• Journal of Korea Multimedia Society
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• v.14 no.5
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• pp.691-702
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• 2011

Recently, several researchers have attempted to combine human visual perception and computer graphics. Cole et. al. suggest the study results in which line drawing algorithm in computer graphics characterize the properties of line drawing made by artists. The paper also evaluates CG line drawing algorithms depending on whether people recognize effectively specific 3D shape from the image made by those CG line drawing algorithms. However, human recognizes the shape of objects more effectively in image made by BRDF shading model than line drawing algorithm. It means that the shading factor is important to recognize shape with human perception. In this paper, we analyze the correlation between shading made by human artists and that made by CG shading algorithms. The study is to characterize the mathematical properties of artists' shading and CG shading. This type of analysis can guide the future development of new CG shading algorithm in computer graphics for the purpose of shape perception.

• Journal of Korea Multimedia Society
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• v.14 no.8
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• pp.1082-1093
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• 2011

Traditional rendering of cartoon character cannot revive the feeling of concept drawings properly. In this paper, we propose capture technology to get toon shading model from the concept drawings and with this technique, we provide a new novel system to render 3D cartoon character. Benefits of this system is to cartoonize the 3D character according to saliency to emphasize the form of 3D character and further support the sketch-based user interface for artists to edit shading by post-production. For this, we generate texture automatically by RGB color sorting algorithm to analyze color distribution and rates of selected region. In the cartoon rendering process, we use saliency as a measure to determine visual importance of each area of 3d mesh and we provide a novel cartoon rendering algorithm based on the saliency of 3D mesh. For the fine adjustments of shading style, we propose a user interface that allow the artists to freely add and delete shading to a 3D model. Finally, this paper shows the usefulness of the proposed system through user evaluation.

• The Journal of the Korea Contents Association
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• v.11 no.6
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• pp.106-115
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• 2011

In this paper, we evaluate the effectiveness of previous shading algorithms in depicting shape of 3d objects. We perform a study in which people are shown an image of one of ten 3D objects shaded with one of eight styles and asked to orient a gauge to coincide with the surface normal at many positions on the object's surface. The normal estimates are compared with each other and with ground truth data provided by a registered 3D surface model to analyze accuracy and precision. Our experiments suggest that people interpret certain shape differently depending on shading of 3d object. This paper offers substantial evidence that current computer graphics shading algorithms can effectively depict shape of 3d objects where the algorithms have the properties of lots of tone steps and uniformly distributed tone steps. This type of analysis can guide the future development of new CG shading algorithms in computer graphics for the purpose of shape perception.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.3
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• pp.58-67
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• 2008

In this paper, we first point out difficulties faced by CG artists in the shading process: (1) a lot of technical details on shaders required, (2) long rendering time, and (3) repeated trials-and-errors. To make them overcome such difficulties, we propose Shader Space Navigator, a system that efficiently searches for shaders similar to a given query shader from a shader database containing a large number of quality shaders. With Shader Space Navigator, CG artists find appropriate shaders from the database that are very close to the final result shader, and thus complete the shading process easily by slightly tuning some attributes of those shaders. Thus, the CG artists can create their final shaders in an intuitive and efficient way without a large number of time-consuming rendering processes. Also, we deal with implementation issues related to Shader Space Navigator and constructing an abundant shader database in detail.

• Journal of Korea Multimedia Society
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• v.18 no.5
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• pp.671-681
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• 2015

This paper presents an extended scientific visualization for the public over the scientific visualization targeting for scientists. Our scientific visualization pursues both transmission of scientific information and good-looking visuals. First of all, we examine a tendency to produce scientific images that make the public understand science, even though they are not professional scientists. As a result, we can find several cases that actively generate scientific visualizations for the public. Among them, several research institutes possess own production studio. As the production of scientific images is a convergence field combined of art and science, cooperation between artists and scientists is necessary. Therefore, in-depth communication between them is essential at the planning stage. Moreover, continuous feedbacks between two groups in the production stage, the next stage of the planning, make the scientific visualization to perfection. In this paper, we present 2 modeling methods that are easily encountered during producing scientific visualizations and shading and rendering methods for generating photorealistic images. The concept of an extended scientific visualization that we present shows a new vision of the scientific visualization field.

• Journal of the Korea Computer Graphics Society
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• v.15 no.2
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• pp.19-34
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• 2009

This paper presents an automatic rendering system for 3D meshes which generates images in the style of oriental black ink painting. In this paper, we analyze the characteristics of black ink painting and present some requirements for our black ink rendering system. Then we survey the steps used by artists to create black ink paintings. Based on the analysis of drawing steps, we propose a black ink rendering system which reproduces the key features of black ink painting through three sub-systems: the feature line layer, the interior shading layer, and the media layer. The main contribution of this paper is to introduce new methods which generate realistic and natural results very fast while any simulation methods are not used to satisfy real-time performance. We describe our implementation of each of these, and demonstrate our results in the major three styles of black ink painting: the outline style, the spontaneous style, and the outline-spontaneous style. Our system renders 3D models of moderate complexity at interactive frame rates. As a result, we expect that our system can be directly applied to real-time applications such as computer games and virtual environments.

• Cartoon and Animation Studies
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• s.33
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• pp.31-53
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• 2013

In the early twentieth century, history of animation began by modern artists, they produced various experimental images with the newly invented film and cameras. Artists in the field of movie, photography, paintings and others manipulated images in motion. But as some animated movies won industrial success and popularity, they became the trend but experimental style of early animation preserved by so-called non-mainstreamers or experimental animators, counteracting commercialism. Disney animation also followed the trend by applying realistic Hollywood film style, the worse critics placed a low value on the animation and it tarnished the image, although it was profitable investment from a business standpoint. To make images realistic, they opened a drawing class that animators developed skills to imitate motions and forms from subjects in real life. Also some techniques and gizmos were used to mimic and simulate three dimensional objects and spaces, multiplane camera and compositing 3D CG images with 2D drawings. Moreover, they brought animation stories from fairly tales or folk tales, and Walt's personal interest in live-action movies, they applied Hollywood-film-like narratives and realistic visual, and harsh criticism ensued. On the surface early disney animations' potential seems to be weakened, but in reality it still exists by simplifying and exaggerating forms and color as modern arts. Disney animation employs concepts of the modernism paintings such as simplified shapes and colors to a character design, when their characters are placed together in a scene, that visual elements cause mental reaction. This modification gives a new internal experience to audiences. As conceptual colors in abstract paintings make images appeared to be flat, coloring characters with no shading make them look flat and comparing to them, background images are also appeared to be flat. On top of that, multi-perspective at background images recalls modernist paintings. This essay goes in details with the animation pioneers' works and how Disney animation developed its techniques to emulate real life and analyses color schemes, forms, and spaces in Disney animation compared with modern artists' works, in that the visual language of Disney animation reminds of impression from abstract paintings in the beginning of the twentieth centuries.