Research On Four-band Image Color Correction Algorithm Based On Ridge Regression

For the image color cast problem caused by the near-infrared light mixed in the image captured in the visible light range,the traditional monitoring system uses a mechanically switched infrared cut filter to switch the day/night shooting mode,but this is prone to mechanical failure and affects imaging.To solve this problem,on the basis of not changing the original CCD or CMOS sensor,this thesis adopts the 850 nm double-peak filter to replace the traditional mechanically switched infrared filter.At night,850 nm near-infrared light can be used for imaging.In addition to visible light imaging during the day,there is also 850 nm near-infrared light that affects the color of the image.In this thesis,we call such a color cast image as a four-band image.In order to solve the problem of four-band image color cast caused by infrared interference,this thesis abandons the traditional infrared interference image color cast correction analysis method,Rather,according to the visual characteristics of the human eye color,the image sensor of the imaging device is analyzed to acquire a four-band image process for correction.Combined with the definition of four-band image,this thesis points out that one of the important factors that cause the color shift of the four-band image is that the 850 nm near-infrared light has exceeded the original visible-band spectral response function expression range of the sensor,After passing the spectral response function,it will get a response that does not meet the human eye's perceived color characteristics,And the response values are superimposed on the R,G,and B channels respectively,causing image color cast.According to the factors causing the color cast of the four-band image,the control variable method is used to construct the three-band image and the four-band image imaging environment,and then the regression relationship between the three-band image and the four-band image is constructed.The color correction matrix is obtained by the color calibration method of ridge regression to compensate the response of the spectral response function of the camera image sensor to the 850 nm near-infrared light error,so as to achieve the purpose of color correction of the four-band image.Experiments show that this method can correct the different four-band images in different illumination environments,which has certain reference value for image color correction which is affected by infrared light.