Scene-based Infrared Focal Plane Non-uniformity Correction Algorithm And FPGA Implementation

In recent years,infrared thermal imaging technology is developing rapidly,infrared focal plane array as the core device of today's mainstream infrared imaging system,its quality directly impacts on the infrared image imaging quality.Due to the production of raw materials,processing technology and other issues,the presence of infrared focal plane array inherent non-uniformity,through it needs to be solved by the signal processing algorithms.At home and abroad focus on the non-uniformity correction algorithm do a lot of research work.The scene-based non-uniformity correction algorithm has become a research hotspot in recent years because of its own advantages.At present,the hardware implementation of scene-based correction algorithm is mainly confronted with two problems:The complexity of the algorithm is large and the hardware implementation is restricted;Easy to produce ghosting.In this paper,we focus on the above two points on the scene-based non-uniformity correction algorithm was studied and implemented based on an FPGA hardware platform infrared focal plane non-uniformity correction system.In this paper,infrared imaging hardware system based on scene-based infrared focal plane non-uniformity correction algorithm is designed,which includes the selection of the main processing chip FPGA,the hardware and software drivers of the infrared focal plane array,design of AD and DA conversion module.It is studied and realized that the blind element processing and image enhancement module of infrared imaging system.Blind element processing module uses dual reference emitter detection algorithm and neighborhood replacement algorithm to remove most of the blind spot noise,effectively improve the image imaging quality.The image enhancement module adopts the platform histogram equalization algorithm,which greatly improves the image contrast and enhances the image visibility.It analyzed the classic neural network algorithm based on scene and its shortcomings.And an improved scene-based non-uniformity correction algorithm is proposed.And the advantages and disadvantages of the classical neural network correction algorithm and the improved correction algorithm are compared and analyzed from the aspects of image clarity,non-uniformity and ghost suppression.The improved non-uniformity correction algorithm based on scene is implemented on the FPGA platform.The calibration algorithm module includes the sampling matrix window module,the real-time read and write parameters of calibration parameters and the correction algorithm module.After testing,the algorithm realizes the correction of the real-time infrared video on the hardware platform of the infrared focal plane array imaging system.The algorithm can quickly remove the non-uniformity noise in the infrared image and greatly improve the imaging effect of the infrared image,at the same time,suppress the generation of the ghosting effectively.