Title :
Estimating Velocity Fields on a Freeway From Low-Resolution Videos
Author :
Cho, Young ; Rice, John
Author_Institution :
Dept. of Stat., California Univ., Berkeley, CA
Abstract :
An algorithm to estimate velocity fields from low-resolution video recordings is presented. The algorithm does not attempt to identify and track individual vehicles, nor does it attempt to estimate derivatives of the field of pixel intensities. Rather, a frame is compressed by obtaining an intensity profile in each lane along the direction of traffic flow. The speed estimate is then computed by searching for a best matching profile in a frame at earlier and later times. It is shown that the estimate is equivalent to a weighted median of velocities of vehicles. Because the algorithm does not need high-quality images, it is directly applicable to a compressed format digital video stream, such as .mpeg, from conventional traffic video cameras. The procedure is illustrated using a 15-min-long Video Home System recording to obtain speed estimates on a 1-mi stretch of highway I-80 in Berkeley, CA
Keywords :
road traffic; traffic information systems; velocity measurement; video recording; video signal processing; freeway; low resolution video recording; speed estimate; traffic flow; velocity field estimation; Cameras; Detectors; Image motion analysis; Monitoring; Road transportation; Spatial resolution; Traffic control; Vehicle detection; Velocity measurement; Video recording; Traffic information systems; velocity measurement; video cameras;
Journal_Title :
Intelligent Transportation Systems, IEEE Transactions on
DOI :
10.1109/TITS.2006.883934