Image Correction Based on Field-Programmable Gate Array

In machine vision, to correct the distortion of image is required. For improving the performance of the real-time distortion, this paper proposes an algorithm that can compress the inverse mapping table while conduct on-line reconstruction for the inverse mapping table by using interpolation method on FPGA platform in order to overcome the problems that FPGA, when be used to implement algorithm correcting image distortion, will become complexity in the on-line computation of the inverse mapping coordinate and perform insufficient in the capacity of on-chip ROM. The inverse mapping table is used to obtain inverse mapping coordinates that reduce both the amount of on-line computation of FPGA and the need of capacity of on chip ROM. The simulation on MATLAB show the results that when the compression parameters n is 4, 8, or 16, the distortion image can be corrected well and the information will not be lost. A FPGA-based double-sided visual image acquisition platform is built, and the algorithm is tested on the platform. Results show that the proposed algorithm can correct the nonlinear distortion of the image well.