In computer vision for object recognition or navigation, shadows are a frequent occurrence. However, shadows are difficult to recognize because they cannot be infallibly recognized until a scene's geometry and lighting are known. We present a number of cues which together strongly suggest the identification of a shadow and which can be examined without a high computational cost. The techniques ...

To prevent moving shadows being misclassified as moving objects or parts of moving objects, this paper presents an explicit method for detection of moving cast shadows on a dominating scene background. Those shadows are generated by objects moving between a light source and the background. Moving cast shadows cause a frame difference between two succeeding images of a monocular video image sequ...

Our body-shadows are special stimuli in the visual world. They often have anatomical resemblance with our own body-parts and move as our body moves, with spatio-temporal correlation. Here, we show that self-attributed body-shadows cue attention to the body-part they refer to, rather than the location they occupy. Using speeded spatial discrimination for tactile or visual targets at the hands, o...

Shadows appear in remote sensing images due to elevated objects. Shadows cause hindrance to correct feature extraction of image features like buildings ,towers etc. in urban areas it may also cause false color tone and shape distortion of objects, which degrades the quality of images. Hence, it is important to segment shadow regions and restore their information for image interpretation. This p...

A novel verifiable secret sharing method for Verifiable secret sharing (VSS) in halftone image based on linear block code with a parity check matrix is proposed. The proposed method, which not only verifies a secret image but also introduces multiple shadows for multiple users. The proposed method adopts forward error correction code (FEC) strategy based on property of linear block codes. There...

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 ...

We introduce invariants of 2-component fronts similar to Arnold's 1] invariants J following approach of Viro 22] and generalize Viro's formulas to invariants of 1 and 2-component 0-homologous fronts on surfaces of non-zero Euler characteristic. We modify Turaev's construction 19] of link shadows and deene shadows of Legendrian links in ST S 2. This enables us to relate integral formulas for J +...

We present a new method for real-time rendering of shadows in dynamic scenes. Our approach builds on the shadow map algorithm by attaching geometric primitives that we call “smoothies” to the objects’ silhouettes. The smoothies give rise to fake shadows that appear qualitatively like soft shadows, without the cost of densely sampling an area light source. The soft shadow edges hide objectionabl...