Dehazing method through polarimetric imaging and multi-scale analysis

Abstract

An approach for haze removal utilizing polarimetric imaging and multi-scale analysis has been developed to solve one problem that haze weather weakens the interpretation of remote sensing because of the poor visibility and short detection distance of haze images. On the one hand, the polarization effects of the airlight and the object radiance in the imaging procedure has been considered. On the other hand, one fact that objects and haze possess different frequency distribution properties has been emphasized. So multi-scale analysis through wavelet transform has been employed to make it possible for low frequency components that haze presents and high frequency coefficients that image details or edges occupy are processed separately. According to the measure of the polarization feather by Stokes parameters, three linear polarized images (0°, 45°, and 90°) have been taken on haze weather, then the best polarized image min I and the worst one max I can be synthesized. Afterwards, those two polarized images contaminated by haze have been decomposed into different spatial layers with wavelet analysis, and the low frequency images have been processed via a polarization dehazing algorithm while high frequency components manipulated with a nonlinear transform. Then the ultimate haze-free image can be reconstructed by inverse wavelet reconstruction. Experimental results verify that the dehazing method proposed in this study can strongly promote image visibility and increase detection distance through haze for imaging warning and remote sensing systems.

Review of passive polarimetric dehazing methods

“…Then, the high spatial frequency components are manipulated with a nonlinear transform. 64,83 The corresponding dehazing results are shown in Fig. 15.…”

Active non-line-of-sight imaging through dense fog via hybrid intelligent enhancement perception system

“…Thus, polarization dehazing techniques offer broader applicability and lower cost. Currently, polarization dehazing techniques are primarily classified into passive polarization dehazing techniques 2,3,19 and active polarization dehazing techniques. 4 Optical fog-penetrating techniques based on the ToF principle are also a mainstream approach in the optical field.…”

“…Existing penetration methods mainly focus on optics and computer vision domains. In the optical field, physical characteristics of light such as wavelength 1 and polarization, [2][3][4] TOF-based range-gated imaging, 5,6 liDAR based single-photon detection 7 and other methods are mainly used to obtain occlusions target signals. However, in scenarios with high optical thickness of dense fog, the weak echo photon count from the target object, coupled with limitations in detector sensitivity and time resolution, makes it challenging to achieve efficient imaging of target scenes obstructed by dense fog.…”

Advanced Visualization Polarimetric Imaging: Removal of Water Spray Effect Utilizing Circular Polarization

“…Techniques for imaging through turbid media have recently received considerable attention because of their potential applications such as atmosphere remote sensing, underwater photography, and even biomedical imaging [1][2][3]. The major difficulty encountered in these techniques is the loss of directionality of the incident light caused by multiple scattering among particles (water spray, dust, etc.…”