نتایج جستجو برای: reflectance

تعداد نتایج: 19705  

2009
Jan Stuckens Willem W. Verstraeten Rony Swennen

The impact of target bidirectional reflectance in dual field of view spectroscopy was described and quantified using field measurements and ray-tracing simulations. A data-driven normalization method was developed to convert reflectance factors under cloud obscured conditions into clear sky reflectance by decomposing the target bidirectional reflectance into an isotropic target-specific compone...

2003
Takashi Machida Naokazu Yokoya Haruo Takemura

In mixed reality, especially in augmented virtuality which virtualizes real objects, it is important to estimate object surface reflectance properties to render the objects under arbitrary illumination conditions. Though several methods have been explored to estimate the surface reflectance properties, it is still difficult to estimate surface reflectance parameters faithfully for complex objec...

2002

Reflectance values for image-based relighting are often estimated from grouped pixels with similar reflectance, but such groupings are difficult to compute with certainty for sparse image data. To address this problem, we propose an iterative method that aggregates BRDF data in a single image with known geometry and lighting by soft grouping, where pixels contribute to one another’s estimate ac...

2002
Takashi Machida Naokazu Yokoya

In mixed reality, it is important to estimate object surface reflectance properties to render real objects under arbitrary illumination conditions. The authors developed a method to estimate reflectance properties of object surfaces densely. However, it was difficult to estimate surface reflectance properties faithfully for objects with interreflections. This paper describes a new method of den...

2006
Gabriela Schaepman-Strub Michael Schaepman Stefan Dangel Thomas Painter John Martonchik

Analysing databases, field and airborne spectrometer data, modelling studies and publications, it becomes obvious, that there is a lack of consistency in definitions of reflectance quantities throughout the imaging spectroscopy user community. One example is the term ‘BRDF’ assigned to significantly differing quantities, ranging from the bidirectional reflectance distribution function to hemisp...

Journal: :journal of agricultural science and technology 2010
s. k. alavi panah r. goossens

to use remote sensing data effectively, one must understand the spectral characteristics of the particular features under investigations. to study the relationship between soil salinity and soil reflectance, four multispectral scanners (mss) and seven thematic mappers (tm bands) over the ardakan playa located on the central iranian desert margins were selected. in this study soil map, soil ...

2010
C. Kobayashi O. Kashimura T. Maruyama M. Oyanagi I. C. Lau T. Cudahy D. Carter

In this study, to remove the effects of topography and surface roughness to observed spectrum initially, a method using the normalised reflectance (pseudoreflectance) was employed. Then, we examined the removal of the vegetation effects (such as green vegetation and dry vegetation) and a method to estimate soil pseudo-reflectance spectrum, because the ground surface shows the mixture of soil an...

Journal: :Optics letters 2009
N Brimhall N Heilmann M Ware J Peatross

We demonstrate a technique for determining optical constants of materials in the extreme UV from the ratio of p-polarized to s-polarized reflectance. The measurements are based on laser-generated high-order harmonics, which have easily rotatable linear polarization but that are prone to brightness fluctuations and systematic drifts during measurement. Rather than measure the absolute reflectanc...

2018
Kohei Arai

Optical property, such as spectral reflectance, bidirectional reflectance distribution functions and polarization characteristics of dried seaweeds is clarified together with an attempt for transparent foreign matter detection considering optical property of dried seaweeds, such as spectral transparency, bidirectional reflectance and transparency as well as polarimetric properties. Through expe...

2010
James D. Spinhirne

During the development of the Geoscience Laser Altimeter System (GLAS), launched in 2003, it was understood that the values of surface pusle reflectance was an important design parameter for satellite laser altimeters and that the magnitude of observed pulse reflectance would have valuable applications. Thus a significant effort was made to obtain calibrated surface pulse reflectance from GLAS ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید