To output speed data in Counter Mode the distance from the camera to the flow of each direction of traffic must be measured. By measuring the distance to each direction of traffic flow Counter Mode is able to more accurately output speeds on different two-lane, bi-directional roadway cross sections, including:

• Raised medians
• Painted medians
• Wide traffic lanes
• Narrow traffic lanes

To provide an accurate measurement the distance from the camera face to the nearest side of each flow of vehicle traffic should be determined. This nearest side of vehicle traffic should align with, if not be equal to the wheel path of each direction of traffic flow.

The image at the start of this article provides an example for the measurement of rightbound and leftbound traffic.