For merging real and virtual worlds, the following three aspects have to be taken into account: geometry, illumination and time. In this paper we propose the framework to project shadow of real objects on virtual world for seamless mixed reality environment. We have also developed the system such that ser in IPT illuminate virtual and real world with virtual light, shadow of real objects is pro...

When an extended light source such as the Sun illuminates two objects so that their shadows lie close to each other, the shadow of one of the objects occasionally appears to bulge out toward the shadow of the other. This effect is caused by the overlap of the penumbras of the shadows and is analyzed here with ray theory. A laboratory demonstration of this phenomenon is performed and compared wi...

In this paper we present a shadow mapping technique for hemispherical and omnidirectional light sources using dual-paraboloid mapping. In contrast to the traditional perspective projection this parameterization has the benefit that only a minimal number of rendering passes is needed during generation of the shadow maps, making the method suitable for dynamic environments and real time applicati...

In this paper, we have proposed an efficient moving cast shadow detection using texture features. Texture features are estimated using fractal dimension and is employed to discriminate between shadow region and moving foreground region. Complexity and noise reduction is achieved using wavelet transform which has not been performed before in the literature. Block-wise calculation has accelerated...

We prove the existence of a new class of solutions, called shadow kinks, of the Painleve II equation d 2w dz2 = 2w3 + zw + α, where α < 0 is a constant. Shadow kinks are sign changing solutions which satisfyw(z) ∼ −√−z/2 as z → −∞ and w(z) ∼ −z as z → ∞.These solutions play a critical role in the prediction of a new class of topological defects, one dimensional shadow kinks and two dimensional ...

Moser’s shadow problem asks to estimate the shadow function sb(n) giving the minimal value with the property that for each bounded convex polyhedron P in 3-space with n vertices there is some direction v (depending on P ) such that when illuminated by parallel light rays from infinity in direction v the polyhedron casts a shadow having at least sb(n) vertices. A general version of the problem a...

We present a practical and inexpensive method for creating physical objects that cast different color shadow images when illuminated by prescribed lighting configurations. The input to our system is a number of lighting configurations and corresponding desired shadow images. Our approach computes attenuation masks, which are then printed on transparent materials and stacked to form a single mul...

This paper attempts to create coloured semi-transparent shadow images that can be projected onto multiple screens simultaneously from different viewpoints. The inputs to this approach are a set of coloured shadow images and view angles, projection information and light configurations for the final projections. We propose a method to convert coloured semi-transparent shadow images to a 3D visual...