Research On Real-time Processing Technology Of Short-wave Infrared Image Based On FPGA

Short-wave infrared imaging technology has become one of the main focuses in the development of infrared imaging technology today,having imaging characteristics that are not available in visible light and middle-wave and long-wave infrared imaging technology.It is widely used in fields such as marine monitoring,environmental monitoring,multi-spectral imaging analysis,and low-light-level night vision.However,there are some problems with the short-wave infrared imaging technology,the most notable of which are the non-uniformity and blind pixels of the output image.Besides,the contrast of image is low.These all have some effects on the quality of short-wave infrared images to some extent,which limits further development and application of the short-wave infrared imaging technology.Therefore,it is proposed to perform non-uniformity correction,blind pixels compensation,image enhancement and other related processing on the short-wave infrared image to improve the imaging quality of the short-wave imager.This paper mainly studies the implementation methods of real-time processing system of short-wave infrared image based on FPGA.And in response to the development requirements of high-resolution short-wave infrared imaging,a 1920×1080P HDMI high-speed serial interface based on FPGA is designed.This paper consists of following main parts:1)Based on the Vivado integrated development environment of Xilinx,non-uniformity correction module,blind pixels compensation module,image enhancement module and HDMI high-speed serial interface are achieved by using Verilog HDL language.In the design of the blind pixels compensation module,based on FPGA,a blind pixels compensation algorithm of selective median filtering is achieved.This method has a good compensation effect on both ordinary blind pixels and crossing dead pixels.In the design of the image enhancement module,a non-frequency-multiplied pipelined gray statistical method based on FPGA is adopted,which can simplify the digital logic design of the module and increase the operating frequency of the system.For short-wave infrared images with a resolution of 640 x 512,the total delay of the entire image processing system is 692 clock cycles,which can meet the requirements of real-time image processing.2)Use the 640 x 512 InGaAs short-wave infrared focal plane detector provided by Shanghai Institute of Technology and Physics,Chinese Academy of Science,and Artix-7 series FPGA chips of the Xilinx,to respectively carry out the validation experiment of the non-uniformity correction module,blind pixels compensation module and image enhancement module.The experimental results show that the functions of each module can meet the expected design requirements,which can effectively reduce the non-uniformity and blind pixels of the short-wave infrared image,and improve the image contrast.In the experiment,the blind rate of the original image was reduced from 0.497%to 0.005%,and the non-uniformity of the original image was reduced from 4.610%to 3.769%.3)Use the Artix-7 series FPGA chips of the Xilinx to verify functions of the designed HDMI high-speed serial interface.The experimental results show that the interface works normally when the serial data transmission rate is 1.485 Gbps,which meets the design requirements.