Dual-mode Catadioptric Omnidirectional Imaging System Based on Feedback Controlled Image-Sampling

In order to resolve the conflict between the resolution and frame rate of omnidirectional imaging systems, a dual-mode (global & local) catadioptric omnidirectional imaging system is designed and implemented, by feedback controlling the sampling configurations of image sensor.In global mode, annular omnidirectional images are captured by using skip subsampling mode to guarantee high frame rate, and then unwrapped to cylindrical panoramic images containing global scene information of 360 degrees.In local mode, the location and size of sampling window of image sensor are reconfigured according to the position of interested region, thereby only a corresponding rectangle region of omnidirectional images is captured by using pixel-by-pixel mode, and then unwrapped to a high-definition local perspective image of the corresponding view angle.Finally, a hardware design based on DSP+FPGA is presented.Experimental results indicate the validity and practicability of our design.