• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1999.06a
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• pp.145.1-149
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• 1999

In Computer Graphics, Phong shading algorithm is essential and also sufficient for producing realistic images. In this paper, we propose an approach taking only two additions and one memory access for shading a pixel. A Phong-Shading table is used for storing the values of diffuse and specular components of the Phong reflection model. The intensity of a pixel can be obtained by table lookup. The performance of proposed method is almost the same as Gouraud shading.

• Journal of the Korea Computer Graphics Society
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• v.6 no.3
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• pp.1-7
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• 2000

The number of pixels being processed in a raster graphics system often exceeds 1 million per frame. Replacing fractional arithmetic by integer arithmetic on rendering graphics primitives will therefore significantly improve the rendering performance. A scaling method that replaces fractional arithmetic by integer arithmetic on rendering graphics primitives is introduced. This method is applied to the filtered edge drawing and Gouraud shading. This method will also be applicable to some of other incremental algorithms for rendering graphics primitives. Because the scaling method requires only simple modifications upon the known algorithms that already have been implemented in ASIC (Application Specific Integrated Circuit), our algorithms can easily be implemented in ASIC. Our method will be useful especially for the low-price systems (e.g., home game machines, personal computers, etc.).

• Journal of Digital Contents Society
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• v.9 no.4
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• pp.771-778
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• 2008

A Device performance analyzing method for appropriate level in hybrid rendering model is suggested. In recent research, we proposed a hybrid rendering model which is applying a proper shading method to each of polygons consisting of an object. The number of polygon for Gouraud shading and that for flat shading should be considered according to a current device performance and system environments. Therefore, this paper suggests the method to calculate automatically a proper resolution of a mesh of object and a proper level of mixture between Gouraud and a flat shading, considering a current device performance and a preference of end-user. The rendering model is so simple that it can be an efficient replacement to reduce a real-time rendering time since it provides automatically multi-level of rendering resolution to an executing environments. Moreover, it can be adopted in real-time adaptive service for 3D graphic contents like a graphic game under various device environments.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.730-735
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• 1991

In this paper, a graphics system supporting PHIGS and PHIGS+ is suggested and its hardware structure and software are described. The developed graphics system is a multi-processing system that uses 6 i860 RISC CPU's and supports PHIGS and PHIGS+ language in a hardware level. The developed system under tested is able to draw 160, 000 3-D polygones in one second when each polygon has 100 pixels and is shaded with Gouraud shading.

• Journal of Digital Contents Society
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• v.9 no.3
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• pp.509-516
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• 2008

We propose the Hybrid Rendering model to support multi-resolution for computer graphics. LOD method for computer graphics system considering performance of device environment and end-user preference usually adopts mesh resolution, mipmap in texture rendering, or oct-tree data structure in ray tracing. The hybrid rendering model, as a local shading model combining Gouraud shading model and a flat shading model, applies a proper shading method to each of polygons consisting of an object. This method can be an effective alternative to reduce real-time rendering time so that it can be utilized in real time adaptive service of computer graphic contents among various device environments under ubiquitous environments.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.313-315
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• 2010

In this paper, we describe research results of developing hardware rasterizer that is applicable to mobile 3D graphics system, designed in SIMD architecture and verified in FPGA. Tile-based scan conversion unit is designed like SIMD architecture running four tiles simultaneously and each tile traverses pixels hierarchical in 3-level so that visiting counts is minimized. As experimental results, $8{\times}8$ is the most efficient size of tile and the last step of tile traversing is performed on $2{\times}2$ sized subtile. The rasterizer supports flat shading and gouraud shading and texture mapper supports affine mapping and perspective corrected mapping. Also, texture mapper supports point sampling mode and bilinear interpolating sampling mode and two types of wrapping modes and various blending modes. The rasterzer operates as 120Mhz on xilinx vertex4 $l{\times}100$ device. To easy verification, texture memory and frame buffer are generated as block rom and block ram.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.28-30
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• 2009

This paper describes a 3-DTIP(3-D Tour Into Picture) using depth map for a Korean classical painting being composed of persons and landscape. Unlike conventional TIP methods providing 2-D image or video, our proposed TIP can provide users with 3-D stereoscopic contents. Navigating inside a picture provides more realistic and immersive perception. The method firstly makes depth map. Input data consists of foreground object, background image, depth map, foreground mask. Firstly we separate foreground object and background, make each of their depth map. Background is decomposed into polygons and assigned depth value to each vertexes. Then a polygon is decomposed into many triangles. Gouraud shading is used to make a final depth map. Navigating into a picture uses OpenGL library. Our proposed method was tested on "Danopungjun" and "Muyigido" that are famous paintings made in Chosun Dynasty. The stereoscopic video was proved to deliver new 3-D perception better than 2-D video.