Implementation Of Infrared Thermal Imaging System And Research Of Its Image Enhancement Technology

With the development of infrared thermal imaging technology, infrared imaging has been widely used in many fields, such as military, medical, navigation and remote sensing, which exhibits potential application prospects. Constrained by current technology and materials lead, infrared detectors have a series of defect, such as non-uniformity, dead pixel and blur, which impair the quality of images significantly. However, under the condition of current science technology, it is difficult to eliminate these problems by improving the manufacturing processes and techniques of detection devices. Therefore, the impairments can been reduced effectively by real-time image processing. The FPGA and other programmable logic devices were widely used in infrared imaging system to process the real-time image stream because of their ability of high-speed parallel and pipelined processing. To eliminate non-uniformity, dead pixel, and blur problems of the image, a novel implementation scheme of infrared thermal imaging system with its implement was present.Firstly, the background and status of infrared thermal imaging and image enhancement technology were introduced. Meanwhile, the general design model of infrared thermal imaging system is described. To solve the problem of non-uniformity and image blurring in infrared thermal imaging systems, several corresponding processing algorithms were illustrated. The two-point calibration algorithm based on the same uniform radiation is used to solve the image non-uniformity. The histogram equalization algorithm was involved to reduce image blur. The adaptive neighbor interpolation algorithm was introduced to eliminate the dead pixel problems.Secondly, based on static and dynamic consumption resources evaluating, a reasonable infrared thermal imaging system and its implementation was present in detail. The main works was discussed successively: 1) The designing of infrared focal plane array detector interface in infrared image acquisition module, 2) The real-time stream processing algorithm and its implementation, such as pipeline and Ping-Pong buffer mechanism, and the design of PAL(Phase Alteration Line) system. The feasibility and correctness of the system were verified by system test results.Finally, the phenomenon of local details losses during the imaging process was discussed. The digital detail enhancement algorithm proposed by FLIR, made it possibly to maintain a well local image details and noise suppression simultaneously. An improved image enhancement algorithm is presented in this paper. The simulation results show that this algorithm exhibits a satisfied performance.