPS time is always equal to the accurate standard time that you can find on your Mac also. If your GPS unit doesn't have a monitor to display the time, please just take a picture for this clock interface instead.



(Mac OS X can set date & time automatically synchronized with Internet time server to ensure the time displayed is accurate.)

 

 

Locating Photos with Waypoints

Users can mark waypoints with some GPS devices. The waypoint is a location record contains a latitude-longitude coordinate .

 

Import waypoints
Select 'Map' tab in album main window or 'Geotag' tab in extra side panel, click button 'Locate photos with GPS' to show a 'GPS Logs' window. Click button 'GPS Import...', choose item 'Import from GPS logger' in the pull-down menu to show a dialog box, in which please choose GPS device type, connection port and select option 'Download Waypoints'. Click button 'Import' to download all waypoints from the connected GPS device.

 

List waypoints
All downloaded waypoints are listed in 'GPS Logs' window. Click the pencil icon button to change the name of current selected waypoint. Click the ( - ) icon button to delete current selected waypoint. Click the ( + ) icon button to add a new waypoint manually (You could first select one photo that has been located to get a default latitude-longitude coordinate for the new waypoint).

 

Locate photos with waypoint
Select photos in Thumbnails view. Click button 'Manual Locating' in 'GPS Logs' window, and select item 'Locate photos with selected waypoint' in the pull-down menu. JetPhoto Studio will add geographical location properties (latitude, longitude) for the selected photos with the current selected waypoint. And then you can see the located photos corresponds to some markers on the map.

 

 

Locating Photos on Map

Even if you don't have any GPS device yet, you still can locate photos in a manual way. JetPhoto Studio enables locating photos on maps, and also supports marking camera directions as well as camera positions for your photos.

Select a photo (or several photos) in Thumbnails view, and select 'Geotag' extra panel. If the current photo is not located yet, please click button 'Locate Photos on Map', and if the current photo is already located, you can also click button 'Change Photo Location'.

Now, you can see a window with an embedded map view in which points the location where the photo was taken.

1. Search the map, enter a place name or a detailed street address to quickly locate this map to a specified place.
2. Hold mouse button and drag mouse to move the map, move the position where the photo was taken into the central target.
3. Also, if you'd like to set the camera lens heading for the photo, just click the central target to begin the direction adjusting. Click the central target again to accept the direction setting, or double click the central target to discard the direction setting.
4. Click button 'Locate Photo!', JetPhoto Studio will add Longitude, Latitude properties (and Heading property) for the photo according to the targeted location on the map.
5. Click left arrow or right arrow button to continue to locate more other photos in this album.

 

 

Other Geotagging Actions

Geotagging Assistant
Introduced the method to locate photos with GPS, maybe you have already known how to complete all steps in 'GPS Logs' window that provides an integrated interface to import and manage GPS logs, as well as use GPS logs to locate your photos. However, if you are a beginner of geotagging, another easy-to-use tool named 'Geotagging Assistant' is provided for you especially. Please choose menu item 'GPS & Geotag'->'Geotagging Assistant' or click the 'Geotagging Assistant' button in 'GPS Logs' window to start the program that offers an interface with guidance to help users to load photo files, load GPS log files, set time zone and finish the photo locating step by step.

Write GPS EXIF  
After locating photos, the geodata of photos (latitude, longitude, elevation, heading) are saved in a specific metadata file enclosed in the album package. But, JetPhoto Studio didn't write geodata inside the photo files, in other words, the location information will be lost when you use these photo files outside JetPhoto Studio. If need save the geodata into photo files permanently, you should also choose menu item 'GPS & Geotag'-> 'Write GPS EXIF Tags into Files' to write location information into the JPEG or camera RAW files stored in the album package.

 

Unset photo locations
If want to delete geodata (latitude, longitude, elevation and heading) in photo’s metadata, you can edit the info list in the extra side panel after selecting a photo, and clear all geodata fields one by one. Also a more efficient way is offered, just select one or several photo thumbnails in the album window, and select menu command “GPS & Geotag” -> “Unset Photo Locations…”. GPS location metadata will be all removed from these selected photos in the batch mode.

 

 

Navigating Photo Map

Click 'Map' tab in album main window, users can review and browse photos with a Map view in JetPhoto Studio. All photos with latitude-longitude information are indicated as a series of markers in Map view, in which three mapping modes can be selected:

- Google Map
- WMS Map *
- NASA Earth Image *

You can switch the mapping mode with selecting 'Google Map', 'WMS Map' or 'NASA Earth Image' in the mapping type popup menu at the top-left corner of the Map view. The default mapping is Google Map. When select 'NASA', the base map will use NASA Blue Marble satellite image (1 pixel every 2 kilometers) that is pre-installed with JetPhoto Studio, so no internet access is needed to show the NASA map. And select 'WMS Map', JetPhoto Studio will connect an online mapping service to retrieve the specific detailed maps using WMS . Click '...' button, users can set a WMS mapping server address.

* presently, the photo map navigating with WMS mapping and NASA Earth Image is only available in JetPhoto Studio Mac version.

 

Google Map
All located photos are linked on Google Map. Click marker to show a photo thumbnail in the balloon.
Click two arrow buttons in top-left corner of the album window, or press arrow keys (left-right or up-down keys), JetPhoto Studio will show photos with maps one by one.



Click the photo thumbnail in balloon or this button if need to show the full-size photo (and a smaller map will be shown in the extra panel).
Click this button if need to change the photo's location.
Click this button to find more geotagged resources near the current position on the internet.

 

Drag and Zoom

dzm_button.jpg Click this button in the map toolbar to allow dragging mouse to zoom the map, and also can select photos in a given rectangle area on the map.

dzm_drag.jpg

[step 1] Click the dzm_button.jpg button, then you can drag on the map to draw a rectangle with red lines to mark the area where you would like to zoom.

dzm_zoom.jpg

[step 2] JetPhoto Studio will zoom the map as long as released the mouse button after dragging.

dzm_thumbnails.jpg

[step 3] At the same time, the photos in the zoomed rectangle will be selected. Then you can select Thumbnails view in the album window, where JetPhoto Studio has spotlighted the matched photo thumbnails (unmatched photo thumbnails are greyed-out).

In this way, JetPhoto Studio provides an efficient method to quickly pick out photos that were geotagged in a given location on the map.

 

WMS Map and NASA Earth Image
If select mapping type to 'WMS Map' or 'NASA Earth Image', photo locations will be shown with some highlighted spots on the map. A small global map, a photo preview box and a toolbox are attached to the map view.

Map tools
You can select a tool button to set mouse action for the map view.

Info Pointer Click a photo spot Select a photo on the map and display its preview picture.
Drag to select a rectangle area Find photos taken in the selected area, and spotlight them in Thumbnails view.
Zoom In Click the map Zoom in the map.
Drag to select a rectangle area Zoom in the map to fit the selected area.
Zoom Out Click the map Zoom out the map.
Move Drag mouse Move the map.

 

Other options
Show Waypoints - Select checkbox 'Show Waypoints' to enable waypoints display in the map view. The waypoint is displayed as a red flag with a name label.
Show Tracks - Select checkbox 'Show Tracks' to enable tracks display in the map view. The track is displayed as a yellow curve on the map.

 

 

Google Earth and Google Maps

Besides navigating photos in Map view page in JetPhoto Studio, you can also link your photos and GPS tracks on Google Earth or Google Maps. Select 'Map' view page in the album window and see the toolbar above the map. Two buttons are there:

- Click this button to link photos to Google Earth and generate KML/KMZ files.
- Click this button to make Google Map web galleries.


Link photos to Google Earth  

Click button 'Link photos to Google Earth' to instantly launch a Google Earth application where links all located photos, or generate KMZ or KML files that can be opened with Google Earth later. With a setting dialog box, you can decide whether need show tracks and waypoints as well as photo spots on Google Earth, and customize the photo spot icon and track styles.


(A Google Earth window to show photos and tracks)

KML - KML is a XML file that can be opened with Google Earth. JetPhoto Studio exports the location information of the photos (and track data) into a specified KML, this file will be saved on disk with the referenced album package together. KML file is only an index file, it doesn't contain any photo data yet. In this case, to share this KML file, you must copy both the KML file and the referenced album package.

KMZ - KMZ is a compressed package file that can be opened with Google Earth. JetPhoto Studio exports all location information of the photos (and track data) as well as all referenced photo files in one binary package. So, to share the KMZ package, just need to copy one file. ( You can try to uncompressed the KMZ file as a common zip file, a KML file and a set of image files will be found inside. )

NOTE: If use Google Earth version 5, you must finish a necessary setting. Open the Preferences / Options in your Google Earth, select General tab, and enable option “Allow placemark balloons to access local files and personal data”. Otherwise the photos may not be shown correctly in Google Earth.

 

Make Google Map web gallery  

Click button 'Make Google Map web gallery' to make a dynamic web gallery to link located photos and show GPS tracks on Google Maps. You can publish the generated gallery files to your website.


(A Google Map Gallery)

For the details, please refer to Making Google Map Gallery in section Creating and Sharing in this document.

 

 

Address Lookup (Reverse Geocoding)

You can show your photos in maps after locating them, you can also choose menu item 'GPS & Geotag'-> 'Address Lookup (Reverse Geocoding)' to run Address Lookup program that will connect Google Maps server and invoke the reverse geocoding services to convert the latitude/longitude data to a human-readable address.

In Address Lookup dialog box, the user can select a mode to decide where to write the address. JetPhoto Studio can automatically write the addresses to Notes, Keywords or both.

For example, I took a photo in Stanford University campus. The photo has been located at latitude N37.42718º and longitude W122.17033º in JetPhoto Studio. Then, run Address Lookup program that works with the default mode, a note and three keywords will be added for the photo automatically:

- Photo Note: Stanford Memorial Church, Stanford
- Photo Keywords: Stanford, CA94305, USA