| Underwater resources are abundant,but due to the absorption and scattering of light,the application value of information contained is very low in traditional intensity camera images,which can not meet the needs of researchers.Therefore,it is an urgent problem to obtain relatively high definition images in this field.Compared with visible light images,polarized images have different polarization characteristics on the surface of different objects.To a certain extent,polarized images can distinguish the object from the actual background to improve the value of image utilization.In order to obtain more valuable information,polarized images can be fused by multi-scale transformation to enhance the image and improve the image quality.The main research contents of this paper are divided into two aspects: polarization imaging characteristics of underwater objects and image processing methods.Based on the theory of polarization optics,a series of underwater polarization imaging experiments are designed to study the underwater polarization imaging characteristics.By changing the target material,water depth,water turbidity and other variables by using the SALSA polarization camera under natural light.The effects of different material objects,placement depth,milk concentration and band factors on the polarization imaging of underwater objects were studied.The polarization component image is calculated,and the polarization imaging characteristics of different material objects in shallow water are objectively analyzed by comparing the polarization degree,contrast and information entropy of visible light image,polarization degree image and polarization component image.On the basis of underwater polarization imaging experiment,characteristic environment is set to collect visible light image and polarization image as the source images.Then the NSCT transformation will be used to decompose the images into multi-scale images.After that several different constraints are applied to the low-frequency coefficients and high-frequency coefficients.By comparing and analyzing the effect of fusion imaging,it is determined that the fusion image can enhance the source image. |
