Abstract Several algorithms have already made to estimate vehicle’s speed using single camera. The main problem is the efficiency of these systems: processing is done on the whole image while moving objects occupy only a specific part. This work aims to present a technique of speed estimation based on one pixel’s width line processing. This line image can be extracted from a full size image or from a line camera in order to apply some processing like background subtraction, morphological operations, binarization and finally blob detection to allow tracking. This new approach enables implementation on low-cost platforms with low computing power. The size of data to process can almost be divided by the width’s image of a standard resolution camera, allowing a low data rate from acquisition.