Improved Non-uniformity Correction Method by Pixel-wise Radiometric Self-calibration for Infrared Imaging
-
摘要: 红外成像系统中一直存在着非均匀性的问题,针对红外大动态范围成像等任务对改变成像系统积分时间的需要,提出了一种利用像素级辐射自校正技术的可变积分时间的非均匀性校正方法。通过辐射自校正为红外探测器中的每个像元建立辐射响应方程以估计出场景的辐射通量图,利用线性校正模型对辐射通量图进行校正,实现任意积分时间下的非均匀性校正。该方法的有效性通过高分辨率碲镉汞红外探测器进行了验证。Abstract: Eliminating non-uniformity is a persistent challenge for infrared imaging systems, especially when the integration time varies. This paper describes a non-uniformity correction method with the ability to adapt to arbitrary changes in integration time by correcting the infrared radiation flux map of the scene, which is estimated by pixel-wise radiometric self-calibration. Multiple images of an extended blackbody, obtained with different integration times and blackbody temperatures, were used to obtain the parameters of both the correction model and radiometric calibration model. The correction effect of this method within a wide range of integration times was verified by a high-resolution HgCdTe medium-wave infrared imager.
-
表 1 3种方法处理前后的黑体图像的NU的统计数据
Table 1. NU statistics of the black body image before and after process of the three methods
Method Mean NU Median NU Min NU Max NU Un-corrected 6.041% 6.489% 3.025% 8.583% Two-point 1.562% 1.081% 0.088% 6.024% Ochs 0.133% 0.128% 0.073% 0.281% Proposed 0.101% 0.098% 0.050% 0.205% 表 2 三种方法处理前后的场景图像的粗糙度ρ
Table 2. Roughness ρ of the scene images before and after theprocess of the three method
Integration Time/ms Un-corrected Two-point Ochs Proposed 4 0.11816 0.01032 0.00924 0.00904 9 0.07297 0.00998 0.00900 0.00890 12 0.06285 0.00989 0.00888 0.00876 -
[1] 蔡盛, 柏旭光, 乔彦峰. 基于标定的IRFPA非均匀性校正方法综述[J]. 红外技术, 2007, 29(10): 589-592. doi: 10.3969/j.issn.1001-8891.2007.10.008CAI Sheng, BAI Xuguang, QIAO Yanfeng. Summarize on the Nonuniformity Correction Algorithms for IRFPA Based on Calibration[J]. Infrared Technology, 2007, 29(10): 589-592. doi: 10.3969/j.issn.1001-8891.2007.10.008 [2] Scribner D A, Sarkady K A, Caulfield J T, et al. Nonuniformity correction for staring IR focal plane arrays using scene-based techniques[C]//Infrared Detectors and Focal Plane Arrays. International Society for Optics and Photonics, 1990, 1308: 224-233. [3] 周永康, 朱尤攀, 赵德利, 等. 基于场景的红外焦平面非均匀校正算法综述[J]. 红外技术, 2018, 40(10): 952-960. https://www.cnki.com.cn/Article/CJFDTOTAL-HWJS201810005.htmZHOU Yongkang, ZHU Youpan, ZHAO Deli, et al. A Review of Scene-based Nonuniformity Correction Algorithms for Infrared Focal Plane Arrays[J]. Infrared Technology, 2018, 40(10): 952-960. https://www.cnki.com.cn/Article/CJFDTOTAL-HWJS201810005.htm [4] 洪闻青, 姚立斌, 姬荣斌, 等. 基于不同积分时间帧累加的红外图像超帧方法[J]. 光学精密工程, 2016, 24(6): 1490-1500. https://www.cnki.com.cn/Article/CJFDTOTAL-GXJM201606032.htmHONG Wenqing, YAO Libin, JI Rongbin, et al. A super-frame processing method for infrared image based on accumulation of different integration time frame[J]. Optics and Precision Engineering, 2016, 24(6): 1490-1500. https://www.cnki.com.cn/Article/CJFDTOTAL-GXJM201606032.htm [5] CHEN N, ZHANG J, ZHONG S, et al. Nonuniformity Correction for Variable-Integration-Time Infrared Camera[J]. IEEE Photonics Journal, 2018, 10(6): 1-11. http://www.zhangqiaokeyan.com/academic-journal-foreign_other_thesis/0204112541971.html [6] LIU M, LI S, LI L, et al. Infrared HDR image fusion based on response model of cooled IRFPA under variable integration time[J]. Infrared Physics & Technology, 2018, 94: 191-199. http://www.sciencedirect.com/science/article/pii/S1350449518303207 [7] 白乐, 赖雪峰, 韩维强, 等. 适应积分时间调整的红外图像非均匀性校正方法[J]. 光子学报, 2020, 49(1): 0110002. https://www.cnki.com.cn/Article/CJFDTOTAL-GZXB202001020.htmBAI Le, LAI Xuefeng, HAN Weiqiang, et al. Infrared Image Nonuniformity Correction Method Adapted to Adjustment of Integration Time[J]. ACTA Photonica Sinica, 2020, 49(1): 0110002 https://www.cnki.com.cn/Article/CJFDTOTAL-GZXB202001020.htm [8] Ochs M, Schulz A, Bauer H J. High dynamic range infrared thermography by pixelwise radiometric self calibration[J]. Infrared Physics & Technology, 2010, 53(2): 112-119. http://www.sciencedirect.com/science/article/pii/S1350449509001303 [9] Rogalski A. Infrared Detectors[M]. Boca Raton, FL: CRC press, 2010. [10] EMVA 1288 Working Group. EMVA Standard 1288–Standard for Characterization of Image Sensors and Cameras, Release 3.1[S].[2020-04-20], 2016. [11] Mitsunaga T, Nayar S K. Radiometric self calibration[C]//Proceedings. 1999 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 1999, 1: 374-380. [12] Mooney J M, Sheppard F D, Ewing W S, et al. Responsivity nonuniformity limited performance of infrared staring cameras[J]. Optical Engineering, 1989, 28(11): 281151. http://adsabs.harvard.edu/abs/1989opten..28.1151m [13] Majeed M Hayat, Sergio N Torres, Ernest Armstrong, et al. Statistical algorithm for nonuniformity correction in focal-plane arrays[J]. Applied Optics, 1999, 38: 772-780. doi: 10.1364/AO.38.000772