Marker method is a video signal processing algorithm for counting a passing object. The method has a weakness when applying on one lane. Double counting appears due to imperfect binary frame. In this paper, we adopt the method on three lanes to count a passing vehicle. This is to explore if the method has other weakness or not. So the result can be considered to expand the method or model a better algorithm. In the testing, a video sample is taken from 68 passing vehicles on the toll road. The performance on three lanes is on 91.18% accuracy. Beside the imperfect binary frame, another error occurs because a vehicle moves to other lane. This causes a double counting too. So, to get the best result, the method is recommended for counting a passing object on one lane if we use a good algorithm on generating the binary frame. Also, we should select on a road that has barriers between their lanes if we apply the method on many lanes.

Marker method, count a passing vehicle, three lanes.