Camera Control in Multi-Camera Systems for Video Quality Enhancement

Multiview video captured by multi-camera systems has been widely used in many applications such as surveillance, 3D television, and free viewpoint television. After capturing, the multi-camera system generally requires to compress a large amount of multiview data due to limitations on the transmission capacity. To improve video quality, previous work on video compression focused on algorithm refinements when a raw multiview video is compressed at a limited bit-rate, whereas existing work on instrumentation generally introduced higher resolution capture and additional hardware. In contrast, this paper uses camera control to enhance video quality. Individual cameras are controlled to adjust their pan angles and focal lengths to compensate for both object location difference and color inconsistency among camera views at the video acquisition stage. Such a compensation makes the camera images more similar and therefore improves the video quality when a raw multiview video is compressed at a limited bit-rate. The optimal pan angle and focal length are designed for each camera. An example application is to monitor a potted plant in real time for ornamental horticulture study. Experimental results validate the camera control method.