CMOS图像传感器自动白平衡算法及其FPGA实现.pdf

航天返回与遥感
第37卷第3期
SPACECRAFT RECOVERY&REMOTE SENSING
2016年6
CMOS图像传感器自动白平衡算法及其
FPGA实现
董国伟侯作勋王震潘铮刘明关晨辉
(北京空间机电研究所,北京100094)
摘要为提高图像处理效果和处理速度,使处理后图像颜色与人眼视觉主观感受到的颜色保持一
致,文章提出了一种改进的自动白平衡算法。该方法以灰度世界法和全反射理论法为基础,通过自动评
估图像的色彩丰富性并确定相应的规则动态选取优势算法进行处理。设计实现了相应的FPGA处理模块
通过采用高效的并行流水线技术,充分考虑硬件模块内部潜在的并行度,确保系统的实时处理能力。文
章算法的优势在于对图像的自适应性和计算的快速性。对不同场景图像,该方法产生不同的值参数,
进而选取不同的优势算法,确保系统的自适应性;对高速视烦图像,该方法建立了一个简化的优势算法
选取规则,有利于FPGA硬件电路的实现,从而保证了计算的快速性。仿真试验表明,基于该算法设计
实现的FPGA硬件处理系统,对不同的场景均取得较好的处理效果,针对分辨率为1920像元x×1080像元
的视图像,达到了优于25帧s的实时处理速度。该算法硬件电路开销少,实时性好,适应性强,能有
效提高图像品质,具有广阔的应用前景。
关键词图像传感器自动白平衡算法现场可编程门阵列航天遥感
中图分类号:TN2
文献标志码:A
文章编号:1009-8518(2016)03-0082-09
DOI:10.3969%1.iss.1009-8518.2016.03.010
Design and FPGA Implementation of Auto White Balance
Method for CMOS Image Sensor
DONG Guowci HOU Zuoxun WANG Zhen PAN Zhcng LIU Ming GUAN Chenhui
Beijing Institute of Space Mechanics &Electricity, Beijing 100094, China
Abstract In order to improve image processing quality and boost processing rate so that the processed
images colors become as same as the colors of human vision feeling, the paper proposes a kind of improved
auto white balance method for CMOS camera image processing system. The proposed method is based on the
gray world method and the perfect reflector method, and il can choose the proper method belween the above
two methods automatically by estimating the richness of color in the images. The corresponding FPGA
processing modules are designed to implement the methods. Especially, the high-performance parallel pipelined
tcchnology and thc inncr potcntial parallcl proccssing ability of the modules cnsurc the Ical-timc proccssing
ability o the complele camera system. The advantages of method mentioned In this article are adaptability and
fast proccssing ratc. This mcthod has diffcrcnt threshold paramcters for diffcrcnt sccncs with appropriate
algorithm for each scene to ensure adaptability. Also, it set up a simplified algorithm selecting rules for high
spccd vidco whose hardwarc is casicr to mplcmcnt on FPGA which can guarantee fastcr proccssing rate. The
simulations and the experiments show that the FPGA system implemented the proposed method can achieve the
收稿日期:2016-03-02