Measuring distance of camera from line running parallel to the camera motion?

I have a case where my camera is trying to move at a certain velocity in a fixed direction. All the time, it is moving parallel to a line (the edge of some table, for instance).

It sees the line as follows:

For a better visualisation, image the edge/line terminating towards the center of the frame while the camera tries to approach the center.

Is it possible for the camera to know its distance from this line ?