In Photometric stereo, the existence of specularities hampers to recover the normal map. To deal with this common reflective phenomenon, we introduce a novel representation for specular reflection with a set of specular basis functions with different roughness values. This representation is suitable for any intensively or weakly specular object, and is introduced into the photometric stereo alg...

We present a novel image-based method for separating diffuse and specular reflections of real objects under distant environmental illumination. By illuminating a scene with only four high frequency illumination patterns, the specular and diffuse reflections can be separated by computing the maximum and minimum observed pixel values. Furthermore, we show that our method can be extended to separa...

Many flat panel displays (FPDs) have anti-reflection surface treatments that differ in character from those of traditional cathode-ray-tube displays. Specular reflection models (mirror-like, producing a distinct image) combined with diffuse (Lambertian) reflection models can be entirely inadequate to characterize the reflection properties of such displays. A third reflection component, called h...

In this paper we present a new method for the identification of specular reflectance in colour images. We have developed a bi-dimensional histogram which allows the exploitation of the relations between the signals of intensity and saturation of a colour image. Once the diagram has been constructed, it is possible to verify that the pixels of the specular reflectance are located in a well-defin...

We obtain valuable information on the angular and seasonal variability of surface reflectance using a hand-held spectrometer from a light aircraft. The data is used to test a procedure that allows us to estimate visible surface reflectance from the longer wavelength 2.1 _tm channel (mid-IR). Estimating or avoiding surface reflectance in the visible is a vital first step in most algorithms that ...

We have synthesized ordered carbon nanotube (CNT) arrays in porous anodic alumina (PAA) matrix, and have characterized their total optical reflectance and bi-directional reflectance distribution function after each processing step of the microwave plasma chemical vapor deposition process (MPCVD). For a PAA sample without CNT growth, the reflectance shows an oscillating pattern with wavelength t...

While subsurface scattering is common in many real objects, almost all separation algorithms focus on extracting specular and diffuse components from real images. In this paper, we propose an appearance-based approach to separate non-directional subsurface scattering reflectance from photometric images, in addition to the separation of the off-specular and non-Lambertian diffuse components. Our...