Results 1  10
of
349
Plenoptic Modeling: An ImageBased Rendering System
, 1995
"... Imagebased rendering is a powerful new approach for generating realtime photorealistic computer graphics. It can provide convincing animations without an explicit geometric representation. We use the “plenoptic function” of Adelson and Bergen to provide a concise problem statement for imagebased ..."
Abstract

Cited by 771 (23 self)
 Add to MetaCart
Imagebased rendering is a powerful new approach for generating realtime photorealistic computer graphics. It can provide convincing animations without an explicit geometric representation. We use the “plenoptic function” of Adelson and Bergen to provide a concise problem statement for imagebased rendering paradigms, such as morphing and view interpolation. The plenoptic function is a parameterized function for describing everything that is visible from a given point in space. We present an imagebased rendering system based on sampling, reconstructing, and resampling the plenoptic function. In addition, we introduce a novel visible surface algorithm and a geometric invariant for cylindrical projections that is equivalent to the epipolar constraint defined for planar projections.
QuickTime VR  An ImageBased Approach to Virtual Environment Navigation
, 1995
"... Traditionally, virtual reality systems use 3D computer graphics to model and render virtual environments in realtime. This approach usually requires laborious modeling and expensive special purpose rendering hardware. The rendering quality and scene complexity are often limited because of the real ..."
Abstract

Cited by 532 (0 self)
 Add to MetaCart
Traditionally, virtual reality systems use 3D computer graphics to model and render virtual environments in realtime. This approach usually requires laborious modeling and expensive special purpose rendering hardware. The rendering quality and scene complexity are often limited because of the realtime constraint. This paper presents a new approach which uses 360degree cylindrical panoramic images to compose a virtual environment. The panoramic image is digitally warped onthefly to simulate camera panning and zooming. The panoramic images can be created with computer rendering, specialized panoramic cameras or by "stitching" together overlapping photographs taken with a regular camera. Walking in a space is currently accomplished by "hopping" to different panoramic points. The imagebased approach has been used in the commercial product QuickTime VR, a virtual reality extension to Apple Computer's QuickTime digital multimedia framework. The paper describes the architecture, the fil...
Synthesizing Natural Textures
 In ACM Symposium on Interactive 3D Graphics
"... We present a simple texture synthesis algorithm that is wellsuited for a specific class of naturally occurring textures. This class includes quasirepeating patterns consisting of small objects of familiar but irregular size, such as flower fields, pebbles, forest undergrowth, bushes and tree branc ..."
Abstract

Cited by 315 (0 self)
 Add to MetaCart
(Show Context)
We present a simple texture synthesis algorithm that is wellsuited for a specific class of naturally occurring textures. This class includes quasirepeating patterns consisting of small objects of familiar but irregular size, such as flower fields, pebbles, forest undergrowth, bushes and tree branches. The algorithm starts from a sample image and generates a new image of arbitrary size the appearance of which is similar to that of the original image. This new image does not change the basic spatial frequencies the original image; instead it creates an image that is a visually similar, and is of a size set by the user. This method is fast and its implementation is straightforward. We extend the algorithm to allow direct user input for interactive control over the texture synthesis process. This allows the user to indicate largescale properties of the texture appearance using a standard paintingstyle interface, and to choose among various candidate textures the algorithm can create by performing different number of iterations.
Pyramidal parametrics
 Computer Graphics (SIGGRAPH ’83 Proceedings
, 1983
"... The mapping of images onto surfaces may substantially increase the realism and information content of computergenerated imagery. The projection of a flat source image onto a curved surface may involve sampling difficulties, however, which are compounded as the view of the surface changes. As the pr ..."
Abstract

Cited by 307 (1 self)
 Add to MetaCart
The mapping of images onto surfaces may substantially increase the realism and information content of computergenerated imagery. The projection of a flat source image onto a curved surface may involve sampling difficulties, however, which are compounded as the view of the surface changes. As the projected scale of the surface increases, interpolation between the original samples of the source image is necessary; as the scale is reduced, approximation of multiple samples in the source is required. Thus a constantly changing sampling window of viewdependent shape must traverse the source image. To reduce the computation implied by these requirements, a set of prefiltered source images may be created. This approach can be applied to particular advantage in animation, where a large number of frames using the same source image must be generated. This paper advances a "pyramidal parametric " prefiltering and sampling geometry which minimizes aliasing effects and assures continuity within and between target images. Although the mapping of texture onto surfaces is an excellent example of the process and provided the original motivation for its development, pyramidal parametric data structures admit of wider application. The aliasing of not only surface texture, but also highlights and even the surface representations themselves, may be minimized by pyramidal parametric means.
RENDERING FUR WITH THREE DIMENSIONAL TEXTURES
, 1989
"... We present a method for rendering scenes with fine detail via an object called a texel, a rendering primitive inspired by volume densities mixed with anisotropic lighting models. This technique solves a long outstanding problem in image synthesis: the rendering of furry surfaces. ..."
Abstract

Cited by 264 (0 self)
 Add to MetaCart
We present a method for rendering scenes with fine detail via an object called a texel, a rendering primitive inspired by volume densities mixed with anisotropic lighting models. This technique solves a long outstanding problem in image synthesis: the rendering of furry surfaces.
An Efficient Representation for Irradiance Environment Maps
, 2001
"... We consider the rendering of diffuse objects under distant illumination, as specified by an environment map. Using an analytic expression for the irradiance in terms of spherical harmonic coefficients of the lighting, we show that one needs to compute and use only 9 coefficients, corresponding to th ..."
Abstract

Cited by 215 (10 self)
 Add to MetaCart
(Show Context)
We consider the rendering of diffuse objects under distant illumination, as specified by an environment map. Using an analytic expression for the irradiance in terms of spherical harmonic coefficients of the lighting, we show that one needs to compute and use only 9 coefficients, corresponding to the lowestfrequency modes of the illumination, in order to achieve average errors of only 1%. In other words, the irradiance is insensitive to high frequencies in the lighting, and is well approximated using only 9 parameters. In fact, we show that the irradiance can be procedurally represented simply as a quadratic polynomial in the cartesian components of the surface normal, and give explicit formulae. These observations lead to a simple and efficient procedural rendering algorithm amenable to hardware implementation, a prefiltering method up to three orders of magnitude faster than previous techniques, and new representations for lighting design and imagebased rendering.
An ImageBased Approach to ThreeDimensional Computer Graphics
, 1997
"... The conventional approach to threedimensional computer graphics produces images from geometric scene descriptions by simulating the interaction of light with matter. My research explores an alternative approach that replaces the geometric scene description with perspective images and replaces the s ..."
Abstract

Cited by 206 (6 self)
 Add to MetaCart
The conventional approach to threedimensional computer graphics produces images from geometric scene descriptions by simulating the interaction of light with matter. My research explores an alternative approach that replaces the geometric scene description with perspective images and replaces the simulation process with data interpolation. I derive an imagewarping equation that maps the visible points in a reference image to their correct positions in any desired view. This mapping from reference image to desired image is determined by the centerofprojection and pinholecamera model of the two images and by a generalized disparity value associated with each point in the reference image. This generalized disparity value, which represents the structure of the scene, can be determined from point correspondences between multiple reference images. The imagewarping equation alone is insufficient to synthesize desired images because multiple referenceimage points may map to a single point. I derive a new visibility algorithm that determines a drawing order for the image warp. This algorithm results in correct visibility for the desired image independent of the reference image’s contents. The utility of the imagebased approach can be enhanced with a more general pinholecamera
Fundamentals of Texture Mapping and Image Warping
, 1989
"... The applications of texture mapping in computer graphics and image distortion (warping) in image processing share a core of fundamental techniques. We explore two of these techniques, the twodimensional geometric mappings that arise in the parameterization and projection of textures onto surfaces, a ..."
Abstract

Cited by 203 (0 self)
 Add to MetaCart
(Show Context)
The applications of texture mapping in computer graphics and image distortion (warping) in image processing share a core of fundamental techniques. We explore two of these techniques, the twodimensional geometric mappings that arise in the parameterization and projection of textures onto surfaces, and the filters necessary to eliminate aliasing when an image is resampled during texture mapping or warping. With respect to mappings, this work presents a tutorial on three common classes of mapping: the affine, bilinear, and projective. For resampling, this work develops a new theory describing the ideal, space variant antialiasing filter for signals warped and resampled according to an arbitrary mapping. Efficient implementations of the mapping and filtering techniques are discussed and demonstrated.
Interactive Texture Mapping
, 1993
"... This paper describes a new approach to texture mapping. A global method to lower the distortion of the mapped image is presented; by considering a general optimization function we view the mapping as an energyminimization process. We have constructed an interactive texture tool, which is fast and e ..."
Abstract

Cited by 157 (2 self)
 Add to MetaCart
This paper describes a new approach to texture mapping. A global method to lower the distortion of the mapped image is presented; by considering a general optimization function we view the mapping as an energyminimization process. We have constructed an interactive texture tool, which is fast and easy to use, to manipulate atlases in texture space. We present the tool’s large set of interactive operations on mapping functions. We also introduce an algorithm which automatically generates an atlas for any type of object. These techniques allow the mapping of different textures onto the same object and handle noncontinuous mapping functions, needed for complicated mapped objects.