基于直方图分布的航天相机动态范围调整方法  

Dynamic Range Adjustment Method of the Aerospace Camera Based on Histogram Distribution

作　　者：李春梅[1] 郭元荣[1] 董书莉[1] 胡雨婷 张斐然[1] 

机构地区：[1]北京空间机电研究所,北京100094

出　　处：《航天返回与遥感》2017年第5期36-43,共8页Spacecraft Recovery & Remote Sensing

基　　金：国家重大科技专项工程

摘　　要：动态范围自动调整对航天相机有重要意义,尤其是相机动态范围调整频繁,实时性要求较高时,需要动态范围实时自动调整才能满足要求。以灰度均值、最值作为动态范围调整的依据,都缺乏对图像信息分布的整体理解;而以图像熵作为图像动态范围调整的依据,效率不足。为此,文章提出了基于直方图分布特征的相机动态范围自动调整方法。该方法在统计图像直方图的基础上,进一步实施直方图信息提取,设计了直方图区域面积函数作为动态范围评价依据,并给出动态范围调整策略,调整的目的是使图像直方图更接近于理想的分布。基于直方图分布特征的方法相较于灰度均值、最值和图像熵的方法,能得到更优的调整效果。经大量实验验证,基于直方图分布特征的相机动态范围自动调整方法,能够获得较好的相机动态范围调整效果,且效率较高,运行稳定。It is very important for the aerospace camera to adjust the dynamic range automatically. Especially when the camera dynamic range requires high-frequency and real-time adjustments, the automatic adjustment of dynamic range will be indispensable. Methods using image gray scale average or maximum value as the basis of dynamic range adjustment, lack understanding the overall image information distribution, and methods using image entropy as the basis are inefficient in computing. Therefore, a new automatic adjustment method of camera dynamic range was proposed based on histogram distribution characteristics in this paper. On the basis of gathering image histogram, the information of histogram was further extracted in this method. A histogram regional area function was designed as the evaluation criterion of dynamic range, and then the dynamic range adjustment strategy was given according to this function. The purpose of adjustment was to make the image histogram closer to ideal distribution. Better performance can be achieved by the proposed method in this paper than those three ones mentioned previously. Lots of experiments showed that the automatic adjustment method of camera dynamic range based on histogram distribution characteristics can obtain better dynamic range adjustment results with high efficiency and stability.

关 键 词：直方图 动态范围 自动调整 评价依据 航天相机 

分 类 号：TN401[电子电信—微电子学与固体电子学]