Development Of Aerospace Camera Image Qualit Testing System Based On Transfer Function Method

As an important equipment for obtaining information in the aerospace field,the quality of the imaging quality of aerospace cameras installed on different types of aircraft will have a direct impact on the observation effect and observation accuracy of the target.Therefore,the camera needs to be test and evaluate the image quality.This thesis aim at the problems of low image quality detection efficiency and large personnel error of existing aerospace cameras,based on a full understanding of traditional image quality testing methods,a calculation method based on transfer function is given to evaluate the image quality of aerospace cameras;at the same time,in order to meet the requirements of the real-time image transmission of the test system,a real-time image data transmission interface design based on the Gigabit Ethernet protocol was carried out.This test system development,the main contents involved are:the FPGA hardware platform is used to implement the Gigabit Ethernet protocol,and the camera image data is transmitted to the computer side at high speed;an algorithm program for UDP-oriented Socket socket for image acquisition,the image RAW format is converted into a BMP bitmap file for image display,and edge detection and Hough transform is used to complete image posture correction and other related functions has been compiled;in the calculation of modulation transfer function(MTF)value,the measurement method of contrast is used to realize the numerical calculation of MTF;in the laboratory environment,a camera performance test system platform was built,using different models of cameras to shoot rectangular targets in the system,obtaining fringe images to calculate MTF values,and comparing and analyzing with manual MTF test results;the factors that affect the accuracy of the system test results are analyzed and corresponding solutions are given.Experimental test results show that the test system can obtain MTF values more accurately,greatly improve the test efficiency,and achieve the performance test requirements for the imaging quality of aerospace cameras.