Research On Color Reduction Technology In Low Illumination Multispectral Color Imaging

In order to break through the limitation of low spectral utilization of traditional three-primary imaging devices under low illumination conditions.In this paper,a color imaging method based on the fusion of six primary colors with low light level under low illumination is proposed.Based on the twelve-primary color chromatographic sensitivity model of the compound eye structure of mantis shrimp,optimize and determine the six-primary color chromatographic system suitable for color low light imaging,in order to greatly improve the detection sensitivity,the six-primary color biomimetic chromatography system was chosen to introduce full-spectrum information in the visible light band.Combining the radiation energy spectrum of the standard light source,the quantum efficiency curve of the image sensor and the night sky light spectrum distribution curve,determine the optical parameters such as the central wavelength and bandpass width of the full-spectrum transparent filter for different primary colors and visible light bands.And design a color filter array with six primary colors plus full-spectrum transmission in the visible light band,and the selected array unit distribution is3×3.Establish a chromaticity conversion model to realize the chromatogram mapping from the six-primary color gamut to the RGB color space.Design and build a true color night vision system,the system components mainly include color filter arrays,image sensors and hardware circuits.Complete the true color night vision experiment and true color night vision system test under low illumination in the low-light laboratory,true color night vision experiment,that is,the acquisition of multi-band low-light images is completed through a monochrome camera+six primary colors and a full-light transmission filter lens in the visible light band,and the color reduction algorithm is written based on the six-primary color chromatographic mapping theory to achieve multi-band low light for image fusion,follow-up evaluation of its image quality and color reproduction,and continuous optimization of the algorithm based on the evaluation results.The true color night vision system test is to shoot the color card and landscape painting under the conditions of 5lx,5×10^-1lx,5×10^-2lx,and 5×10^-3lx to complete the video capture of the built true color night vision system,extract a single frame image from the captured video for image quality evaluation.The test results show that the true color night vision system built in this article is stable,able to achieve 25 frames/s color night vision image output,It can also work normally under the lowest working illumination5×10^-3lx and output color images with obvious color differences between targets.