摘要
基于场景的非均匀校正依然是红外领域的一个研究热门。神经网络算法是一种较为典型的场景校正算法。本文主要针对神经网络算法本身不能校正光学引入的非均匀性问题,提出了新的改进算法,通过对神经网络输入层的预处理,消除图像的低频噪声,此外,为了消除预处理对图像对比度的影响,本文增加了神经网络的层数,使用双层神经网络对算法进行更新,从而消除了图像对比度下降的现象。实验结果表明,改进的神经网络算法能够有效的改善图像质量,消除图像中光学引入的非均匀性。
Scene-based non-uniformity correction is still a hot topic in the infrared field. A neural network algorithm is a classical scene-based non-uniformity correction algorithm. This article mainly introduced problems where the classical algorithm cannot correct an optical non-uniformity. We propose an improved algorithm based on the preprocessing layer to correct to the low-frequency noise. In order to eliminate the influence of the image contrast, we add a learning layer that can eliminate the image contrast drop phenomenon. The results of the experiment show that the new algorithm can effectively improve the image quality and eliminate non-uniformity introduced by the optics.
引文
[1]Boutemedjet A,Deng C,Zhao B.Robust Approach for Nonuniformity Correction in Infrared Focal Plane Array[J].Sensors,2016,16(11):1890.
[2]Scribner D A,Sarkady K A,Kruer M R,et al.Adaptive nonuniformity correction for IR focal-plane arrays using neural networks[C]//International Society for Optics and Photonics,1991:100-109.
[3]Torris S,Vera E,Reeves R.Adaptive Scene-based Nonuniformity Correction Method for Infrared Focal Plane Arrays[C]//Proceeding of SPIE,2003,5076:130-139
[4]Hardie R C,Baxley F,Brys B,et al.Scene-based nonuniformity correction with reduced ghosting using a gated LMS algorithm[J].Optics Express,2009,17(17):14918-14933.
[5]Celedon N,Redlich R,Figueroa M.FPGA-based Neural Network for Nonuniformity Correction on Infrared Focal Plane Arrays[J].Digital System Design,2012:193-200.
[6]RONG Shenghui,ZHOU Huixin,QIN Hanlin,et al.Nonuniformity correction for an infrared focal plane array based on diamond search block matching[J].J.Opt.Soc.Am A Opt.Image Sci.Vis,2016,33(5):938-946.
[7]牛英宇,聂瑞杰,李丽娟.基于FPGA的红外图像非均匀校正实现方法[J].激光与红外,2016,46(8):1028-1032.NIU Yingyu,NIE Ruijie,LI Lijuan.Non-uniformity correction for infrared image based on FPGA[J].Laser&Infrared,2016,46(8):1028-1032.
[8]LAI Rui,YANG Yintang,WANG Bingjian.A quantitative measure based infrared image enhancement algorithm using plateau histogram[J].Optics Communications,2010,283(21):4283-4288.