AI Assisted Ground Control Points (GCP's) Marking

AI Assisted Ground Control Points (GCP's) Marking

Machine (ML) / Artificial Intelligence (AI) can be used for marking GCP on images by looking for different shapes of marks in the images.   The search of these marks in images starts initially by using the GPS location of the images and using a complicated algorithm to decide where to search for the marks in the images.   When AI assisted GCP markup option is selected at the time the images are uploaded, the system initiates the process of looking for the marks on the images as soon as the GCP file is uploaded.   Once the search process is done, each GCP is marked potentially on several imaged several images and the process of validating accuracy is started and the result is shown. From here the process continues exactly as if the GCP's were manually marked.   Let walk through an example.

As with manual GCP marking, after the upload and the  the link process are done, the site will appear as “Pending GCP Marking” in the site map screen left banner as shown in the figure below.

The next step here would be to open the flight by clicking on the "Pending GCP Marking" right on the site tab shown above or by opening the site and then opening the flight instance. 

When the site is opened, the flight in the top banner that needs GCP marking would also appear as “Pending GCP Marking” as shown below. In this case simply open the flight by clicking on it in the top banner.

The figure below shows that the flight is in GCP Marking step and now it is possible to start the process.

Firstly, you must import the GCP file. To import a GCP's file, use one of the 3 options shown below as follows:

A:  Click on the “Import GCP” link available on the top left corner of the window, or on the "Select GCP's" button.  In both cases a file browser is opened allowing you to browse and select the desired file and open it. 
B: Open a file browser and find the desired GCP's file and simply drag it and drop it where it says "Drag and Drop GCPs here". or
C: Import GCP's from a previous flight by selecting the flight date from the available drop-down field shown.   This option appears only when there are previous flight with GCP's that are available for importing.  

 As soon as a GCP file is imported or opened, the system will give you the opportunity to confirm that you opened the correct GCP file before it starts the process of automatically marking the GCP's.  As shown in the figure below, the system shows the images and the GCP's and awaits for you to tell it to start the AI marking of GCP's.  If things look ok, the press the "Start AI Marking".

 When the the "Start AI Marking" button is pressed, the system will show the message below indicating that it is attempting to generate hints for the loaded GCP’s.

Generating the hints may take several minutes depending on the size of the flight, but when done the AI marking of GCPs starts and the window below appears. 

Once AI marking and checking accuracy are done, the results are shown and from here the GCP markings will appear green.  The green icons will need to be fine tuned to improve the accuracy.  All of the gcp markers should be adjusted so they appear orange. 

From here the process continues as with manually marking GCP's.   User here may add, delete, or adjust markings till good results are reached.  See illustration below as an example.

You may also here mark any of the GCP's as check points by checking the available CheckPoint check box next to it.  Please refer to the Using Check Points article for full details. 

As with manual marking of GCPs, when using a local coordinate system you may need to align the images with the GCPS, and also mark at least 3 GCPs, each in at least 3 images, and only after that  when the check accuracy is done, the AI marking of the rest of the GCPs starts.  Refer to the article Marking the Ground Control Points (GCP's) Manually  for details on aligning images with GCPs. 

Additionally, after the initial AI marking round or any time after Revalidating Accuray, the user will have the option to rerun the AI Marking from scratch using the "Rerun AI Marking" button shown below.

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