A new general reflectance model for computer graphics is presented.The model is based on physical optics and describes specular, di-rectional diffuse, and uniform diffuse reflection by a surface. Thereflected light pattern depends on wavelength, incidence angle, twosurface roughness parameters. and surface refractive index. The for-mulation is self consistent in terms of...

The recovery of objects obscured by scattering is an important goal in imaging and has been approached by exploiting, for example, coherence properties, ballistic photons or penetrating wavelengths. Common methods use scattered light transmitted through an occluding material, although these fail if the occluder is opaque. Light is scattered not only by transmission through objects, but also by ...

We present an image-based method for separating diffuse and specular reflections using environmental structured illumination. Two types of structured illumination are discussed: phase-shifted sine wave patterns, and phaseshifted binary stripe patterns. In both cases the low-pass filtering nature of diffuse reflections is utilized to separate the reflection components. We illustrate our method o...

In this paper, we present a method to recover the parameters governing the reflection of light from a surface making use of a single hyperspectral image. To do this, we view the image radiance as a combination of specular and diffuse reflection components and present a cost functional which can be used for purposes of iterative least squares optimisation. This optimisation process is quite gene...

We consider a globally hyperbolic, stationary spacetime containing a black hole but no white hole. We assume, further, that the event horizon, N , of the black hole is a Killing horizon with compact cross-sections. We prove that if surface gravity is non-zero constant throughout the horizon one can globally extend such a spacetime so that the image of N is a proper subset of a regular bifurcate...

For synthesizing realistic images of a real three dimensional object, reflectance properties of the object surface, as well as the object shape, need to be measured. This paper describes one approach to create a three dimensional object model with physically correct reflectance properties by observing a real object. The approach consists of three steps. First, a sequence of range images and col...

High-resolution time-of-flight phonon-reflection spectra in sapphire crystals are analyzed with the aid of detailed numerical calculations. It is argued that spectra from vacuum interfaces may be understood if about half the incident phonons are assumed to be reflected specularly, the remainder diffusely. A simple model of the effect on spectra of diffuse scattering is presented and compared to...