Issue 2

Permanent URI for this collection


PRIP - A Parallel Raster Image Processor

Van Campenhout, Jan M.
Lasure, Roeland

Pictorial Editing by Shape Matching Techniques

Ventura, A. Della
Ongaro, P.
Schettini, R.

A New Approach for the Generation of Circles

Hsu, S. Y.
Chow, Louis R.
Liu, H. C.

The Potential Equation and Importance in Illumination Computations

Pattanaik, S. N.
Mudur, S. P.

A Survey of 3D Solid Reconstruction from 2D Projection Line Drawings

Wang, Weidong
Grinstein, Georges G.

The ARGOSI Classification Scheme for Graphics and Networking Applications

Sutcliffe, D.C.
Gallop, J.R.
Maybury, R.
Day, R.A.
Duce?, D.A.
Reynolds?, G.J.

A Note on 3D-Clip Optimisation

Hubl, Josef


BibTeX (Issue 2)
                
@article{
10.1111:1467-8659.1220095,
journal = {Computer Graphics Forum}, title = {{
PRIP - A Parallel Raster Image Processor}},
author = {
Van Campenhout, Jan M.
and
Lasure, Roeland
}, year = {
1993},
publisher = {
Blackwell Science Ltd and the Eurographics Association},
ISSN = {1467-8659},
DOI = {
10.1111/1467-8659.1220095}
}
                
@article{
10.1111:1467-8659.1220111,
journal = {Computer Graphics Forum}, title = {{
Pictorial Editing by Shape Matching Techniques}},
author = {
Ventura, A. Della
and
Ongaro, P.
and
Schettini, R.
}, year = {
1993},
publisher = {
Blackwell Science Ltd and the Eurographics Association},
ISSN = {1467-8659},
DOI = {
10.1111/1467-8659.1220111}
}
                
@article{
10.1111:1467-8659.1220105,
journal = {Computer Graphics Forum}, title = {{
A New Approach for the Generation of Circles}},
author = {
Hsu, S. Y.
and
Chow, Louis R.
and
Liu, H. C.
}, year = {
1993},
publisher = {
Blackwell Science Ltd and the Eurographics Association},
ISSN = {1467-8659},
DOI = {
10.1111/1467-8659.1220105}
}
                
@article{
10.1111:1467-8659.1220131,
journal = {Computer Graphics Forum}, title = {{
The Potential Equation and Importance in Illumination Computations}},
author = {
Pattanaik, S. N.
and
Mudur, S. P.
}, year = {
1993},
publisher = {
Blackwell Science Ltd and the Eurographics Association},
ISSN = {1467-8659},
DOI = {
10.1111/1467-8659.1220131}
}
                
@article{
10.1111:1467-8659.1220137,
journal = {Computer Graphics Forum}, title = {{
A Survey of 3D Solid Reconstruction from 2D Projection Line Drawings}},
author = {
Wang, Weidong
and
Grinstein, Georges G.
}, year = {
1993},
publisher = {
Blackwell Science Ltd and the Eurographics Association},
ISSN = {1467-8659},
DOI = {
10.1111/1467-8659.1220137}
}
                
@article{
10.1111:1467-8659.1220123,
journal = {Computer Graphics Forum}, title = {{
The ARGOSI Classification Scheme for Graphics and Networking Applications}},
author = {
Sutcliffe, D.C.
and
Gallop, J.R.
and
Maybury, R.
and
Day, R.A.
and
Duce?, D.A.
and
Reynolds?, G.J.
}, year = {
1993},
publisher = {
Blackwell Science Ltd and the Eurographics Association},
ISSN = {1467-8659},
DOI = {
10.1111/1467-8659.1220123}
}
                
@article{
10.1111:1467-8659.1220159,
journal = {Computer Graphics Forum}, title = {{
A Note on 3D-Clip Optimisation}},
author = {
Hubl, Josef
}, year = {
1993},
publisher = {
Blackwell Science Ltd and the Eurographics Association},
ISSN = {1467-8659},
DOI = {
10.1111/1467-8659.1220159}
}

Browse

Recent Submissions

Now showing 1 - 7 of 7
  • Item
    PRIP - A Parallel Raster Image Processor
    (Blackwell Science Ltd and the Eurographics Association, 1993) Van Campenhout, Jan M.; Lasure, Roeland
    Like colour video displays and laser printers, laser photoplotters are raster scan devices. For such devices, the pixel stream representing the image must be generated in real time, and in the (scan line) order required. However, the typical size of the images photoplotters produce is an order of magnitude higher than that of video displays and laser printers, precluding the use of full-size bitmap memories. These requirements pose particular implementation problems for the raster image processor generating the pixel stream.The parallel RIP system presented here is aimed at high-resolution laser photoplotters, and features a largely scalable performance ranging from 40 to several hundred megapixels per second. It is built with standard components such as graphics microprocessors and VRAM memories. Its architecture is that of a distributed memory multiprocessor system with a global ring-like topology. And most importantly, it can be programmed using the traditional sequential programming paradigm. Only minor additions are needed to sequential graphical algorithms to be executable on the system with an arbitrary number of processors.A prototype 8-processor PRIP system has been built and tested generating printed circuit board images for a direct imaging photoplotter. The prototype exhibits a near-linear speedup with respect to a monoprocessor solution. Architectural simulations indicate that the system can be expanded to well over 10 processors.
  • Item
    Pictorial Editing by Shape Matching Techniques
    (Blackwell Science Ltd and the Eurographics Association, 1993) Ventura, A. Della; Ongaro, P.; Schettini, R.
    A number ofpainting and retouching packages operate much like the artist s traditional canvas andpalette, with electronic toolsfunctioning like their studio counterparts. These programs, while offering an ample set of tools for creating an image, suffer from an intrinsic limitation as regards its modification, which lies in the fact that changes to the shape of objects and those requiring some kind ofpattern recognition are generally difficult and cannot be accomplished automatically. This paper deals with an original methodfor providing a pictorial editor with the"search-and-replace" facility, that works rather like text substitution in a word processor. The user defines the search (model) and the replacement (target) patterns by example, i.e. by showing the system the patterns taken from the image or an existing catalogue. The editor then searchesfor objects that match the model s pattern and replaces them with the target one in an automatic or user-controlled mode. The method is based on a model-driven matching technique, capable of measuring the similarity of objects that are partially occluded or transformed by translation, rotation, or change of scale. Salient features of the method are its robustness and the limited number of parameters needed to adapt the search procedure to different application contexts. A search-and-replace function used for pattern-editing in the field of textile design, is presented as a working example.
  • Item
    A New Approach for the Generation of Circles
    (Blackwell Science Ltd and the Eurographics Association, 1993) Hsu, S. Y.; Chow, Louis R.; Liu, H. C.
    Two incremental algorithms for drawing circles using short line segments are proposed in this paper. The proposed algorithms can draw manypoints at one time. They use only addition, subtraction, and shift operations except in the initialization of the algorithm. Using this simplified approach we can greatly increase the speed of drawing circles, relative to other conventional algorithms.
  • Item
    The Potential Equation and Importance in Illumination Computations
    (Blackwell Science Ltd and the Eurographics Association, 1993) Pattanaik, S. N.; Mudur, S. P.
    An equation adjoint to the luminance equation for describing the global illumination can be formulated using the notion of a surface potential to illuminate the region of interest. This adjoint equation which we shall call as the potential equation, is fundamental to the adjoint radiosity equation used to devise the importance driven radiosity algorithm. In this paper we first briefly derive the adjoint system of integral equations and then show that the adjoint linear equations used in the above algorithm are basically discrete formulations of the same. We also show that the importance entity of the linear equations is basically the potential function integrated over a patch. Further we prove that the linear operators in the two equations are indeed transposes of each other.
  • Item
    A Survey of 3D Solid Reconstruction from 2D Projection Line Drawings
    (Blackwell Science Ltd and the Eurographics Association, 1993) Wang, Weidong; Grinstein, Georges G.
    The reconstruction of a 3D object from its 2D projection(s) and its corresponding problem of 3D object recognition are two of the important research areas in the field of computer vision and artificial intelligence. Reconstruction involves determining the geometric and topological relationship of an object s atomic parts whereas recognition involves identifying an object by some form of template matching. Nagendra and Gujar1 gave a survey of several papers on reconstruction of 3D object from its 2D views. In this paper we present a taxonomy of 3D object reconstruction from 2D projection line drawings. We base the classification on the number of 2D views of the 3D solid object, the degree of user interaction necessary for correct reconstruction, and the internal representation used in the reconstruction process. We discuss the basic issues associated with this problem, review the relevant literature and present topics for future research.
  • Item
    The ARGOSI Classification Scheme for Graphics and Networking Applications
    (Blackwell Science Ltd and the Eurographics Association, 1993) Sutcliffe, D.C.; Gallop, J.R.; Maybury, R.; Day, R.A.; Duce?, D.A.; Reynolds?, G.J.
    ARGOSI is a project concerned with the relationship between standards for graphics and networking, as rejected in its full title: Applications Related Graphics and OSI Standards Integration. It is a collaborative project between eleven European organizations and is funded under the Esprit-Il programme of the Commission of the European Community.In order to achieve integration of graphics and OSI standards and to meet the requirements of applications, it is necessary to understand the needs of applications to transfer graphical information and the networking services required to support this. A major part of the ARGOSI project has been to derive a classification framework for applications based on a set of metrics describing their use of graphics and networking. Once classified, a study is to be made to determine the set of graphics and OSI standards that will satisfy the requirements of each group of applications or to identify deficiencies or omissions in the set of current standards that prevent the requirements being met. The classification scheme is believed to be a major stepforward in the field.
  • Item
    A Note on 3D-Clip Optimisation
    (Blackwell Science Ltd and the Eurographics Association, 1993) Hubl, Josef
    In order to optimize the transformation-clipping-pipeline of PHIGS or GKS-3D it is sometimes necessary to determine whether a plane intersects a perpendicular volume or not. The solution to this problem is not very complicated. This paper offers a more effective procedure that handles this task.