62 results about "Cast shadow" patented technology

An apparatus and method for real-time volume processing and universal three-dimensional rendering. The apparatus includes a plurality of three-dimensional (3D) memory units; at least one pixel bus for providing global horizontal communication; a plurality of rendering pipelines; at least one geometry bus; and a control unit. The apparatus includes a block processor having a circular ray integration pipeline for processing voxel data and ray data. Rays are generally processed in image order thus permitting great flexibility (e.g., perspective projection, global illumination). The block processor includes a splatting unit and a scattering unit. A method for casting shadows and performing global illumination in relation to light sources includes sweeping a two dimensional array of rays through the volume can also be implemented with the apparatus. A method for approximating a perspective projection includes using parallel projection.

A method, computer program product and system for rendering soft shadows in an image or frame representing a 3D scene, comprising the steps, from a light's point of view, of detecting and creating a list of edges casting shadows, a list of soft shadow edges and a list of shadow volumes polygons; rendering said soft shadow edges into one or more sides of a cubemap, rendering said shadow volume polygons in combination with a stencil buffer to detect full shadowed areas; from a viewer's point of view rendering said scene with said cubemap applied while performing a stencil test operation for preventing the scene to be drawn in shadowed areas, to produce a soft shadowed image.In addition, the system supports the re-use of the shadow volumes and cubemap information for more than one frame.

A method models a scene. A video is acquired of the scene, and for each frame of the video, the method updates a set of background models for each pixel; a set of shadow models for each pixel; a set of shadow flow vectors for each color; and a background shadow map. Each pixel in each background model and each shadow model is represented by multiple layers. Each layer includes Gaussian distributions and each Gaussian distribution includes a mean and a covariance. The covariance is an inverse Wishart distribution and the updating is according to a recursive Bayesian estimation process.

An intraoral illumination apparatus is disclosed. The intraoral illumination apparatus of the present invention includes a pair of holders (1), a plurality of illuminants (7), which are provided in each holder (1), and a link unit (2), which connects the holders (1) to each other. Each N holder (1) has a U-shaped cross-section and is made of harmless synthetic resin. Furthermore, the outer surface of the holder may be coated with latex, rubber, silicone or the like, which is soft and harmless to humans. Several illuminants (7) are provided in each holder (1) at positions adjacent to the oral cavity. LEDs (light emitting diodes) or other various well-known illuminants may be used as the illuminants (7). The present invention can illuminate the oral cavity or larynx of a patient without casting shadows and prevent a dark unlit spot from being created in the oral cavity or larynx, thus facilitating medial examination and treatment.

During pre-processing, a 3D model of the object is rendered for various poses by arranging virtual point light sources around the lens of a virtual camera. The shadows are used to obtain oriented depth edges of the object illuminated from multiple directions. The oriented depth edges are stored in a database. A camera acquires images of the scene by casting shadows onto the scene from different directions. The scene can include one or more objects arranged in arbitrary poses with respect to each other. The poses of the objects are determined by comparing the oriented depth edges obtained from the acquired images to the oriented depth edges stored in the database. The comparing evaluates, at each pixel, a cost function based on chamfer matching, which can be speed up using downhill simplex optimization.

A lamp assembly adapted to cast shadow-free illumination over an area. Typically, a lamp assembly includes a plurality of light modules that are disposed in a spaced apart relationship over an area. Desirably, the lamp assembly is arranged to aim the light output of each module for overlapping summation on a target footprint. Modules generally each include a LED light source, a parabolic reflecting mirror arranged to direct light from the LED, a TIR collimating lens disposed at a distal end of the mirror, and a stray light tube disposed between the LED and a dispersing lens element.

An apparatus and method for depicting one or more objects are provided. The method includes determining a geolocation of one or more objects, determining a vector from the objects to a light source, applying shading to the objects according to the vector, determining shadows cast by the objects according to the vector, and depicting the objects in the geolocation with one or more of the applied shading and the cast shadows.

Method and apparatus for counting vehicles at entrances, exits and transition zones of multi-story carparks, including particularly where the ceiling heights can be just marginally higher than the tallest expected vehicle, with a view to determine the carpark occupancy at different carpark levels by counting passing vehicles using a vision-based car counting system without relying on viewing test patterns or employing a blocking beam scheme and yet tolerating vehicles transgressing partially or fully into the wrong lane of a two-lane two-way road while ignoring vehicles moving opposite to the expected direction. Without imposing additional constraints to ambient carpark illumination, the methodology copes with highly specular vehicle surfaces, ignores non-vehicular objects and detects moving cast shadow or highlight, and adapts to daily and seasonal scene changes, and yet estimates vehicle speed.

The image processing device performs processing on a shadow in an image of an object, and includes: an image information obtaining unit obtaining information about an image of the object, the information including luminance information about luminance of light from the object and polarization information about polarization of the light from the object; a shadow area extracting unit extracting an attached shadow area and a cast shadow area from the image of the object based on the luminance information and the polarization information, the attached shadow area appearing on the surface of the object depending on an angle of incidence light, and the cast shadow area appearing on the surface of a material body other than the object when the light is blocked by the object; and an output unit outputting information identifying the attached shadow area and cast shadow area.

The normal vector information generating device generates normal vector information on the surface of an object, and includes: an image information obtaining unit obtaining information about an image of the object, the information including luminance information about luminance of light from the object and polarization information about polarization of the light; a shadow area extracting unit extracting an attached shadow area and a cast shadow area from the image based on the luminance information and the polarization information, the attached shadow area appearing on the surface of the object depending on an angle of incidence light, and the cast shadow area appearing on the surface of a material body when the light is blocked by the object; and a normal vector information generating unit generating normal vector information identifying a normal vector on the surface of the object in the attached shadow area using the polarization information.

Shadow is an inseparable aspect of all natural scenes. When there are multiple light sources or multiple reflections several different shadows may overlap at the same location and create complicated patterns. Shadows are a potentially good source of information about a scene if the shadow regions can be properly identified and segmented. However, shadow region identification and segmentation is a difficult task and improperly identified shadows often interfere with machine vision tasks like object recognition and tracking. A shadow separation and contrast enhancement method based on the polarization of light is provided. Polarization information of scenes is captured by a polarization-sensitive camera and the scenes are processed to effectively separate shadows from different light sources.

A method, apparatus, and article of manufacture are configured to cast a shadow for a two-dimensional vector geometry. A two-dimensional computer-generated rendering comprised of vector geometry is obtained. A face of the vector geometry is then selected and a virtual height is assigned to the face. Once a location of a virtual light source is defined, a shadow for the vector geometry is created and displayed based on the virtual height of the face and the location of the virtual light source.

The invention discloses a method and a device for detecting moving vehicles on the basis of multi-frame differences and cast shadow removal, and relates to the field of intelligent traffic management and video monitoring. The method includes a, acquiring a sequence picture of a current frame; b, acquiring a gray value sequence picture of the current frame; c, acquiring characteristics of binary images of edges of the current frame and edges of interframe differences; d, acquiring edge characteristics of moving vehicles of the current frame; e, acquiring edge characteristics of shadow of the current frame; f, acquiring accurate edge characteristics of the shadow of the current frame; g, acquiring an accurate picture sequence of the edge characteristics of the moving vehicles; and h, extracting specific coordinates of the moving vehicles from the picture sequence. The method and the device have the advantages that a capture scheme on the basis of video detection is provided for an intelligent traffic system to detect the moving vehicles, the system is simple in installation and easy to maintain, moving vehicle capture rate is increased, and motor vehicle position detection precision is improved.