Define a water body mask

Available with Advanced license.

Water bodies can be difficult to process cleanly because of turbulence and strong reflections. These factors often alter pixel values significantly between images and prevent accurate reconstruction. With the Waterbody Mask tool, you can draw or import a water body layer to mask these problematic areas so they can be interpolated into an accurate result. During product generation, water body polygons are applied to the raw data on the fly, so any intermediate data remains unaltered by this process.

Note:

The water body mask that is drawn or imported into the project should be at least partly within the boundary of the flight area and image collection. Otherwise, a processing error may occur.

Create a water body mask

To create a water body mask, complete the following steps:

1. On the Home tab, click the Waterbody Mask button in the Pre-Processing group.
2. From the drop-down list, click the Create Waterbody option.

   The Create Features pane appears.

3. Use the editing tools to draw a new polygon to define the water body area.
4. Close the Create Features pane.

Import a water body mask

To import a water body mask, complete the following steps:

1. On the Home tab, click the Waterbody Mask button in the Pre-Processing group.
2. From the drop-down list, click the Import Waterbody option.

   The Browse to Feature Class dialog box appears.

3. Browse to and select the feature layer or shapefile that will be used for the water body, and click OK.

Remove a water body mask

To remove a water body mask, complete the following steps:

1. On the Home tab, click the Waterbody Mask button in the Pre-Processing group.
2. From the drop-down menu, click the Clear Waterbody option.

   The water body mask layer in the table of contents is cleared of all polygons.

Use water body features with tile-based processing

You can use water body features in combination with tile-based processing to fix areas of poor water reconstruction. There are two methods to apply the tile-based processing workflow. The first method allows you to reprocess tiles but maintains the original tile in a mosaic dataset. This means you can select which tile you want to keep on a tile-by-tile basis. The second method automatically overwrites the tiles that have water body features and writes a full new True Ortho. The original True Ortho is maintained in the project folder as a backup. To learn more about reprocessing, see reprocessing.

Note:

Since tile-based processing is only intended for True Ortho products, it is advisable to turn off all other products when attempting the following workflows to save time. Otherwise, any enabled product will be regenerated and prolong processing times.

Individual tile processing

You can configure True Orthos to be created without the merge tiles option. This generates a mosaic dataset with all imagery separated into tiles. These tiles can have water body features drawn over them and reprocessed.

Choose which tiles to use with individual tile-based processing.

1. From the Home tab, click the Options button in the Processing group to open the Options window.
2. Browse to the 2D products tab.
3. Uncheck the Merge Tiles check box in the True Ortho section.
4. Click Apply and click OK.
5. Click the Start button on the Home tab to begin processing.

   Ensure that the True Ortho product is checked before processing.

6. Once processing completes, click the Waterbody Mask drop-down menu on the Home tab.
7. Choose the Create Waterbody option.

   The Create Features pane appears and automatically starts an edit session with the polygon template enabled for drawing.

8. Draw a new feature over any areas that require modification.
9. Click the Finish button on the editing toolbar in the map window.
10. Close the Create Features pane.
11. Press Start to begin reprocessing the tiles with your drawn features.

    Once processing completes, review the result. You may need to uncheck the preprocessing layers to see the changes.

12. Confirm that the new tile has been created.

    By default, the First mosaic operator is used to display the tiles in the mosaic dataset. Any new tiles will appear as the first raster dataset and be pushed to the top of the display order. Subsequent runs of the workflow will create additional tiles and continue to use the same operator. To change the mosaic dataset operator for the True Ortho, click the True Ortho tiles layer in the Contents pane. The Mosaic Layer tab appears on the ribbon and contains the Image Display Order group for modifying mosaic dataset display.

Mass tile processing

When you use the default option of merging tiles for generating a True Ortho, tiles are not individually selectable. Instead, you can draw the water body features over the existing True Ortho, and Drone2Map automatically reprocesses those tiles. The end result is a new True Ortho with your preprocessing features applied. Each new processing run will store the old True Ortho in a new backup folder in the project folder. To learn more about reprocessing, see Data reprocessing.

Draw features and iteratively process True Orthos to make tile-based water body corrections.

1. Check the True Ortho product in the Manage pane.
2. Click the Start button on the Home tab to begin processing.
3. Once processing completes, click the Waterbody Mask drop-down menu on the Home tab.
4. Choose the Create Waterbody option.

   The Create Features pane appears and automatically starts an edit session with the polygon template enabled for drawing.

5. Draw a new feature over any areas that require modification.
6. Click the Finish button on the editing toolbar in the map window.
7. Close the Create Features pane.
8. Press Start to begin reprocessing the tiles with your drawn features.

   Once processing completes, review the result. You may need to uncheck the preprocessing layers to see the changes. A backup of the original True Ortho is created and stored in the project folder under \Products\2D\True Ortho\backup. Subsequent runs of the workflow will continue to produce backup folders with the previously processed True Ortho in them.