Received: 15 August 2005 Revised: 21 December 2005 Accepted: 6 January 2006 Online publication date: 10 April 2006 Abstract Very early in the object recognition process the human visual system extracts shading information. While shading can enhance the visibility of structures, it can have a negative impact on the judgment of sizes of elements in a structure. In certain visualization systems th...

We propose decoupled sampling, an approach that decouples shading from visibility sampling in order to enable motion blur and depth-of-field at reduced cost. More generally, it enables extensions of modern real-time graphics pipelines that provide controllable shading rates to trade off quality for performance. It can be thought of as a generalization of GPU-style mul-tisample antialiasing (MSA...

One of the main techniques used by software renderers to produce stunningly realistic images is programmable shading—executing an arbitrarily complex program to compute the color at each pixel. Thus far, programmable shading has only been available on software rendering systems that run on general-purpose computers. Rendering each image can take from minutes to hours. Parallel rendering engines...

CBCT images suffer from acute shading artifacts primarily due to scatter. Numerous image-domain correction algorithms have been proposed in the literature that use patient-specific planning CT images to estimate shading contributions in CBCT images. However, in the context of radiosurgery applications such as gamma knife, planning images are often acquired through MRI which impedes the use of p...

Shading has a great impact to the human perception of 3D objects. Thus, in order to create or to deform a 3D object, it seems natural to manipulate its perceived shading. This paper presents a new solution for the software implementation of this idea. Our approach is based on the ability of a user to coarsely draw a shading, under different lighting directions. With this intuitive process, user...

An understanding of light and its interaction with matter is essential to produce images. As the modeling of light sources, light transport and light re ection improves, it becomes possible to render images with increasing realism. The central motivation behind this thesis is to improve realism in computer graphics images by more accurate local shading models and to assist the user to obtain th...

Previous studies have demonstrated that the perception of shading is based upon assumptions about lighting direction, for example, light from above. However, it is not clear whether these assumptions are used in the perception of cast shadows. Moreover, it is unclear whether a perceptual interaction exists between shading and cast shadows because until now they have been studied separately. In ...

Abstract Stereophotoclinometry (SPC) makes it possible to extract the shapes of surfaces by combining information from images, namely stereo parallax data and surface shading slopes, with knowledge location a spacecraft. This technique has been used extensively in past few decades describe planets small bodies, such as asteroids comets. It also carefully navigate spacecraft around very case OSI...

Light is an important resource for plant growth and development, crops need to change their physiological characteristics to different light environments. Fragaria ananassa Duch. cv. Toyonoka. is an important economic plant which is widely planted at home. A greenhouse experiment was conducted from April 2010 with different sun-shading treatment, 85% (CK), 60% (T1), 35% (T2) and 10% (T3). After...