Create a Reality mapping workspace for drone imagery

Available with Standard or Advanced license.

Available for an ArcGIS organization with the ArcGIS Reality license.

The data requirements and workflow below explain how to set up a Reality mapping workspace using drone imagery.

Data requirements

The workflow for processing drone imagery requires two types of data:

• Geolocation and camera model—This information is commonly stored as metadata in the image files, typically in the EXIF header, and includes latitude, longitude, altitude, and camera type. The camera type is used to compute a camera model based on the specifications of the camera.
• Elevation source—This information provides an initial height reference for computing the block adjustment. This height reference can be derived from a digital elevation model (DEM) or the image metadata, or you can specify an average elevation or z-value.

Create a Reality mapping workspace

To create a Reality mapping workspace using drone imagery, complete the following steps:

1. On the Imagery tab, click New Workspace.
2. On the Workspace Configuration page, type a name for the workspace.
3. Ensure that the Workspace Type option is set to Reality Mapping.
4. From the Sensor Data Type drop-down list, choose Drone.
5. From the Basemap drop-down list, choose a basemap as a backdrop for the image collection.

   You can also import and use an existing image collection for your workspace.

6. Optionally, check the Allow adjustment reset check box if you want to revert your workspace to a previous state.
7. Click Next.

   

8. On the Image Collection page, ensure Generic is chosen as the Sensor Type option.

   Only the generic drone sensor type is supported, which is a single-sensor drone system with numerous camera models. Multispectral drone data is not supported.

9. Click the Add button, browse to a folder, and load the imagery for the project. If the images are in subfolders, click the Add images drop-down menu and select the Include sub folders option.
   
   The Geolocation and Cameras parameters are automatically populated from the metadata in the EXIF headers.

   If the images in the collection do not contain an EXIF header, provide a GPS text file for Geolocation, such as a comma-separated values file (.csv) that includes values for the Image Name, Latitude, Longitude, and Altitude fields, and optionally, the Omega, Phi, and Kappa fields. Use the geolocation file provided by your vendor with the drone imagery.

   Note:

   To support accurate block adjustment, ensure the camera model parameters, such as focal length are accurately defined. Within the Image Collection window, the camera model properties can be edited to align the camera parameters with the manufacturer’s specifications.

10. Click the Import button to browse to the GPS text file.
Z-values are typically recorded as height above a vertical datum or height relative to the takeoff point.
11. To edit the altitude reference of the image collection, click the Edit button next to the geolocation information.
    1. For Z Value Type, choose Flight Height if the drone reports height relative to the takeoff point, or Altitude for height relative to a vertical datum.
    2. Click OK to save the settings on the Edit Geolocation Reference page.

    Spatial Reference is automatically populated with the GPS location from the data.

12. Optionally, click spatial reference and choose a different map reference system and vertical coordinate system.

    The coordinate systems of the workspace are used in the map, resulting orthomosaic, and DEM.

13. If the camera type is missing from the EXIF header information, click the Properties button to open the Edit Camera Parameters page and select the appropriate Camera Maker and Camera Model values.

    

    Once you select the camera make and model, the wizard automatically populates the form based on the database of supported cameras and computes the camera model, also known as the interior orientation. If your camera is not supported, you can provide the camera information on the Edit Camera Parameters page and save it. The camera parameters settings will be used to compute the camera model.

    Note:

    Only Focal length and Pixel Size on the Sensor values are required to compute the camera model. These values may be available in the image properties. If the values are not available, the Pixel Size on the Sensor value is automatically calculated for the 35 mm equivalent focal length for supported camera models using the equations below:

    Pixel Size = CCD Diagonal / Image Diagonal(in pixels)

    where

    CCD Diagonal = 2 * (Focal Length * Tan(FOV/2))

14. If the Pixel Size on the Sensor value is not calculated automatically, click the Pixel Size on the Sensor button ; choose Field of view (FOV), 35 mm equivalent focal length, or Dimension from the Sensor Specification drop-down menu; provide the corresponding specifications for your camera model; and click OK.
    1. Choose the correct Camera File value with the camera model information.

       This can be a .cam file or a .csv file. If neither is available, manually enter the camera parameters on this page.

    2. Click the Back button to return to the Image Collection page.

    Pixel Size on the Sensor is now populated.

15. On the Data Loader Options tab, choose an Elevation Source option.

    • If you have access to the internet, use Average Elevation from DEM for the Elevation Source parameter and the default elevation service for the DEM parameter.
    • If you do not have access to the internet, provide a DEM file covering the project area, and choose Average Elevation for the Elevation Source parameter.
    • If you do not have access to the internet or a DEM, choose the Constant Elevation option from the drop-down menu and provide an elevation value. This is only used as an initial estimate of the flight height for each image.

16. Optionally, in the Advanced Options section, edit the Band Combination parameters to reorder the band combination from the default order.

    

17. Click Finish to create the workspace.

When the Reality mapping workspace is created, the image collection is loaded in the workspace and displayed on the map. You can now perform block adjustments and generate Reality mapping products.