update background image meaning in English

(更新背景)：该命令在重新设置背景，设置参数，设置视窗纵横比等后，进行更新。
更新背景图像

Upon the background of detecting and tracking moving vehicles in an intelligent video - based road traffic surveillance system , in this thesis , we focus our research on some hard issues in detecting moving objects , such as updating background image , eliminate the disturbances of moving cast shadow and vehicle headlight , and propose a robust algorithm of detecting and tracking moving vehicles on road . we also apply our algorithm to an applicable road traffic monitoring system
本文以智能化视频道路交通监测系统中运动车辆的检测与跟踪为应用背景，对运动目标检测中背景更新、阴影和车灯投影噪声的消除等一些难点问题进行了深入的分析研究，提出了一个稳定的运动车辆检测和跟踪的算法，并在此基础上完成了实用的视频道路交通监测系统的设计与开发。
The main contents can be listed as follows : 1 . after analyzing the properties of the natural illuminating system , a region - based background and natural illumination model is set up using the histogram of image difference and rls filter . on the basis of that model , we propose an adaptive algorithm of judging and updating background image
基于户外自然光照系统的特点，建立了基于图像差分直方图和递推最小二乘滤波（ recursiveleastsquarefilter ,简称rls滤波器）的局域化背景和光照变化模型，提出了自适应的背景判断和更新算法。