• 한국멀티미디어학회논문지
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• 제24권4호
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• pp.558-568
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• 2021

The digital image to be accepted as legal evidence, it is important to verify the authentication of the digital image. This study proposes a method of authenticating digital images through three steps of comparing the file structure of digital images taken with iPhone, analyzing the encoding information as well as media logs of the iPhone storing the digital images. For the experiment, digital image samples were acquired from nine iPhones through a camera application built into the iPhone. And the characteristics of file structure and media log were compared between digital images generated on the iPhone and digital images edited through a variety of image editing tools. As a result of examining those registered during the digital image creation process, it was confirmed that differences from the original characteristics occurred in file structure and media logs when manipulating digital images on the iPhone, and digital images take with the iPhone. In this way, it shows that it can prove its forensic authentication in iPhone.

• 치과방사선
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• 제29권2호
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• pp.387-396
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• 1999

In dentistry. RadioVisioGraphy was introduced as a first electronic dental x-ray imaging modality in 1989. Thereafter. many types of direct digital radiographic system have been produced in the last decade. They are based either on charge-coupled device(CCD) or on storage phosphor technology. In addition. new types of digital radiographic system using amorphous selenium. image intensifier etc. are under development. Advantages of digital radiographic system are elimination of chemical processing, reduction in radiation dose. image processing, computer storage. electronic transfer of images and so on. Image processing includes image enhancement. image reconstruction. digital subtraction, etc. Especially digital subtraction and reconstruction can be applied in many aspects of clinical practice and research. Electronic transfer of images enables filmless dental hospital and teleradiology/teledentistry system. Since the first image management and communications system(IMACS) for dentomaxillofacial radiology was reported in 1992. IMACS in dental hospital has been increasing. Meanwhile. researches about computer-assisted diagnosis, such as structural analysis of bone trabecular patterns of mandible. feature extraction, automated identification of normal landmarks on cephalometric radiograph and automated image analysis for caries or periodontitis. have been performed actively in the last decade. Further developments in digital radiographic imaging modalities. image transmission system. imaging processing and automated analysis software will change the traditional clinical dental practice in the 21st century.

• 한국지반공학회논문집
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• 제27권7호
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• pp.5-16
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• 2011

고체 역학 및 유체 역학 분야에서 대상 물체의 변형, 변위 및 속도를 측정하기 위하여 디지털 이미지 해석 기법이 개발, 사용되고 있다. 지반 공학에서도 흙을 포함한 지반 구조물의 변형을 관측하기 위하여 Particle Image Velocimetry (PIV)와 Digital Image Correlation (DIC) 기법이 실내 시험 및 모형 시험 등에 적용되기 시작하는 추세이다. 이미지 해석은 시료의 종류 및 크기, 카메라 해상도, 해석 범위, 이미지 해석 조건에 영향을 받으므로, 다양한 조건에서의 정밀도를 평가하여 합리적으로 최적 조건을 결정할 필요가 있다. 본 연구에서는 디지털 이미지 해석 결과에 영향을 미치는 다양한 요소를 정리하였다. 그리고 높은 정확도의 해석 결과를 얻을 수 있는 최적의 이미지 해석 조건을 결정하는 절차를 제안하였으며 최종적으로 제안된 절차의 적용성을 점성토 시료에 대하여 검증하였다.

• 치과방사선
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• 제24권2호
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• pp.439-450
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• 1994

Recently, the digital image was introduced into radiological image. The digital image has the power of contrast enhancement, histogram control, and other digitally enhancement. At the point of the resolution, periapical radiograph is superior to the digital image, but enhanced digital procedure improves the diagnostic ability of the digital image. The purpose of this study was to evaluate the diagnostic ability of artificial proximal caries in conventional radiographs, digital radiographs and enhanced digital radiographs (histogram specification). ROC (Receiver Operating Characteristic) analysis and paired t-test were used for the evaluation of detectability, and following results were acquired: 1. The mean ROC area of conventional radiographs was 0.9274. 2. The mean ROC area of unenhanced digital image was 0.9168. 3. The mean ROC area of enhanced digital image was 0.9339. 4. The diagnostic ability of three imaging methods was not significant difference(p>0.05). So, the digital images had similar diagnostic ability of artificial proximal caries to conventional radiographs. If properly enhanced digital image, it may be superior to conventional radiographs.

• 대한공간정보학회지
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• 제8권2호
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• pp.89-99
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• 2000

수치사진측량시스템(Digital Photogrammetry System)환경 내에서 일어나는 모든 작업은 수치영상을 기본 자료로 이용하게 되므로 수치영상의 품질과 정확도는 수치사진측량의 정확도를 좌우하는 중요한 요소 중에 하나이다. 그림에도 불구하고 현재까지는 수치사진측량 환경의 작업 수행 시 수치영상의 품질이나 정확도에 관한 명확한 기준이 설정되어 있지 않아 자료의 활용성 및 품질을 화보하기 어려운 실정이다. 본 연구에서는 수치사진측량을 이용하여 항공사진영상 데이터베이스를 구축할 경우 선행되어질 항공사진의 수치영상화시 최적해상도를 제시하고자 자동내부표정을 통하여 최적 해상도를 결정하였고, 다음으로 표정해석을 통하여 최적해상도를 검증 하고자 하였다. 그리고 앞서 결정된 최적해상도의 수치영상을 활용하여 정사투영영상이나, 모자이크영상을 제작함으로 그 타탕성을 입증 하고자 하였다.

• 한국지반공학회논문집
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• 제25권12호
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• pp.119-130
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• 2009

흙의 변형을 측정하기 위해 적용되는 이미지 해석 기법으로는 Particle Image Velocimetry(PIV)와 Digital Image Correlation(DIC)가 있으며, 이 기법들이 더욱 널리 활용되기 위해서는 각 기법에 따라 다양한 조건에서 정밀도를 평가하는 연구가 필요하다. 본 연구에서는 이미지 해상도, 변위 및 변형 정도, 픽셀 집합의 크기 및 해석 기법의 다양한 요소를 고려하여 사질토의 변형을 관찰하기에 적합한 최적의 이미지 해석 기법을 제시하고자 한다. 개별요소법(DEM)을 이용하여 구성된 가상의 사질토 이미지를 활용하여 이미지 해석을 행하고 변위를 산정한 후, 개별 요소법의 변위와 비교하였다. 각 영향 요소들이 정확도에 미치는 영향을 분석하였고, 변위 및 변형 정도에 따라 최적의 이미지 해석조건을 제시할 수 있었다.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2004년도 춘계학술발표회논문집
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• pp.203-208
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• 2004

Recently, digital image is increasing greatly practical use degree in several industry fields including construction. And interest about 3D digital image that can express practical object realistically is augmented greatly. In this study, developed 3D digital image generation system based on digital photogrammetry and created 3D digital image for object. And, wished to verify of 3D digital image through comparative analysis with processing result by digital photogrammetry system been using much the latest for acquisition of 3D information. Also, wished to apply to surface information acquisition about rock slope and execute investigation about discontinuity of joint etc. As the result, could created 3D digital image for object using the 3D digital image generation system developing in this study, and acquire surface information about rock slope efficiently.

• 한국실내디자인학회논문집
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• 제14권2호
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• pp.217-224
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• 2005

The lack of objective decisive criteria and the absence of analyzing tools accrued from the experiments on various types developed from space design process makes it difficult to select and execute alternatives for them. As an attempt of coping with these problems, the aims of this study is to establish space analysis' models and to propose possibility of analyzing models by utilizing the technology of image process. It is now under study in the field of artificial intelligence based on the accomplishment of digital images. This study focused on establishment an analysis model based on accomplished digital images and image processing framework. It helps utilize various processing technologies that are currently in use of image processes, and problems of the study can be supplemented through further follow-up studies. Finally, analysis model can be constructed gradually huge design data in the analogue data to the digital image database and be proposed with index in design or evaluation step.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.27-30
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• 2003

In this paper a new approach of digitalized ‘Takbon’ is introduced. By image signal processing, the letters which were written on stones can be deciphered. Epigraphic letter is detected by digital image device, digital camera. The two dimensional digital image is preprocessed because of sensor noise and detective turbulence. Color image is transformed into grey level. The letter image is analyzed in time/frequency domain. By the resultant analysis data decisive functions are calculated. Signal Processing techniques, such as scaling, clipping, digital negative, high/low filter, morphology and so on, provide algorithms that can extract letter from stones.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.292-296
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• 2002

This study has been accomplished as a experimental study for field application of 3D Perspective Image Map creation using Digital Topographical Map and based on the Ortho-Projection Image which is generated from Satellite Overlay Images and the precise Relative Coordinates of longitude, latitude and altitude which is corrected by GCP(Ground Control Point). AS to Contour Lines Map which is created by Coordinate conversion of 1:5,000 Topographical Map, we firstly made Satellite Image Map to substitute for Digital Topographical Map through overlapping the original images on top of each Ortho-Projection Image created and checking the accuracy. In addition to 3D Image Map creation for 3D Terrain analysis of a target district, Slope Gradient Analysis, Aspect Analysis and Terrain Elevation Model generation, multidirectional 3D Image generation by DEM can be carried out through this study. This study is to develop a mapping technology with which we can generate 3D Satellite Images of a target district through the composition of Digital Maps and Facility Blueprint and arbitrarily create 3D Perspective Images of the target district from any view point.