We introduce a variational method for multi-view shapefrom-shading under natural illumination. The key idea is to couple PDE-based solutions for single-image based shapefrom-shading problems across multiple images and multiple color channels by means of a variational formulation. Rather than alternatingly solving the individual SFS problems and optimizing the consistency across images and chann...

Direct volume rendering is a commonly used technique in visualization applications. Many of these applications require sophisticated shading models to capture subtle lighting effects and characteristics of volumetric data and materials. For many volumes, homogeneous regions pose problems for typical gradient based surface shading. Many common objects and natural phenomena exhibit visual quality...

Shading and classification are among the most powerful and important techniques used in volume rendering. Unfortunately, for hardware accelerated volume rendering based on OpenGL, direct classification was previously only supported on SGI platforms and shading could only be approximated inaccurately, resulting in artifacts mostly visible in darkening. In this paper, we present a novel approach ...

In this paper, a method for estimating parameters of a 3-D shape from a 2-D shading image using a genetic algorithms (GAs) is proposed. The shape of the object is represented by a superquadrics model, and then the model parameters are coded for being applied to GAs. The coded string is evaluated according to the similarity of the shading image calculated from the 3D model shape represented by t...

Much of the variation in soybean yield is associated with changes in pod number per plant, however physiological regulation of pod number is not well understood. Three determinate soybean cultivars, Hai339 (H339), Heinong35 (HN35) and Kennong18 (KN18) were grown for 2 years at 27 plants m in a field experiment and exposed to shading and light enrichment. The data of total soluble sugar (TSS) in...

This study presents a contribution to the characterization of occupants’ behavior regarding the manual control of electric lighting in combination with shading control in offices. The procedure and monitoring results for eight single-occupied office spaces is described. The analysis of the collected data indicated that occupants kept electric lighting On during most of the monitoring period and...

PURPOSE The aim of this study was to improve the image quality of cone-beam computed tomography (CBCT) mounted on the gantry of a linear accelerator used in radiation therapy based on the image information provided by planning multi-detector CT (MDCT). METHODS MDCT-based shading correction for CBCT and virtual monochromatic CT (VMCT) synthesized using the dual-energy method were performed. In...

To evaluate the population variation, individual plasticity, and local adaptability of Solidago canadensis in response to shade treatment, we conducted a common pots experiment with a total of 150 ramets (5 genets, 15 populations, and 2 treatments) subjected to both control (natural light) and shady treatment (10% of natural light). Shade treatment significantly reduced growth and content of de...

We present a method for generating art-directable volumetric effects, ranging from physically-accurate to non-physical results. Our system mimics the way experienced artists think about volumetric effects by using an intuitive lighting primitive, and decoupling the modeling and shading of this primitive. To accomplish this, we generalize the physically-based photon beams method to allow arbitra...

It is a well-documented fact that partial shading of a photovoltaic array reduces it output power capability. However, the relative amount of such degradation in energy production cannot be determined in a straight forward manner, as it is often not proportional to the shaded area. This paper clarifies the mechanism of partial PV shading on a number of PV cells connected in series and/or parall...