High-ratio bandwidth reduction of video imagery for remote driving
Dale R. Shires, Franklin F. Holly, Phillip G. Harnden · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1992
In an effort to remove the soldier, to the extent possible, from harm's way, some of the Army's future combat vehicles will be tele-operable. Video or Forward Looking Infrared (FLIR) sensors will be mounted on the vehicle, and imagery of the surrounding scene will be transmitted to a control station via a radio frequency (RF) link. However, visual imagery is a large user of bandwidth, and bandwidth on the battlefield is very limited. Therefore, a means must be found of achieving a low-data-rate transmission. We have developed a system that accomplishes this by using two distinct techniques. First, a 25-to-1 bandwidth reduction ratio is achieved by compressing the transmitted image using a combination of the Discrete Cosine Transform and Huffman encoding. Second, a 90-to-1 bandwidth reduction ratio is achieved by transmitting only one frame every 3 second rather than the usual 30 frames per second. The intervening 3 seconds are filled with 89 synthetically created frames (synthetic optic flow) which appear very much like those that would have been transmitted using full bandwidth transmission. The result of these two steps is an overall bandwidth reduction ratio of 25 X 90 equals 2250 to 1.