Real-time image distortion correction based on FPGA

Abstract

As the primary method for real-time image processing, a field-programmable gate array (FPGA) is widely used in binocular vision systems. Distortion correction is an important component of binocular stereo vision systems. When implementing a real-time image distortion correction algorithm on FPGA, problems, such as insufficient on-chip storage space and high complexity of coordinate correction calculation methods, occur. These problems are analyzed in detail in this study. On the basis of the reverse mapping method, a distortion correction algorithm that uses a lookup table (LUT) is proposed. A compression with restoration method is established for this LUT to reduce space occupation. The corresponding cache method of LUT and the image data are designed. The algorithm is verified on our binocular stereo vision system based on Xilinx Zynq-7020. The experiments show that the proposed algorithm can achieve real-time and high precision gray image distortion correction effect and significantly reduce the consumption of on-chip resources. Enough to meet the requirements of accurate binocular stereo vision system.