• Proceedings of the IEEK Conference
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• 2003.11b
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• pp.107-110
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• 2003

In this paper, we propose sharing 3D media between multisite using enhanced Access Grid (e-AG) which is a composition of 3D display and Access Grld (AG) Conventional AG and other collaborative systems have a limitation to share immersive 3D media Thus, proposed system supports sharing 3D media contents in a AG meeting section. Real object can be shared by acquiring stereo image with pre-calibrated stereo camera and by delivering, and virtual object can be shared by transmitting state information after downloading 3D model. And also, real video scene acquired by stereo camera and virtual object from 3D model can be displayed on the 3D display system of each node adaptively. The characteristics of proposed sharing method are sharing 3D media, displaying 3D media on a system adaptively, supporting real-time interaction. The proposed sharing method will be used remote lecture, remote collaboration with 3D media.

• ETRI Journal
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• v.36 no.4
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• pp.662-672
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• 2014

Human action recognition is used in areas such as surveillance, entertainment, and healthcare. This paper proposes a system to recognize both single and continuous human actions from monocular video sequences, based on 3D human modeling and cyclic hidden Markov models (CHMMs). First, for each frame in a monocular video sequence, the 3D coordinates of joints belonging to a human object, through actions of multiple cycles, are extracted using 3D human modeling techniques. The 3D coordinates are then converted into a set of geometrical relational features (GRFs) for dimensionality reduction and discrimination increase. For further dimensionality reduction, k-means clustering is applied to the GRFs to generate clustered feature vectors. These vectors are used to train CHMMs separately for different types of actions, based on the Baum-Welch re-estimation algorithm. For recognition of continuous actions that are concatenated from several distinct types of actions, a designed graphical model is used to systematically concatenate different separately trained CHMMs. The experimental results show the effective performance of our proposed system in both single and continuous action recognition problems.

• Journal of Multimedia Information System
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• v.5 no.2
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• pp.83-86
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• 2018

Owing to high speed internet technologies, video conferencing systems are exploited in our home as well as work places using a laptop or a webcam. Although eye contact in the video conferencing system is significant, most systems do not support good eye contact due to improper locations of cameras. Several ideas have been proposed to solve the eye contact problem; however, some of them require complicated hardware configurations and expensive customized hardwares. In this paper, we propose a simple eye gaze correction method using the three-dimensional (3D) affine transformation. We also apply an image in-painting method to fill empty holes that are caused by round-off errors from the coordinate transformation. From experiments, we obtained visually improved results.

• Journal of Information Processing Systems
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• v.9 no.1
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• pp.53-68
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• 2013

We investigate the rate-compatible punctured convolutional (RCPC) codes concatenated with hierarchical QAM for designing a cross-layer unequal error protection scheme for H.264 coded sequences. We first divide the H.264 encoded video slices into three priority classes based on their relative importance. We investigate the system constraints and propose an optimization formulation to compute the optimal parameters of the proposed system for the given source significance information. An upper bound to the significance-weighted bit error rate in the proposed system is derived as a function of system parameters, including the code rate and geometry of the constellation. An example is given with design rules for H.264 video communications and 3.5-4 dB PSNR improvement over existing RCPC based techniques for AWGN wireless channels is shown through simulations.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.4
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• pp.110-122
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• 2014

As multimedia technologies develop, three-dimensional (3D) technologies are attracting increasing attention from researchers. In particular, video quality assessment (VQA) has become a critical issue in stereoscopic image/video processing applications. Furthermore, a human visual system (HVS) could play an important role in the measurement of stereoscopic video quality, yet existing VQA methods have done little to develop a HVS for stereoscopic video. We seek to amend this by proposing a 3D visual attention (3DVA) model which simulates the HVS for stereoscopic video by combining multiple perceptual stimuli such as depth, motion, color, intensity, and orientation contrast. We utilize this 3DVA model for pooling on significant regions of very poor video quality, and we propose no-reference (NR) stereoscopic VQA (SVQA) method. We validated the proposed SVQA method using subjective test scores from our results and those reported by others. Our approach yields high correlation with the measured mean opinion score (MOS) as well as consistent performance in asymmetric coding conditions. Additionally, the 3DVA model is used to extract information for the region-of-interest (ROI). Subjective evaluations of the extracted ROI indicate that the 3DVA-based ROI extraction outperforms the other compared extraction methods using spatial or/and temporal terms.

• Korean Journal of Digital Imaging in Medicine
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• v.5 no.1
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• pp.26-31
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• 2002

This paper represents the design of 3D endoscopic video system in order to improve visualization and enhance the ability of the surgeon to perform delicate endoscopic surgery. Minimally invasive techniques have set new standards in all surgical may experience less post-operative discomfort, shorter hospitalization, and quicker recuperation. Finally, the aim of the present study was to determine the influence of 2D and 3D video imaging on defined tasks on a laparoscopic trainer.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.4
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• pp.559-565
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• 2011

In this paper, we propose the geographic information systems that is able to build geographic information effectively by creating 3D topography after extraction surrounding terrain information through the video shooting in the CCTV camera. We also propose tracing method for object recognized through the video shooting of camera and recognition method which is whether or not the terrain change according to success or not of tracing the object. We apply this method in the industry field we can build a geographic information close to the actual terrain, but also can be used for security, surveillance and tracking system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.10C
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• pp.813-819
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• 2008

In this paper, we implemented a real-time system which displays 3-dimensional (3D) stereoscopic image with stereo camera. The system consists of a set of stereo camera, FPGA board, and 3D stereoscopic LCD. Two CMOS image sensor were used for the stereo camera. FPGA which processes video data was designed with Verilog-HDL, and it can accommodate various resolutional videos. The stereoscopic image is configured by two methods which are side-by-side and up-down image configuration. After the left and right images are converted to the type for the stereoscopic display, they are stored into SDRAM. When the next frame is inputted into FPGA from two CMOS image sensors, the previous video data is output to the DA converter for displaying it. From this pipeline operation, the real-time operation is possible. After the proposed system was implemented into hardware, we verified that it operated exactly.

• Journal of Communications and Networks
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• v.14 no.3
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• pp.286-295
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• 2012

To meet the increased demand of video-on-demand (VoD) services, peer-to-peer (P2P) mesh-based multiple video approaches have been recently proposed, where each peer is able to find a video segment interested without resort to the video server. However, they have not considered the constraint of the server's upload bandwidth and the fairness between upload and download amounts at each peer. In this paper, we propose a novel P2P VoD streaming system, named peer cache adaptation (PECAN) where each peer adjusts its cache capacity adaptively to meet the server's upload bandwidth constraint and achieve the fairness. For doing so, we first propose a new cache replacement algorithm that designs the number of caches for a segment to be proportional to its popularity. Second, we mathematically prove that if the cache capacity of a peer is proportional to its segment request rate, the fairness between upload and download amounts at each peer can be achieved. Third, we propose a method that determines each peer's cache capacity adaptively according to the constraint of the server's upload bandwidth. Against the proposed design objective, some selfish peers may not follow our protocol to increase their payoff. To detect such peers, we design a simple distributed reputation and monitoring system. Through simulations, we show that PECAN meets the server upload bandwidth constraint, and achieves the fairness well at each peer. We finally verify that the control overhead in PECAN caused by the search, reputation, and monitoring systems is very small, which is an important factor for real deployment.

• Journal of Broadcast Engineering
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• v.19 no.5
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• pp.640-655
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• 2014

Many of today's video systems have additional depth camera to provide extra features such as 3D support. Thanks to these changes made in multimedia system, it is now much easier to obtain depth information of the video. Depth information can be used in various areas such as object classification, background area recognition, and so on. With depth information, we can achieve even higher coding efficiency compared to only using conventional method. Thus, in this paper, we propose the 2D video coding algorithm which uses depth information on top of the next generation 2D video codec HEVC. Background area can be recognized with depth information and by performing HEVC with it, coding complexity can be reduced. If current CU is background area, we propose the following three methods, 1) Earlier stop split structure of CU with PU SKIP mode, 2) Limiting split structure of CU with CU information in temporal position, 3) Limiting the range of motion searching. We implement our proposal using HEVC HM 12.0 reference software. With these methods results shows that encoding complexity is reduced more than 40% with only 0.5% BD-Bitrate loss. Especially, in case of video acquired through the Kinect developed by Microsoft Corp., encoding complexity is reduced by max 53% without a loss of quality. So, it is expected that these techniques can apply real-time online communication, mobile or handheld video service and so on.