• The Journal of Korea Robotics Society
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• v.11 no.4
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• pp.300-309
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• 2016

This paper proposes a method for motion estimation of consecutive cameras using 3-D straight lines. The motion estimation algorithm uses two non-parallel 3-D line correspondences to quickly establish an initial guess for the relative pose of adjacent frames, which requires less correspondences than that of current approaches requiring three correspondences when using 3-D points or 3-D planes. The estimated motion is further refined by a nonlinear optimization technique with inlier correspondences for higher accuracy. Since there is no dominant line representation in 3-D space, we simulate two line representations, which can be thought as mainly adopted methods in the field, and verify one as the best choice from the simulation results. We also propose a simple but effective 3-D line fitting algorithm considering the fact that the variance arises in the projective directions thus can be reduced to 2-D fitting problem. We provide experimental results of the proposed motion estimation system comparing with state-of-the-art algorithms using an open benchmark dataset.

• Journal of Advanced Navigation Technology
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• v.11 no.1
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• pp.99-104
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• 2007

On-line avatar community service requires natural representation of communication, emotional expression, and popular dances and various kinds of services. The space should be dynamic, and the interaction between the motions of avatars and the space is required. The avatars with their national, interesting, and various motions should be implemented togetherwith interaction with virtual spaces, in order to have competition in developing 3D avatars. It is expected for 3D avatars to be broadly applied for 3D shopping malls for e-commerce, cyber model houses, 3 D simulations, and 3D virtual reality game. Therefore, for one line 3D avatar community services, we try to provide the scheme for making interactive virtual spaces, together with 3D avatar animations.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.2
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• pp.151-157
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• 1990

This paper presents a method for rapid wire frame drawing of the 3D objects represented by the CSG scheme. When the two CSG trees are combined into one, the intersection parts of the polygons constituting the object corresponds to each subtree are computed, and the boundary representation of the combined object is obtained according to the given combinational operator and stored in the root node. The boundary representation in the root node is used in the wireframe drawing of the object and later computation of boundary representation. Bezier surface is taken as one of the primitive object the scan-line algorithm is used, which subdivides each scan-line into the spans where no polygon is intersected, and renders each span with the CSG representation of the object.

• Journal of Environmental Science International
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• v.28 no.11
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• pp.1047-1059
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• 2019

To address the increase of weather hazards and the emergence of new types of such hazards, an optimization technique for three-dimensional (3D) representation of meteorological facts and atmospheric information was examined in this study as a novel method for weather analysis. The proposed system is termed as "meteorological and air quality information visualization engine" (MAIVE), and it can support several file formats and can implement high-resolution 3D terrain by employing a 30 m resolution digital elevation model. In this study, latest 3D representation techniques such as wind vector fields, contour maps, stream vector, stream line flow along the wind field and 3D volume rendering were applied. Implementation of the examples demonstrates that the results of numerical modeling are well reflected, and new representation techniques can facilitate the observation of meteorological factors and atmospheric information from different perspectives.

• Journal of Korea Society of Industrial Information Systems
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• v.8 no.4
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• pp.55-63
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• 2003

The game & multimedia industry is a high-valued industry comparing to any industry. Also, it has been shown the possibility as considerably bright future industry due to a development of the Internet, an explosive growth of on-line game market, and a union with virtual reality technology Since an on-line game having a clear profit model is expanding to PC and other platform, it brings to us a large change throughout the whole game industry. In order to develop a game, we need a number of elements. A game character among them delivers to a user the overall characteristics of a game as a visual representation and makes us access to a game directly and sensuously. A game character of on-line game is considerable in an operation in the volume of initial sales from a viewpoint of marketing. In addition, it affects to secure users and be immersed in a game. In this paper, we propose a production skill of an efficient 3D game character for 3D on-line game.

• Journal of the Optical Society of Korea
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• v.14 no.4
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• pp.310-315
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• 2010

Theoretical and experimental investigations of moires in 3D displays were performed. To describe and minimize moires, we propose the polar representation form of moire waves. The experimental and theoretical data are in good agreement except in the neighborhood of the minimization angle. The implicit formulas are found for visible moires of line gratings at finite distances. The computer simulation and the physical experiments confirm the moire appearance for this case.

• Journal of Ocean Engineering and Technology
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• v.9 no.2
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• pp.83-88
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• 1995

In this paper, the solid modeller suitable for PC was developed for Top-down 3-D representation and analysis of fixed offshore structures. Also solid modelling and hidden line removal were conducted in order to visualize the offshore structures based on the scan line z-buffer algorithm.

• Journal of information and communication convergence engineering
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• v.9 no.3
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• pp.315-318
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• 2011

The orientation space representation is constructed by treating the orientation parameters, which Gabor filters can be turned, as a continuous variable. The problem of multiple orientation line segmentation is dealt with by thresholding 3D images of the orientation space and then detecting the connected components therein. In this way, X-junctions and T-junctions are able to be separated effectively. Experimental results are presented using synthesized image.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.3
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• pp.235-244
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• 2000

This paper addresses a new method for constructing surface representation of 3D structures from a sequence of tomographic cross-sectional images, Firstly, we propose cell-boundary representation by transforming the cuberille space into cell space. A cell-boundary representation consists of a set of boundary cells with their 1-voxel configurations, and can compactly describe binary volumetric data. Secondly, to produce external surface from the cell-boundary representation, we define 19 modeling primitives (MP) including volumetric, planar and linear groups. Surface polygons are created from those modeling primitives using a simple table look-up operation. Comparing with previous method such as Marching Cube or PVP algorithm, our method is robust and does not make any crack in resulting surface model. Hardware implementation is expected to be easy because our algorithm is simple(scan-line), efficient and guarantees data locality in computation time.

• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.4
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• pp.535-542
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• 1986

In this paper, a hidden surface removal algorithm that generates a perspective view of three space plane-faced objects using scan line coherence is proposed. In particular, the proposed algorithm deals with hidden surface elimination of penetrating objects by using the optimum span division method with minimum test for priority test of segments. Also, a hidden surface redmoval method for representing sectional view of solids by using boolean difference is described.