• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.11 no.8
• /
• pp.1442-1449
• /
• 2007

Shadows are important elements for realistic rendering of the 3D scene. We cannot recognize the distance of objects in the 3D scene without shadows. Two methods, image-based medthods and object-based methods, are largely used for the rendering of shadows. Object based methods can generate accurate shadow boundaries. However, it cannot be used to generate the realtime shadows because the time complexity defends on the complexity of the 3D scene. Image based methods which are techniques to generate shadows are widely used because of fast calculation time. However, this algorithm has aliasing problems. PCF is a method to solve the aliasing problem. Using PCF technique, antialiased shadow boundaries can be generated. However, PCF with large filter size requires more time to calculate antialiased shadow boundaries. This paper proposes an improved PCF technique which generates antialiased shadow boundaries similar to that of PCF. Compared with PCF, this technique can generate antialiased shadows in less time.

• International Journal of Internet, Broadcasting and Communication
• /
• v.15 no.2
• /
• pp.157-167
• /
• 2023

As a new trend in the development of urban public spaces, the use of right-angle LED screens perfectly combines building facades with naked-eye 3D visual effects, providing designers with a brand-new creative platform. How to create a realistic naked-eye 3D effect on a right-angle LED screen and bring an immersive visual experience to the audience has become a question worth exploring. So far, production companies have yet to announce the relevant design ideas and complete production methods. In order to explore the production principle and production process of the naked-eye 3D effect of the right-angle LED screen, we summarize the basic production principle of the naked-eye 3D impact of the right-angle LED screen through case analysis. Based on understanding the production principle, the actual case production test was carried out, and a complete production process of the naked eye 3D visual effect of the right-angle led screen was tried to be provided by off-line rendering. For the problem of how to deal with image deformation, we provide two production methods: post-production software correction and UV mapping. Among them, the UV mapping method is more efficient and convenient. Referring to this paper can help designers quickly understand the production principle of the naked eye 3D effect of right-angle LED screens. The production process proposed in this paper can provide a reference for production method for related project producers.

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.5
• /
• pp.821-830
• /
• 2023

The advancement of Internet network technology has triggered the emergence of new OTT video content platforms, increasing demand for content and altering consumption patterns. This trend is bringing positive changes to the South Korean animation industry, where diverse and high-quality animation content is becoming increasingly important. As investment in technology grows, video production technology continues to advance. Specifically, 3D animation and VFX production technologies are enabling effects that were previously unthinkable, offering detailed and realistic graphics. The Fourth Industrial Revolution is providing new opportunities for this technological growth. The rise of Artificial Intelligence (AI) is automating repetitive tasks, thereby enhancing production efficiency and enabling innovations that go beyond traditional production methods. Cutting-edge technologies like 3D animation and VFX are being continually researched and are expected to be more actively integrated into the production process. Digital technology is also expanding the creative horizons for artists. The future of AI and advanced technologies holds boundless potential, and there is growing anticipation for how these will elevate the video content industry to new heights.

• Journal of Broadcast Engineering
• /
• v.20 no.1
• /
• pp.68-81
• /
• 2015

Owing to the latest development of component and media processing technologies, UHDTV as a successor of the HDTV is expected that this will be coming soon realization. Accordingly, an audio technology that provides a 5.1-channel surround sound in home should be contemplating on what services should be provided with the advent of UHDTV era. In fact, however, the market of 5.1-channel audio is struggling, due to the difficulty of installation and maintenance of the multi speakers in a home. Meanwhile, the movie sound market for a long time been used in 5.1 and 7.1-channel sound formats, have changed as Dolby ATMOS, IOSONO, AURO3D etc. are launched one after another with the introduction of hybrid audio technologies that include the ceiling and object-based sounds. This very object-based audio technology is assured to be introduced in the home theater and broadcast audio market, and this change in audio technology is expected to be a breath of pioneering technological advances and market growth from the channel-based audio market that lacks flexibility. In this paper, we will investigate a suitable realistic audio solution for UHDTV, and introduce hybrid audio technologies, which is expected to be an audio technology for UHDTV, and we will describe the hybrid audio content format and reproduction methods in a home and consider the future prospects of realistic audio.

• 한국HCI학회:학술대회논문집
• /
• 2009.02a
• /
• pp.203-213
• /
• 2009

Medicine is one of great application fields where Virtual Reality (VR) technologies have been successfully utilized. The VR technologies in medicine bring together an interdisciplinary community of computer scientists and engineers, physicians and surgeon, medical educator and students, military medical specialists, and biomedical futurists. The primary feedback of a VR system has been visual feedback. The complex geometry for graphic objects and utilizing hardware acceleration can be incorporated with in order to produce realistic virtual environments. To enhance human-computer interaction (HCI), in term of immersive experiences perceived by users, haptic, speech, olfactory and other non-traditional interfaces should also be exploited. Among those, hapic feedback has been tightly coupled with visual feedback. The combination of the two sensory feedbacks can give users more immersive, realistic and perceptive VR environments. Haptic feedback has been studied over decades and many haptic based VR systems have been developed. This paper focuses on haptic feedback in term of its medical usages. It presents a survey of haptic feedback techniques with their applications in medicine.

• The Journal of the Korea Contents Association
• /
• v.9 no.7
• /
• pp.102-109
• /
• 2009

In this paper, we present an algorithm which generates the impossible drawings after the manner of M.C. Escher. A class of the impossible drawings, focused on this paper, depicts the non-realistic configuration such that an ascent (or a descent) looks like keeping on permanently with a height-deceptive loop. We analyze the fact that the ascending direction in the non-realistic illustrations comes not from the physical heights of the objects but from the artist's intended forwarding direction about the loop, which does not have any physical sense of depths. The basic idea to support such impossible drawings is to use a loop of layered depth images (LDIs), where several LDIs are arranged along with the forwarding direction of the loop while having the physically constant heights. The height-deception between two adjacent objects comes from the layer values in the LDIs. In this paper, we propose a NPR system which can manipulate a shape of the loop and layer values of the LDIs and demonstrate several impossible drawings results generated by using our system.

• Journal of the Korea Computer Graphics Society
• /
• v.3 no.2
• /
• pp.1-13
• /
• 1997

Two factors are required for a virtual reality system; realism and immersion. Since realism is determined primarily by the realistic image, objects in a virtual environment should be represented with details by their own characteristics. Also, reflection on light must be considered. On the other hand, immersion is defined as realistic movements and fast interactions. Thus, virtual environment should be rendered as fast as possibl. Regular frame rate should also be kept to make moves as intended by the user. In a complex virtual environment composed of objects with various levels, the appropriate level for individual object should be assigned according to the view point, in other words, the selection of level-of-detail is needed. In this paper, the problem of determining the levels of detail is formalized in terms of error, cost and L -distance. Error is defined as the difference between the current level image and the highest level image, cost as rendering time, and L-distance as the level difference between the previous and the current level. To solve this problem, a new method called the well-distributed adaptive algorithmis proposed.

• 한국HCI학회:학술대회논문집
• /
• 2008.02a
• /
• pp.426-432
• /
• 2008

We introduce a method of rendering a scene lying 3D objects which is like that artist draw on a canvas by brushing. Painting is the art area presenting something created by color and line on 2D plane. We are brushing on billboards on screen space for the 2D brushing effect according to the definition of "Painting". Brushing orientation is haven to rotate for preventing the orientation in the first scene in the case that object or camera are moving. If the brushing isn't rotated, shower-door effect is watched on the scene as undesirable result We present a brushing rotating method for keeping the orientation changing the direction of view and object rigid animation. The brushing direction is computed with Horn's 2D similarity transform by least-square solution. We watched the changing brushing to track the motion of object and view.

• Journal of Mechanical Science and Technology
• /
• v.20 no.1
• /
• pp.29-41
• /
• 2006

Nowadays, with the advancement of computers, computer simulation linked with VR (Virtual Reality) technology has become a useful method for designing the automotive driving system. In this paper, the VR simulation system was developed to investigate the driving performances of the ASV (Advanced Safety Vehicle) equipped with an ACC (Adaptive Cruise Control) system. For this purpose, VR environment which generates visual and sound information of the vehicle, road, facilities, and terrain was organized for the realistic driving situation. Mathematical models of vehicle dynamic analysis, which includes the ACC algorithm, have been constructed for computer simulation. The ACC algorithm modulates the throttle and the brake functions of vehicles to regulate their speeds so that the vehicles can keep proper spacing. Also, the real-time simulation algorithm synchronizes vehicle dynamics simulation with VR rendering. With the developed VR simulation system, several scenarios are applied to evaluate the adaptive cruise controlled vehicle for various driving situations.

• Journal of Korea Game Society
• /
• v.16 no.2
• /
• pp.111-118
• /
• 2016

Global illumination is key factor for realistic image but it is not common in realtime rendering due to its complexity. Visibility of $2^{nd}$ lights is hard to determine because we should process all object for each $2^{nd}$ light. In this paper, we reuse visibility of static objects. We present an indirect illumination algorithm which shows good performance and provides exact $2^{nd}$ light visibility when the scene has small number of moving objects. Our method renders correct image while showing good performance.