基于单传感器的低照度彩色图像增强系统

Low-Illumination Color Image Enhancement System Based on Single Sensor

针对低照度下传统彩色图像传感器成像质量差的问题,提出一种基于单传感器的低照度彩色图像增强系统。系统同时采集可见光(VIS)和近红外(NIR),用NIR对VIS图像进行增强。系统中,为处理混合光图像提出了一系列图像处理方法:针对NIR对VIS颜色干扰的问题,提出一种颜色差值与降噪处理相结合的VIS分离方法;针对VIS与NIR融合问题,提出一种色彩空间转换与标准化处理相结合的融合方法;针对颜色区分度与信噪比相矛盾的问题,提出一种比值图像与阈值设定相结合的像素替换方法。通过对低照度含NIR图像的处理表明,本文系统可以比较明显地提升传统彩色图像传感器在低照度下的成像亮度、信息量和信噪比,并且效果优于所对比文献。

To alleviate the problem of the poor imaging quality of conventional color image sensors under low illumination,a low-illumination color image enhancement system based on a single sensor was proposed.The system simultaneously collects visible(VIS)and near infrared(NIR)images and enhances the VIS image using the NIR image.In the system,a series of image processing methods were proposed to handle the mixed light images.These methods involved a VIS separation method combining color subtraction and noise reduction to eliminate the influence of NIR on VIS color,a fusion method combining color space conversion and standardization processing to fuse VIS and NIR images,and a pixel replacement method to solve the contradiction between color discrimination and signal-to-noise ratio.Through the image processing of low illumination using NIR,the system can significantly improve the brightness,information,and signal-to-noise ratio of conventional color image sensors under low illumination.