Diffuse sky radiation
View article: A Fast Single Image Haze Removal Algorithm Using Color Attenuation Prior
A Fast Single Image Haze Removal Algorithm Using Color Attenuation Prior Open
Single image haze removal has been a challenging problem due to its ill-posed nature. In this paper, we propose a simple but powerful color attenuation prior for haze removal from a single input hazy image. By creating a linear model for m…
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Atmospheric Correction for Satellite Ocean Color Radiometry Open
This tutorial is an introduction to atmospheric correction in general and also documentation of the atmospheric correction algorithms currently implemented by the NASA Ocean Biology Processing Group (OBPG) for processing ocean color data f…
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A Cascaded Convolutional Neural Network for Single Image Dehazing Open
Images captured under outdoor scenes usually suffer from low contrast and limited visibility due to suspended atmospheric particles, which directly affects the quality of photographs. Despite numerous image dehazing methods have been propo…
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Single image dehazing via an improved atmospheric scattering model Open
Under foggy or hazy weather conditions, the visibility and color fidelity of outdoor images are prone to degradation. Hazy images can be the cause of serious errors in many computer vision systems. Consequently, image haze removal has prac…
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Polarization patterns under different sky conditions and a navigation method based on the symmetry of the AOP map of skylight Open
The polarization states of a skylight can be used for navigation by a lot of insects as well as by human beings. However, the polarization patterns of skylight are greatly influenced by the atmospheric conditions. This paper studied the po…
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Atmospheric Light Estimation Based Remote Sensing Image Dehazing Open
Remote sensing images are widely used in object detection and tracking, military security, and other computer vision tasks. However, remote sensing images are often degraded by suspended aerosol in the air, especially under poor weather co…
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Study of Sea Fog Environment Polarization Transmission Characteristics Open
Sea fog is a particular kind of atmospheric aerosol that often poses hidden risks to ship navigation, ocean exploration, human productivity, and life. In light of the aforementioned issues, this research conducted a thorough investigation …
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Laser Beam Atmospheric Propagation Modelling for Aerospace LIDAR Applications Open
Atmospheric effects have a significant impact on the performance of airborne and space laser systems. Traditional models used to predict propagation effects rely heavily on simplified assumptions of the atmospheric properties and their int…
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Single Image Dehazing via Large Sky Region Segmentation and Multiscale Opening Dark Channel Model Open
Outdoor images acquired under poor weather conditions are usually contaminated by suspended particles and aerosols in the atmosphere. These captured images easily suffer from contrast reduction, low visibility, and color distortion. In thi…
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Novel robust skylight compass method based on full-sky polarization imaging under harsh conditions Open
A novel method based on Pulse Coupled Neural Network(PCNN) algorithm for the highly accurate and robust compass information calculation from the polarized skylight imaging is proposed,which showed good accuracy and reliability especially u…
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Comparison of aerosol properties retrieved using GARRLiC, LIRIC, and Raman algorithms applied to multi-wavelength lidar and sun/sky-photometer data Open
Aerosol particles are important and highly variable components of the terrestrial atmosphere, and they affect both air quality and climate. In order to evaluate their multiple impacts, the most important requirement is to precisely measure…
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Atmospheric extinction coefficient retrieval and validation for the single-band Mie-scattering Scheimpflug lidar technique Open
An 808 nm single-band Mie scattering Scheimpflug lidar system is developed in Dalian, Northern China, for real-time, large-area atmospheric aerosol/particle remote sensing. Atmospheric measurement has been performed in urban area during a …
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Solar Radiation: Practical Modeling for Renewable Energy Applications Open
Written by a leading scientist with over 35 years of experience working at the National Renewable Energy Laboratory (NREL), Solar Radiation: Practical Modeling for Renewable Energy Applications brings together the most widely used, easily …
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An automated cloud detection method based on the green channel of total-sky visible images Open
Obtaining an accurate cloud-cover state is a challenging task. In the past, traditional two-dimensional red-to-blue band methods have been widely used for cloud detection in total-sky images. By analyzing the imaging principle of cameras, …
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Multiple scattering contribution to the diffuse light of a night sky: A model which embraces all orders of scattering Open
The mechanism in which multiple scattering influences the radiance of a night sky has been poorly quantified until recently, or even completely unknown from the theoretical point of view. In this paper, the relative contribution of higher-…
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Validation of a spectral correction procedure for sun and sky reflections in above-water reflectance measurements Open
A three-component reflectance model (3C) is applied to above-water radiometric measurements to derive remote-sensing reflectance Rrs (λ). 3C provides a spectrally resolved offset Δ(λ) to correct for residual sun and sky radiance (Rayleigh-…
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UV Irradiance Enhancements by Scattering of Solar Radiation from Clouds Open
Scattering of solar radiation by clouds can reduce or enhance solar global irradiance compared to cloudless-sky irradiance at the Earth’s surface. Cloud effects to global irradiance can be described by Cloud Modification Factors (CMF). Dep…
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A Fast Single-Image Dehazing Method Based on a Physical Model and Gray Projection Open
Due to the scattering of atmospheric particles, images captured under hazy conditions suffer from contrast attenuation and color distortion, which severely affect the performance of machine vision systems. Various types of methods have bee…
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Technique to separate lidar signal and sunlight Open
Sunlight contamination dominates the backscatter noise in space-based lidar measurements during daytime. The background scattered sunlight is highly variable and dependent upon the surface and atmospheric albedo. The scattered sunlight con…
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Spectral sea surface reflectance of skylight Open
In examining the dependence of the sea surface reflectance of skylight ρs on sky conditions, wind speed, solar zenith angle, and viewing geometry, Mobley [Appl. Opt.38, 7442 (1999).10.1364/AO.38.007442] assumed ρs is independent of wavelen…
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Atmospheric extinction in solar tower plants: absorption and broadband correction for MOR measurements Open
Losses of reflected Direct Normal Irradiance due to atmospheric extinction in concentrated solar tower plants can vary significantly with site and time. The losses of the direct normal irradiance between the heliostat field and receiver in…
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Polarized reflectance and transmittance distribution functions of the ocean surface Open
Two aspects of ocean modelling are treated: representation of ocean waves considering all size-classes of waves and tracing of light-interactions at the wavy sea surface. Nonlinear wave profiles are realized accounting for a wide range of …
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An Evaluation of Skylight Polarization Patterns for Navigation Open
Skylight polarization provides a significant navigation cue for certain polarization-sensitive animals. However, the precision of the angle of polarization (AOP) of skylight for vehicle orientation is not clear. An evaluation of AOP must b…
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Atmospheric CO_2 column measurements in cloudy conditions using intensity-modulated continuous-wave lidar at 157 micron Open
This study evaluates the capability of atmospheric CO2 column measurements under cloudy conditions using an airborne intensity-modulated continuous-wave integrated-path-differential-absorption lidar operating in the 1.57-μm CO2 absorption …
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Non-sky polarization-based dehazing algorithm for non-specular objects using polarization difference and global scene feature Open
Photographic images taken in foggy or hazy weather (hazy images) exhibit poor visibility and detail because of scattering and attenuation of light caused by suspended particles, and therefore, image dehazing has attracted considerable rese…
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Long range 3D imaging through atmospheric obscurants using array-based single-photon LiDAR Open
Single-photon light detection and ranging (LiDAR) has emerged as a strong candidate technology for active imaging applications. In particular, the single-photon sensitivity and picosecond timing resolution permits high-precision three-dime…
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A Fast Single-Image Dehazing Algorithm Based on Dark Channel Prior and Rayleigh Scattering Open
The scattering of atmospheric particles significantly alters images captured under hazy weather condition. Images appear distorted, blurry and low in contrast attenuation, which extensively affects computer vision systems. There has been d…
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SPEXone: a compact multi-angle polarimeter Open
We have developed a 6 dm3-sized optical instrument to characterize the microphysical properties of fine particulate matter or aerosol in the Earth atmosphere from low Earth orbit. Our instrument can provide detailed and worldwide knowledge…
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Low-pass filtering based polarimetric dehazing method for dense haze removal Open
Polarimetric dehazing method is very promising in enhancing the quality of images captured in the scattering media. However, it is found that the dehazing results calculated by hazy images are very sensitive to the noise, which may cause t…
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Angle of linear polarization images of outdoor scenes Open
Observations from the Ground-based Multiangle SpectroPolarimetric Imager (GroundMSPI) are used to relate angle of linear polarization (AoLP) measurements to material properties and illumination conditions in sunlit outdoor environments. Gr…