Shadow effects have drawn much attention by researchers with increasing use of high-resolution remote sensing images of urban areas. For correction or compensation to pixels that falling in shadow areas due to the existence of vertically standing objects such as buildings and trees, quantitative analysis of shadow effects is essential. In this paper, we proposed an object-based approach for pre...

We consider mean curvature flow of an initial surface that is the graph a function over some domain definition in $R^n$. If not complete then we impose constant Dirichlet boundary condition at surface. establish longtime-existence and investigate projection flowing onto $R^n$, shadow flow. This moving can be seen as weak solution for hypersurfaces $R^n$ with condition. Furthermore, provide lemm...

This paper presents a methodology to automatically detect and remove the shadows in high-resolution urban aerial images for urban GIS applications. The system includes cast shadow computation, image shadow tracing and detection, and shadow removal. The cast shadow is computed from digital surface model (DSM) and the sun altitudes. Its projection in the pseudo orthogonal image is determined by r...

We present an algorithm for artistically modifying physically based shadows. With our tool, an artist can directly edit the shadow boundaries in the scene in an intuitive fashion similar to freeform curve editing. Our algorithm then makes these shadow edits consistent with respect to varying light directions and scene configurations, by creating a shadow mesh from the new silhouettes. The shado...

Shadows are important to computer graphics because they add realism and help the viewer identify spatial relationships. Shadows are also useful story-telling devices. For instance, artists carefully choose the shape, softness, and placement of shadows to establish mood or character. Many shadow generation techniques developed over the years have been used successfully in offline movie productio...

Shadow Information Technology (IT) occurs when users develop systems outside of the central information technology department. It provides both benefits and risks. Users procuring shadow IT often do not consider integration with existing enterprise architecture, privacy and security protection, maintenance cost, and legal ramifications. Problems with shadow IT must often be resolved by central ...

We present a hybrid algorithm for rendering hard shadows accurately and efficiently. Our method combines the strengths of shadow maps and shadow volumes. We first use a shadow map to identify the pixels in the image that lie near shadow discontinuities. Then, we perform the shadow-volume computation only at these pixels to ensure accurate shadow edges. This approach simultaneously avoids the ed...

* The author is a Senior Economic Affairs Officer at the Development Policy Analysis Division of UN DESA. He would like to thank Gregroy Mikkelson and Danny Dorling for their comments on previous versions the paper. Thanks are also due to the participants of the Expert Group Meeting held in 2014 where this paper was presented. Particular thanks are due to the anonymous referee, whose substantiv...

In hyperspectral imagery, differences in ground surface structures cause a large variation the optical scattering sunlit and (partly) shadowed pixels. The complexity of scene demands general spectral mixture model that can adapt to different scenarios surface. this article, we propose physics-based model, i.e., extended shadow multilinear mixing (ESMLM) accounts for typical presence shadows non...