• 한국정보통신학회논문지
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• 제20권3호
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• pp.630-638
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• 2016

본 논문에서는 자연스러운 파노라마 영상 생성을 위해 SIFT와 SURF 방법보다 빠른 FAST(Features from Accelerated Segment Test)를 이용한 특징점 기반의 파노라마 영상 생성 기법을 제안한다. 다수의 영상을 이용해 자연스러운 파노라마 영상을 만들기 위해 실린더 투영을 수행 한 후 추출된 특징점들을 RANSAC(Random Sample Consensus)을 이용해 정합 시 오차율을 최소화한다. 서로 다른 방향에서 얻는 다수의 영상을 합성할 때 정합 경계 주변의 이질감을 보완하기 위해 블렌딩 기법을 사용함으로써 자연스러운 파노라마 영상을 생성한다. 제안하는 기법에서는 영상을 정합할 때 영상의 입력 순서와 방향에 관계없이 파노라마 영상을 만들 수 있다. 또한 기존의 방법보다 빠른 속도로 영상 정합이 가능하다. 다수의 영상으로 실험을 한 결과 왜곡이 보정되고 자연스러운 파노라마 영상을 생성할 수 있었다.

• 대한디지털의료영상학회논문지
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• 제14권2호
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• pp.15-22
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• 2012

The purpose of this study was to measure the absorbed dose and calculate the effective dose for cone beam computed tomography (CBCT) and panorama units and to estimate usefulness of x-ray protective. Rando phantom and glass dosimeters were used for dosimetry. The absorbed doses were measured at 15 organs and 14 remainder from correspond to ICRP 2007 recommendations. The absorbed dose was highest in salivary glands as measured CBCT 2.420mGy, panorama 0.307mGy. Absorbed dose in another organs were high in order of thyroid, brain, skin, esophagus. The effective dose was CBCT 0.100mSv, panorama 0.011mSv and effective dose of panorama was higher than that of CBCT by 10 times. In case of wearing x-ray protective, reducing effective dose of CBCT by 0.066mSv (66%) and panorama by 0.008mSv (72%). Effective dose were reduced by radiological shielding but it needs further optimization studies, where dosimetric data are analyzed in combination with image quality with keep the patients' exposure as low as possible.

• Imaging Science in Dentistry
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• 제31권2호
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• pp.101-107
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• 2001

Purpose: To evaluate the precision of measurements of distances and angle in the cross-sectional views of linear tomogram of panorama and to assess the technique for visualizing the mandibular canal. Methods: Ten dry mandibles were radiographically examined with 3 continuous cross-sectional views of linear tomogram of panorama and 4 continuous computed tomograms. The distance between the superior border of canal and alveolar crest and the bucco-lingual width of alveolar bone at the level of the superior border of canal and the angle between the two lines above were measured. Measurements were performed by radiologist and implantologist group and compared with measurements on computed radiograms of the same areas. Results: The measurements differences for the distance of alveolar bone height between in panorama and in CT showed 0.9 mm±0.6 mm by radiologists and 1.3mm±0.8mm by implantologists. There was no statistically significant difference between two groups' measurements. The differences in measurements for the distance of alveolar bone width between in panorama and in CT showed 0.5mm±0.8mm by radiologists and 2.5mm±1.4 mm by implantologists. There was significant difference (P<0.05) between two groups' measurements. The average bucco-lingual inclination of alveolar bone above mandibular canal was average 95.8° in CT. The difference of measurements between two groups was average 1±0.9°. Three cross-sectional views of panorama could show that the mandibular canal crosses antero-lingually and slopes inferiorly from the posterior segment of the mandible. Conclusions: The measurements in the linear tomogram of panorama by radiologists gave the accurate values of the distances and the angle compared with the values in computed tomograms.

• 대한두개안면성형외과학회지
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• 제12권2호
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• pp.86-92
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• 2011

Purpose: The purpose of this study was to investigate the possibility that a dynamic facial composite flap with sensory and motor nerves could be made available from donor facial composite tissue. Methods: The faces of 3 human cadavers were dissected. The authors studied the donor faces to assess which facial composite model would be most practicable. A "panorama facial flap" was excised from each facial skeleton with circumferential incision of the oral mucosa, lower conjunctiva and endonasal mucosa. In addition, the authors measured the available length of the arterial and venous pedicles, and the sensory nerves. In the recipient, the authors evaluated the time required to anastomose the vessels and nerve coaptations, anchor stitches for donor flaps, and skin stitches for closure. Results: In the panorama facial flap, the available anastomosing vessels were the facial artery and vein. The sensory nerves that required anastomoses were the infraorbital nerve and inferior alveolar nerve. The motor nerve requiring anstomoses was the facial nerve. The vascular pedicle of the panorama facial flap is the facial artery and vein. The longest length was 78 mm and 48 mm respectively. Sensation of the donor facial composite is supplied by the infraorbital nerve and inferior alveolar nerve. Motion of the facial composite is supplied by the facial nerve. Some branches of the facial nerve can be anastomosed, if necessary. Conclusion: The most practical facial composite flap would be a mid and lower face flap, and we proposed a panorama facial flap that is designed to incorporate the mid and lower facial skin with and the unique tissue of the lip. The panorama facial composite flap could be considered as one of the practicable basic models for facial allotransplantation.

• 한국멀티미디어학회논문지
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• 제14권2호
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• pp.201-209
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• 2011

이 논문은 이미지 매칭 알고리즘의 일종인 수정된 SURF(Speeded Up Robust Feature)와 이미지 블렌딩 알고리즘의 일종인 멀티밴드 블렌딩으로 구성된 파노라마 이미지 스티칭 시스템을 제안한다. 이 논문은 처음에 수정된 SURF를 기술하고 SIFT(Scale Invariant Feature Transform)와 비교하여 SURF를 이 시스템에서 채택한 이유에 대하여 논한다. 그리고 멀티밴드 블렌딩에 대하여 기술하고, 이어서 제안된 파노라마 이미지 스티칭 시스템의 구조에 대하여 설명하고 마지막으로 이미지 질과 처리시간에 대한 평가를 한다. 평가결과는 제안된 시스템이 개별 이미지들을 이음매 없이 연결하였으며, 많은 개개의 이미지 데이터에 대해서도 완전한 파노라마 이미지를 생성하였으며 처리 시간도 SIFT보다 빨랐다.

• Smart Structures and Systems
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• 제25권5호
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• pp.631-641
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• 2020

To meet the urgent requirements of safety surveillance from civil engineering management authorities, this study proposes a refined and efficient approach to generate full-field high-resolution panorama of construction sites using camera-amounted UAV (Unmanned Aerial Vehicle). GPS (Global Position System) information extraction for pre-registration, feature points filtering for efficient registration and optimal seaming line seeking for fusion are performed in sequence to form the full-field panorama generation framework. Advantages of the proposed method are as follows. First, GPS information can sort images for pre-registration, avoiding inefficient repeated pairwise calculations and matching. Second, the feature points are filtered according to the characteristics of the construction site images to reduce the amount of calculation. The proposed framework is validated on a road construction site and results demonstrate that it can generate an accurate and high-quality full-site panorama for the safety supervision in a much efficient manner.

• 한국위성정보통신학회논문지
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• 제9권4호
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• pp.32-37
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• 2014

파노라마 영상은 카메라 시야각의 제한을 극복할 수 있으므로 로봇 비전, 스테레오 카메라, 보안 감시 등의 분야에서 효율적으로 연구되고 있다. 파노라마 영상은 사람의 시야각 이상의 넓은 화각을 가진 영상을 구현할 수 있으며 시야각의 현장감을 중심으로 실제로 현장에 있는 듯한 실감 공간을 제공하는 기술이다. 영상에서 기하학적 변화에 강인한 특징점 및 대응점을 검출하고 호모그래피 행렬을 추정하는데 있어서 모든 대응점을 사용하면 연산량이 많아지고 정확한 호모그래피 행렬을 추정하기 어렵다. 따라서 본 논문에서는 전처리 과정에서 입력 영상들의 히스토그램을 비교 분석하여 유사도가 높은 중첩되는 영역을 추정하며 특징점을 검출하기 위해 SURF 알고리즘을 사용하였다. 또한 영상을 입력하는 순서를 해결하여 순서에 제약 없이 영상을 입력하여 파노라마를 생성할 수 있도록 하였다.

• Journal of information and communication convergence engineering
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• 제9권6호
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• pp.780-784
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• 2011

As the popularization and development of 3D display makes common users easy to experience a solid 3D virtual reality, the demand for virtual reality contents are increasing. In this paper, we propose 3D panorama system using vanishing point locationbased depth map generation method. 3D panorama using depthmap stitching gives an effect that makes users feel staying at real place and looking around nearby circumstances. Also, 3D panorama gives free sight point for both nearby object and remote one and provides solid 3D video.

• 전기전자학회논문지
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• 제15권1호
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• pp.10-14
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• 2011

In this paper, we present an efficient hardware architecture of unrolling image mapper of catadioptric omnidirectional imaging systems. The catadioptric omnidirectional imaging systems generate images of 360 degrees of view and need to be transformed into panorama images in rectangular coordinate. In most application, it has to perform the panorama unrolling in real-time and at low-cost, especially for high-resolution images. The proposed hardware architecture adopts a software/hardware cooperative structure and employs several optimization schemes using look-up-table(LUT) of coordinate conversion. To avoid the on-line division operation caused by the coordinate transformation algorithm, the proposed architecture has the LUT which has pre-computed division factors. And then, the amount of memory used by the LUT is reduced to 1/4 by using symmetrical characteristic compared with the conventional architecture. Experimental results show that the proposed hardware architecture achieves an effective real-time performance and lower implementation cost, and it can be applied to other kinds of catadioptric omnidirectional imaging systems.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2020년도 제62차 하계학술대회논문집 28권2호
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• pp.311-314
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• 2020

본 논문에서는 효율적인 웹 파노라마(panorama) 콘텐츠의 효율적인 생성을 위한 에디터를 설계하고 구현한다. 이 에디터는 360° 카메라로 촬영한 파노라마 사진을 활용하여 제작하는 웹 콘텐츠의 주요소인 파노라마 관리, 핫스폿(hotspot) 지정, 추가 및 수정 관리, 파노라마 방향 보정 등의 기능을 구현 할 수 있게 마련하여 누구나 손쉽게 웹 파노라마 콘텐츠를 제작, 관리 할 수 있게 한다. 또한, 파노라마 에디터에 대한 라이브러리와 자료구조를 마련하여 콘텐츠를 개발하고자 하는 초보자나 전문 지식을 가지고 있는 개발자에게도 생산성 향상을 기대할 수 있을 것이다.