D-Link DCS-5020L Manual page 33

Step 6: Specify how sensiBve you would like moBon detecBon to be.
Step 7: Use your mouse to define the areas of the video that you would like to monitor for
moBon. Clicking once on a square within the grid will select that area of the video for moBon
detecBon. Clicking the same area again will deselect the area.