Research On Infrared Video Acquisition And Image Processing Algorithm Based On FPGA

In recent years,infrared imaging systems have been widely used in military,aerospace,communications,medicine and other fields.However,due to the influence of the infrared detector itself and the environment,infrared images have high noise,low contrast and other problems.Software-based image processing systems have been unable to meet too high real-time requirements.Therefore,it is of great significance to carry out research and implementation of real-time infrared programmable video gate array(FPGA)-based infrared video acquisition and image processing algorithms.The main research contents of this paper are as follows:Firstly,the imaging principle of the infrared imaging system and features of infrared image are introduced.Several image preprocessing algorithms are introduced.Including: an improved pulse filtering algorithm,an improved median filtering algorithm,a combination algorithm of gamma transformation and histogram equalization and an improved pseudo color transform algorithm.Simulation researches on the above different algorithms provides a theoretical basis for the subsequent FPGA-based implementation of related algorithms.Secondly,the FPGA-based infrared imaging system is built.The composition of the system is introduced.Designs and implementations of the infrared image acquisition,video decoder,data buffer,display and other modules are based on FPGA.And the ping-pong operation caching mechanism between different BANKs based on single-chip SDRAM is adopted to achieve continuous transmission of system video data.Then,the pseudo color conversion algorithm is implemented based on FPGA,including density layering method,linear transformation method and improved linear transformation method.At the same time,the temperature measurement principle of infrared imaging systems is studied,and the design and implementation of temperature measurement module and time display module are achieved.Finally,the image preprocessing algorithm proposed in the previous stage is implemented on FPGA,.The circuit scheme and hardware structure of the algorithm are introduced.The waveform simulation and board level verification are performed on the algorithm.At the same time,a comparison chart of the algorithm processing results is given.The research of this paper has important reference values for the design of the FPGA-based infrared imaging system.Through the further improvement,it is expected to obtain a low-cost,real-time infrared imaging system that can meet the needs of real-time infrared imaging systems in many occasions.