A robust and fast travel speed inference system based on SURF keypoint matching
The SURF keypoint algorithm is extremely robust, however it is essential that the accuracy of logging the time of capture for each image is to within the microsecond.
For example, at speeds of 10 km/h and a 0.03 s/frame capture rate, the distance between two points in two consecutive images is 0.0877 meters. If the estimation of the time differential is off by 0.01 seconds, this causes the predicted velocity to change from 10.0 km/h to 7.893 km/h.