Starting from Nos. 3 and 4 of this volume, we will also include in these pages the Abstracts of papers published in Machine GRAPHICS & VISION journal.

Machine GRAPHICS & VISION, Vol. 3 (1994), Nos. 1/2:

Special issue:
Proc. 3rd International Conference on Computer Graphics and Image Processing (GKPO'94),
Spala, Poland, May 16-20, 1994.

Stepien C., Kalisiak Z., Gracki K.:
Elastic meshes in dynamic modeling for computer graphics.
MGV vol. 3, nos. 1/2, 1994, pp. 5-22.

Branki N.E., Grabska E.J:
The Coup D'Oeil: a realization scheme for emergent forms in design.
MGV vol. 3, nos. 1/2, 1994, pp. 23-32.

Stepien C., Chabko K.:
The conversion of the data describing the solids in the polygonal form into the mesh form.
MGV vol. 3, nos. 1/2, 1994, pp. 33-42.

Putz B., Ciarski R:
The interactive tool for editing and shape evaluation of bicubic surfaces.
MGV vol. 3, nos. 1/2, 1994, pp. 43-50.

Nagae T., Agui T., Nagahashi H.:
Isosurface construction from volume data.
MGV vol. 3, nos. 1/2, 1994, pp. 51-60.

Pawlak M.:
On digital approximation of moment descriptors.
MGV vol. 3, nos. 1/2, 1994, pp. 61-68.

Denkowska S., Grabska E.J., Marek K.:
Application of Birkhoff's aesthetic measure to computer aided design of vases.
MGV vol. 3, nos. 1/2, 1994, pp. 69-75.

Kulpa Z.:
Diagrammatic representation and reasoning.
MGV vol. 3, nos. 1/2, 1994, pp. 77-103.

Rokita P:
Generation of depth of field effects in virtual reality applications.
MGV vol. 3, nos. 1/2, 1994, pp. 105-110.

Ballo M.:
A new approach to non self-intersecting polygon clipping.
MGV vol. 3, nos. 1/2, 1994, pp. 111-122.

Myszkowski K., Wicynski K., Khodulev A:
Simulation of ideal specular light path by ray tracing.
MGV vol. 3, nos. 1/2, 1994, pp. 123-137.

Wojdala A., Gruszewski M., Dudkiewicz K.:
Using hardware texture mapping for efficient image synthesis and walkthrough with specular effects.
MGV vol. 3, nos. 1/2, 1994, pp. 139-151.

Oksala T.:
Architectural pattern generation: semantic dimensions and pragmatic finals.
MGV vol. 3, nos. 1/2, 1994, pp. 153-160.

Grabska E.J., Grabski W.S., Jablonski M., Skomorowski M.:
Application of neural networks to pattern generation.
MGV vol. 3, nos. 1/2, 1994, pp. 161-170.

Sramek M.:
Cubic macro-regions for fast voxel traversal.
MGV vol. 3, nos. 1/2, 1994, pp. 171-179.

Chrzaszcz W., Stepien C., Chabko K.:
Visualization of mesh modeled objects whose shapes vary in time.
MGV vol. 3, nos. 1/2, 1994, pp. 181-192.

Bruyelle J.-L., Cabestaing F., Le Moal E.:
Video effects by extracting edges of moving objects.
MGV vol. 3, nos. 1/2, 1994, pp. 193-201.

Wcislo R., Dzwinel W., Kitowski J., Moscinski J.:
Real-time animation using molecular dynamics methods.
MGV vol. 3, nos. 1/2, 1994, pp. 203-210.

Chrzaszcz J.R.:
Predicting performance of a graphics subsystem.
MGV vol. 3, nos. 1/2, 1994, pp. 211-218.

Rzeszut J.:
Accurate colour rendering - the comparison of desaturation algorithms.
MGV vol. 3, nos. 1/2, 1994, pp. 219-232.

Newton A.:
A continuous analogue human computer interface, a possible aid to the assimilation of calculated results.
MGV vol. 3, nos. 1/2, 1994, pp. 233-240.

Serba I., Prikryl P.:
Creative graphics in education.
MGV vol. 3, nos. 1/2, 1994, pp. 241-248.

Morawski M.:
On recognition of distorted objects on binary images.
MGV vol. 3, nos. 1/2, 1994, pp. 249-256.

Kulikowski J.L.:
Recognition of patterns in semiordered observation spaces.
MGV vol. 3, nos. 1/2, 1994, pp. 257-262.

Agui T., Terada K., Nagahashi H., Nagao T.:
A technique for 3D object recognition using superquadrics.
MGV vol. 3, nos. 1/2, 1994, pp. 263-273.

Nagao T., Agui T., Nagahashi H.:
2D and 3D object recognition using a genetic algorithm.
MGV vol. 3, nos. 1/2, 1994, pp. 275-286.

Polanski A., Borek A.:
The decomposition of the parameter space for recognition of polygonal shapes.
MGV vol. 3, nos. 1/2, 1994, pp. 287-296.

Kasprzak W.:
Road object tracking in monocular image sequence under egomotion.
MGV vol. 3, nos. 1/2, 1994, pp. 297-308.

Garduno M., Vachon B.:
Range image based obstacle detection during mobile robot motion.
MGV vol. 3, nos. 1/2, 1994, pp. 309-318.

Sair K., Burger P.:
An accurate evaluation of myocardium shape from ultrafast CT images using an active contour model.
MGV vol. 3, nos. 1/2, 1994, pp. 319-328.

Mendonca H., Marques de Sa J.P., Silva Carvalho J.L.:
A computer based system of uterine hysteroscopic images analysis.
MGV vol. 3, nos. 1/2, 1994, pp. 329-338.

Zaremba M.B., Porada E., Skorek A.:
Connectionist processing of images for measurement and control systems.
MGV vol. 3, nos. 1/2, 1994, pp. 339-346.

Starovoitov V.:
Distance transform as clustering tool.
MGV vol. 3, nos. 1/2, 1994, pp. 347-354.

Vannoorenberghe P., Wachowski K., Barsoum B. Postaire J.-G.:
Multilevel thresholding for image segmentation.
MGV vol. 3, nos. 1/2, 1994, pp. 355-362.

Bekkhoucha A., Smolarz A.:
Two methods of contrast enhancement based on edges detection.
MGV vol. 3, nos. 1/2, 1994, pp. 363-372.

Ismaili I.A., Gillies D.F.:
Colour image segmentation using regression analysis in RGB space.
MGV vol. 3, nos. 1/2, 1994, pp. 373-384.

Niedzwiecki M., Suchomski P.:
On a new class of edge-preserving filters for noise rejection from images.
MGV vol. 3, nos. 1/2, 1994, pp. 385-392.

Takahashi H., Agui T., Nagahashi H.:
Designing neural networks using several kinds of activation functions by genetic algorithms.
MGV vol. 3, nos. 1/2, 1994, pp. 393-402.

Balaban I.J.:
An optimal algorithm for finding segments intersections.
MGV vol. 3, nos. 1/2, 1994, pp. 403-410.

Sklodowski M., Cudny W.:
Theory and draft algorithm for the light wavelength stepping method.
MGV vol. 3, nos. 1/2, 1994, pp. 411-420.

Ostrowski T., Woznicki J.:
Suboptimal weighted order statistic filtering using genetic algorithm.
MGV vol. 3, nos. 1/2, 1994, pp. 421-429.

Skarbek W.:
Banach constructor in fractal compression.
MGV vol. 3, nos. 1/2, 1994, pp. 431-441.

Ignasiak K., Skarbek W.:
Tree structures for vector quantization.
MGV vol. 3, nos. 1/2, 1994, pp. 443-449.

Ignasiak K., Lukaszewicz W., Skarbek W.:
Colour quantization methods.
MGV vol. 3, nos. 1/2, 1994, pp. 451-456.

Bedkowski K., Karaszkiewicz W., Mozgawa J., Olenderek H., Piekarski E.:
Some aspects of the use of video imageries in forestry.
MGV vol. 3, nos. 1/2, 1994, pp. 457-461.

Defrocourt S., Fernandez-Maloigne C., Duran M.:
Use of texture descriptors for adaptative coding.
MGV vol. 3, nos. 1/2, 1994, pp. 463-478.

Machine GRAPHICS & VISION, Vol. 3 (1994), No. 3:

Grabska E.:
Theoretical concepts of graphical modeling. Part three: state of the art.
MGV vol. 3, no. 3, 1994, pp. 481-512.

The paper carries out a multilevel analysis of our approach to graphical modeling, and this approach is discussed within the framework of graph transformations and the framework of automated pattern synthesis. On the other hand, some possibilities of using our approach in architecture and computer art are presented.

Gröller E., Löffelmann H.:
Extended camera specification for image synthesis.
MGV vol. 3, no. 3, 1994, pp. 513-530.

Typically a rather simple definition of the viewing parameters (e.g., perspective projection) is used for ray tracing, which is one of the most powerful rendering techniques for generating realistic images. In this paper this simple camera model is extended in several ways to increase user flexibility. A sequence of mappings defines a more general way to assign 3D rays for each pixel of the final raster image. These rays are then taken as primary rays in the following ray tracing step. An extended camera specification, for example, makes possible the projection of the object scene onto more general projection surfaces (quadrics, free form surfaces). Different views of the same object scene may be incorporated within one single image. A test implementation and sample images show the feasibility of the approach. The extended camera specification enables more elaborate viewing techniques which may be used, e.g. for virtual reality, arts and special effects.
Key words: computer graphics, ray tracing, camera specifications.

Ablameyko S., Okun O.:
Text separation from graphics based on compactness and area properties.
MGV vol. 3, no. 3, 1994, pp. 531-541.

Separation of text from graphics is one of the important tasks in document image processing. This task can be solved by many hitherto proposed methods, provided that the processed document satisfies some constraints. Examples of such constraints are: 1) text lines must be exactly horizontal or vertical, i.e. without skew; 2) text and graphics blocks must have a rectangular shape. In practice, these constraints (or at least one of them) can be violated. In this paper, we propose a new algorithm to perform the text/graphics separation for technical paper pages when the above constraints are ignored. Our approach is based on two simple properties of these documents: the area and the compactness property. The separation is performed by considering only the area and the bounding rectangle of connected components. The proposed properties take into account both geometrical and spatial relationships between text and graphics elements. The area property allows to separate the large-sized graphics from other components quickly. The compactness property allows to select the text components when the above constraints are violated.
Key words: bounding rectangle, text/graphics separation, document analysis, connected component.

Chmielewski L., Sklodowski M., Cudny W., Nieniewski M., Kurianski A., Michalski B.:
Fringe image enhancing in the light wavelength stepping method.
MGV vol. 3, no. 3, 1994, pp. 543-578.

Images used for the Light Wavelength Stepping Method (LWSM), obtained in white light and with random dot patterns, are different from typical fringe images because of their `grainy' texture and untypical sparseness of fringes. For these images the traditional fringe-oriented methods of image enhancement which rely on the directional and repetitive structure of an image fail. Hence, three other methods have been adapted and tested: adaptive median filtering, image enhancement based on estimated Markov model, and image enhancement based on weak membrane model. While the results are satisfying for all of them, the smoothing capability of the Markov and membrane methods, the contrast preserving feature of the adaptive median filter, and the edge preserving capability of the membrane method have to be emphasized. A procedure for equalizing and enhancing the contrast of a fringe image has been proposed and evaluated. From the underlying study a conclusion concerning the position of fringes in real images can be drawn.
Key words: fringe images, image enhancing, speckle methods, Light Wave Stepping Method, fringe image equalizing.

Bielecki A., Rog M.:
Aesthetic measure for fractals consisting of line segments.
MGV vol. 3, no. 3, 1994, pp. 579-588.

This article discusses the aesthetic measure of fractal sets consisting of line segments according to the Birkhoff theory. The complexity of fractal set is proposed in the way that it does not converge to infinity. Some examples of the aesthetic measure for a few fractals are calculated as well.
Key words: aesthetic measure, complexity, fractal set.

Rudak B., Szyszkowicz M.:
Self-reference sentences and patterns.
MGV vol. 3, no. 3, 1994, pp. 591-594.

Self-reference sentences in fuzzy logic are realized as iterative processes. The behaviour of such dynamical systems is represented graphically. In this study more attention is given to very and fairly in logical sentences.

Szyszkowicz M.:
Three experiments with chaos.
MGV vol. 3, no. 3, 1994, pp. 595-598.

Examples of three non-standard dynamical systems are presented and illustrated.

Luchowski L.:
Segmentation of images in flat binary scenes in uneven lighting. [Dissertation Abstract]
MGV vol. 3, no. 3, 1994, p. 599.


Machine GRAPHICS & VISION, Vol. 3 (1994), No. 4:

Myszkowski K., Wojdala A., Wicynski K.:
Non-uniform adaptive meshing for global illumination.
MGV vol. 3, no. 4, 1994, pp. 601-609.

This paper presents an efficient adaptive mesh subdivision technique for view-independent, global illumination solutions. The main goal is to provide experimental proof that relaxing the requirement for well-shaped mesh (i.e. allowing disproportions in size and shape of mesh elements, e.g. long, thin triangles) and using variable luminance thresholds to adaptively control mesh subdivision can significantly reduce the number of mesh elements without degrading shading quality. As a result, total time of the lighting simulation is shortened, and subtle shading details can be revealed where other algorithms fail.
Key words: global illumination, meshing algorithms.

Chrzaszcz J.R.:
Monitoring data stream in a visual system.
MGV vol. 3, no. 4, 1994, pp. 611-623.

Designing visual system is a complex task that must be supported with appropriate software tools. Behavioral simulation is perceived as feasible technique for deriving reliable predictions of system performance. In order to obtain meaningful results the model parameters as well as data stream characteristics should reflect reality. The application considered here is flight simulation and this paper presents a method for determining data stream properties, such as distribution of number and size of objects falling into pilot's field of view. Developed approach requires a six-dimensional observation space (3 position coordinates and 3 orientation angles) to be scanned with a synthetic camera. For each sampling point the data base containing terrain description is traversed and statistics of visible objects are recorded.
The problem and its background are outlined first, then solution concept and generic algorithm is described and, finally, the implementation and results are discussed.
Key words: visual system, flight simulation, data stream properties, pilot's observation space.

Skala V., Kolingerova I., Blaha P.:
A comparison of 2D line clipping algorithms.
MGV vol. 3, no. 4, 1994, pp. 625-633.

A comparative study of new line clipping algorithms for 2D convex polygons is presented and the evaluation of algorithms' efficiency based on theoretical analysis and experimental results is given. Complexity of all compared algorithms is O(N).
Key words: line clipping, convex polygon, dual space application, computer graphics.

Bak R., Kasinski A.:
A fast algorithm for hidden faces removal with application to animated geometrical modellers.
MGV vol. 3, no. 4, 1994, pp. 635-644.

Animated geometrical models are used in CAD/CAE systems for planning tasks of robots. This is an application where the readability of the dynamic picture is of primary importance. In perspective, which is used to present 3D views of the robot workcell, good readability is achieved by the shading and elimination of hidden surfaces. We propose an algorithm for solving visibility dilemmas for the case of dynamic, articulated structures made of convex polytopes. The algorithm has been implemented as a kernel of the robot scene modeller and trajectory planner. The performance of the image generation process as compared with algorithms based on known methods improved considerably. A scene with a six - DOF robot and obstacles, with all elements shaded, could be animated in real-time even using PC.

Klopotek M.A.:
Recovery of structure of looped jointed objects from multiframes.
MGV vol. 3, no. 4, 1994, pp. 645-656.

A method to recover structural parameters of looped jointed objects from multiframes is being developed. Each rigid part of the jointed body needs only to be traced at two (that is at junction) points. This method has been linearized for 4-part loops, with recovery from at least 19 frames.

Kierzenkowski K., Puchalski J.:
Object contour recognition using oriented grids.
MGV vol. 3, no. 4, 1994, pp. 657-665.

In this paper an oriented grid method (OGM) is proposed for pattern recognition. OGM is a circular scanning method based on the centroid of the contour and a reference vector of the object. First, we extract the set of features of the object from vectorial representation of its contour at the centre of its gravity. Next, the way to find the reference vector of the object contour is proposed. The grid operator which is composed of translation, rotation and decomposition is applied. This operator enables to represent object contour as a two dimensional matrix invarianting to scal, translations and rotations. This approach, using regular square grid, is demonstrated to recognize objects without symmetry or with one symmetry axis. The method has been verified experimentally and its sensitivity to the mirror image transformation is shown.

Asselin de Beauville J.-P., Bi D., Langlais L.:
Texture segmentation using grey levels rank-vectors.
MGV vol. 3, no. 4, 1994, pp. 667-674.

Texture is often defined as the repetition of primitives. Following this definition, a rank-vector is presented to obtain the texture primitives, the histogram of which is calculated in a region to extract the texture features, by clustering the histograms in different regions, a supervised texture segmentation algorithm is developed. The results have shown that the method presented in this paper is effective for a variety of textures.
Key words: texture definition, texture features, segmentation, texture analysis, clustering, rank-vector.

Michelitsch T.:
A quasi-Julia set generated by a nonanalytic trigonometric function.
MGV vol. 3, no. 4, 1994, pp. 677-679.

A mapping generated by a nonanalytic trigonometric function with manipulated imaginary part is presented. Its quasi-Julia set yields surprising, almost circular disks. A Riemann projection of this quasi-Julia set appears like a moon with craters.
Key words: Mandelbrot set, Julia set, nonanalytic mapping, quasi-Julia set, Riemann sphere.

Kurianski A.:
Detection and motion tracking by means of spatio-temporal modelling of images using random fields. [Dissertation Abstract]
MGV vol. 3, no. 4, 1994, p. 681.

Revievers' index

Authors' index

Contents of volume 3, 1994