• ETRI Journal
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• v.38 no.6
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• pp.1114-1123
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• 2016

Multi-view video plus depth (MVD) has been widely used owing to its effectiveness in three-dimensional data representation. Using MVD, color videos with only a limited number of real viewpoints are compressed and transmitted along with captured or estimated depth videos. Because the synthesized views are generated from decoded real views, their original reference views do not exist at either the transmitter or receiver. Therefore, it is challenging to define an efficient metric to evaluate the quality of synthesized images. We propose a novel metric-the reduced-reference quality metric. First, the effects of depth distortion on the quality of synthesized images are analyzed. We then employ the high correlation between the local depth distortions and local color characteristics of the decoded depth and color images, respectively, to achieve an efficient depth quality metric for each real view. Finally, the objective quality metric of the synthesized views is obtained by combining all the depth quality metrics obtained from the decoded real views. The experimental results show that the proposed quality metric correlates very well with full reference image and video quality metrics.

• Journal of Broadcast Engineering
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• v.21 no.6
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• pp.878-888
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• 2016

This paper proposes an efficient method to remove the boundary artifacts of rendered views caused by damaged depth maps in the 3D video system. First, characteristics of boundary artifacts with the compression noise in depth maps are carefully studied. Then, the artifacts suppression method is proposed by the iterative projection onto convex sets (POCS) algorithm with setting the convex set in pixel and frequency domain. The proposed method is applied to both texture and depth maps separately during view rendering. The simulation results show the boundary artifacts are greatly reduced with improving the quality of synthesized views.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.11a
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• pp.270-272
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• 2011

다시점 비디오는 사용자들에게 자유로운 시점 선택 및 넓은 시점에서의 입체감을 제공하지만, 시점의 증가에 따른 데이터 량의 증가가 불가피하다. 이에 따라 최근 MPEG 에서는 재생되는 시점 수 보다 적은 수의 다시점 비디오와 그에 대응하는 깊이 영상 및 관련 파라미터를 메타데이터 형태로 제공하는 다시점 및 깊이 영상 부호화(MVD: Multiview plus Depth)에 대한 표준화를 진행하고 있다. 본 논문은 MVD 가 방송망에서 서비스되는 시나리오를 가정하여 다시점 비디오와 그에 대응하는 깊이 영상을 MPEG-2 TS(Transport Stream)로 전송하기 위한 기법을 제시한다. 제안한 기법은 기존의 단일 영상 및 깊이 영상을 전송하기 위한 부가비디오스트림 서술자(Auxiliary Video Stream Descriptor) 및 MPEG-C Part 3 표준을 확장하여 다시점 비디오와 그에 대응하는 깊이 영상간의 매핑 정보 및 각 시점의 깊이 파라미터를 제공할 수 있다.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.620-624
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• 2009

In this paper, we present a new camera system combining a high-quality 3-D scanner and hybrid camera system to generate a multiview video-plus-depth. In order to get the 3-D video using the hybrid camera system and 3-D scanner, we first obtain depth information for background region from the 3-D scanner. Then, we get the depth map for foreground area from the hybrid camera system. Initial depths of each view image are estimated by performing 3-D warping with the depth information. Thereafter, multiview depth estimation using the initial depths is carried out to get each view initial disparity map. We correct the initial disparity map using a belief propagation algorithm so that we can generate the high-quality multiview disparity map. Finally, we refine depths of the foreground boundary using extracted edge information. Experimental results show that the proposed depth maps generation method produces a 3-D video with more accurate multiview depths and supports more natural 3-D views than the previous works.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.07a
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• pp.376-377
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• 2011

본 논문에서는 스테레오스코픽 영상 및 깊이 프레임 오류 은닉 알고리즘을 제안한다. i) 좌측 컬러 프레임 오류 발생시 시간적 상관관계를 이용하여 프레임을 복원한다. iii) 우측 컬러 프레임 오류 발생시 깊이 정보 및 DIBR 기법을 이용하여 좌 우 시점간의 매칭 픽셀을 예측하고, 매칭된 픽셀의 움직임 벡터 및 밝기 차이를 이용하여 프레임을 복원한다. iii) 좌측 깊이 프레임과 iv) 우측 깊이 프레임의 오류 발생시 좌 우측 컬러 프레임의 움직임 벡터를 이용하여 손실된 프레임을 복원한다. 컴퓨터 모의 실험을 통해 제안하는 알고리즘의 스테레오스코픽 컬러 및 깊이 프레임 오류 복원 성능을 확인한다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2022.06a
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• pp.51-53
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• 2022

고정된 위치를 중심으로 회전운동만 체험할 수 있는 3 자유도(DoF: Degrees of Freedom)를 넘어 위치를 변경하며 운동시차까지 포함된 6 자유도를 지원하는 몰입형 미디어에 대한 연구가 지속해서 진행되고 있다. 특히 부드러운 시점 변경을 제공하기 위해 특정 위치에서 샘플링 된 여러 개의 텍스쳐(또는 컬러) 및 깊이맵 영상(MVD: Multiview Video plus Depth)으로 구성된 다시점 영상을 통해 실제로 획득되지 않은 위치에서의 영상을 만들어내는 가상시점 합성(virtual view synthesis) 기술이 많이 사용되고 있다. 본 논문에서는 몰입형 미디어의 대표적인 데이터 형식인 다시점 영상을 실사 및 컴퓨터 그래픽스(CG: Computer Graphics) 환경에서 획득하는 방법에 관해 설명한다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.2
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• pp.375-384
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• 2016

In this paper, when stereo image, satellite view and corresponding depth maps were used as the input data, we propose a new method that convert these data to data format suitable for compressing, and then by using these format, intermediate view is synthesized. In the transmitter depth maps are merged to a global depth map and satellite view are converted to residual image corresponding hole region as out of frame area and occlusion region. And these images subsampled to reduce a mount of data and stereo image of main view are encoded by HEVC codec and transmitted. In the receiver intermediate views between stereo image and between stereo image and bit-rate are synthesized using decoded global depth map, residual images and stereo image. Through experiments, we confirm good quality of intermediate views synthesized by proposed format subjectively and objectively in comparison to intermediate views synthesized by MVD format versus total bit-rate.

• Journal of Korean Neurosurgical Society
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• v.39 no.2
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• pp.114-119
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• 2006

Objective : The authors investigate appropriate evaluation and surgical methods in treatment of the cerebral paragonimiasis accompanying epilepsy. Methods : Thirteen patients with the cerebral paragonimiasis accompanying epilepsy were included for this study. Preoperative evaluation methods included history taking, skin and serologic tests for Paragonimus westermani, neurologic examinations, computerized tomography, magnetic resonance imaging, amytal test, PET or SPECT, and video-EEG monitoring with depth and subdural grid electrodes. Seizure outcome was evaluated according to Engel's classification. Results : Surgical methods were temporal lobectomy including lesions in six, lesionectomy in five, and temporal lobectomy plus lesionectomy in two. Postoperative neurological complications were not noticed, and seizure outcomes were class I in 12 patients [92%], class II in one [8%]. Conclusion : In patients with a cerebral paragonimiasis accompanying epilepsy, further evaluation methods must be done to define the epileptogenic zone, and complete resection of the epileptogenic zone with different surgical methods should be performed for seizure control.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.254-255
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• 2016

The Human have sought convenience through advancing Science skill, The Generation that unman control all machine have came. the unman - vehicle have used and applied flight, ship, car, manufacturing all over the world. plus which, that is researching. but pros and cons of unman - vehicle is that unman control machine, It mean that unman - vehicle have high possibility which have collision with obstacle on driving. I will show you that this evading collision will be made from fuzzy control and video recognition and sensor recognition.I look for good effect for this system.

• Journal of muscle and joint health
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• v.29 no.1
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• pp.50-59
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• 2022

Purpose: This qualitative study aimed to explore the experiences of patients with diabetes provided with medication monitoring using an artificial intelligence-based smartwatch. Methods: Giorgi's descriptive phenomenological methodology was applied to collect and analyze data from November 9 to December 23, 2021. The study samples were recruited by convenience sampling, and even patients with diabetes participated in in-depth interviews via video conference and telephone calls or face-to-face visits. Results: Ten sub-themes and four themes were finally revealed. The four themes were as follows: journey with unfamiliar devices, a less-than-acceptable smartwatch, insufficient functions and content for patients with diabetes to use, and efforts for regular medication behaviors and daily monitoring of patient's health conditions. Conclusion: To effectively manage diabetic conditions using digital healthcare technologies, nursing interventions were needed to identify personal needs and consider technological, psychological, aesthetic, and socioeconomic aspects of wearable devices.