How to select specific input data for A.I. Inference

Editor → Current Situation (Ribbon tab) → Overlays (Ribbon bar)

It is possible to mask the image layer of a satellite input in a Combo Overlay. This way you can specifically in- or exclude certain areas from the Inference Overlay. Below you will find two examples, which require that you already have a regular inference overlay set up.

Exclude open water areas from an Inference Overlay

Sometimes foliage inference will also place foliage incorrectly on open water. In case you would like to exclude areas such as open water, or already existing BGT trees, you can use the following steps.

How to exclude open water from an Inference Overlay:

1. Add an Average Overlay, we will use this to assign water areas.
2. With this overlay selected, set the input options to "Attribute: Specific Layer" and "Terrains".
3. Because we want a sharp distinction between water and land, we set the cell averaging distance to 0 meters.
4. As attribute to look for, we select "WATER".
5. Select finally "Update Now", and you have created an overlay that displays all open water areas.
6. Now add a Combo Overlay.
7. Select the Original Satellite overlay as input for Grid A.
8. Select the Avg Water Terrains overlay as input for Grid B.
9. Enter the following formula: "IF(GT(B, 0), NO_DATA, A)". This formula checks wether a point is in a water area. If so, it returns no data, else it returns the satelite image.
10. Select again "Update Now".
11. Now use this new combo overlay with a fitered satelite image as input for your inference overlay, and update. You have now excluded open water areas from your inference overlay.

• 
  AVG Water Areas overlay settings
• 
  AVG Water Areas overlay
• 
  Combination layer settings, for filtering out open water from satellite layer.
• 
  Using Combination layer as input for Inference Overlay

Only include private yards, and exclude the rest from an Inference Overlay

To improve a heat stress calculation, using inference to gain data of foliage in private gardens can be very helpful. For this you can mask all data except private yards from the satelite image.

How to only include private yards, and exclude the rest from an Inference Overlay:

1. Add an Average Overlay, we will use this to assign private yards.
2. With this overlay selected, set the input options to "Attribute: Specific Layer" and "Buildings".
3. Because we want a margin all around to look for foliage at the edges of the private Yards, we set the cell averaging distance to 3,5 meters.
4. As attribute to look for, we select "PRIVATE_YARD".
5. Select finally "Update Now", and you have created an overlay that displays all private yard areas/ gardens.
6. Now add a Combo Overlay.
7. Select the Original Satellite overlay as input for Grid A.
8. Select the Avg Private Yards overlay as input for Grid B.
9. Enter the following formula: "IF(GT(B, 0), A, NO_DATA)". This formula checks wether a point is in a private yard. If so, it returns the satellite image, else it returns no data.
10. Select again "Update Now".
11. Now use this new combo overlay with a filtered satelite image as input for your inference overlay, and update. You have now excluded everything but private yards from your inference overlay.

• 
  AVG Private Yards overlay settings.
• 
  AVG Private Yards overlay.
• 
  Combination layer settings, for excluding everything except private yards.
• 
  Inference overlay excluding everything but private yards.

Notes

• The detected foliage overlay can be used to import as trees or foliage areas into your project.
• The Combo Overlay only accepts a satellite image as input in Grid A.
• You can combine multiple masking overlays; for example you can look for only private yards, but exclude already existing BGT trees.

How-to's

• How to import trees based on an Inference Overlay
• How to create foliage height areas based on an Inference Overlay
• How to detect foliage using an Inference Overlay