• 대한의용생체공학회:의공학회지
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• 제14권1호
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• pp.63-72
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• 1993

In this paper, the effect of background grey levels on the visual perception of target image displayed on CRT monitor has been investigated. The purpose of this study is to investigate the efficacy of CRT monitor as a display medium of image Information especially in medical imaging field. Tllree sets of experiments have been performed in this study : the first was to measure the luminance response of CRT monitor and to find the best fitting equation, and the second was the psychophysical experiment measuring the threshold grey level differences between the target image and the background required for visual discrimination (or various background grey levels, and the third was to develop a visual model that is predictable of the threshold grey level difference measured in the psychophysical experiment. The result of psycophysical experiment shows that the visual perception performance is significantly degraded in the range of grey levels lower than 50, which is turned out due to she low luminance change of CRT monitor in this range while human eye has been adapted lo relatively bright ambient illumination. And it Is also shown in the simulation study using the developed visual model that the dominant factor degrading the visual performance is the reflected light from the monitor surface by ambient light in general illumination condition.

• 한국측량학회지
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• 제29권2호
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• pp.157-164
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• 2011

As high-resolution satellite images have enabled large scale topographic mapping and monitoring on global scale with short revisit time, agile sensor orientation, and large swath width, many countries make effort to secure the satellite image information. In Korea, KOMPSAT-2 (KOrea Multi-Purpose SATellite-2) was launched in July 28 2006 with high specification. These satellites have stereo image acquisition capability for 3D mapping and monitoring. To efficiently handle stereo images such as stereo display and monitoring, the accurate epipolar image generation process is prerequisite. However, the process was highly limited due to complexity in epipolar geometry of pushbroom sensor. Recently, the piecewise approach to generate epipolar images using RPC was developed and tested for in-track IKONOS stereo images. In this paper, the piecewise approach was tested for KOMPSAT-2 across-track stereo images to see how accurately KOMPSAT-2 epipolar images can be generated for 3D geospatial applications. In the experiment, two across-track stereo sets from three KOMPSAT-2 images of different dates were tested using RPC as the sensor model. The test results showed that one-pixel level of y-parallax was achieved for manually measured tie points.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권11호
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• pp.5692-5716
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• 2019

One of the best means to safeguard the confidentiality, security, and privacy of an image within the IoT-Cloud is through encryption. However, looking through encrypted data is a difficult process. Several techniques for searching encrypted data have been devised, but certain security solutions may not be used in IoT-Cloud because such solutions are not lightweight. We propose a lightweight scheme that can perform a content-based search of encrypted images, namely EEIRI. In this scheme, the images are represented using local features. We develop and validate a secure scheme for measuring the Euclidean distance between two descriptor sets. To improve the search efficiency, we employ the k-means clustering technique to construct a searchable tree-based index. Our index construction process ensures the privacy of the stored data and search requests. When compared with more familiar techniques of searching images over plaintexts, EEIRI is considered to be more efficient, demonstrating a higher search cost of 7% and a decrease in search accuracy of 1.7%. Numerous empirical investigations are carried out in relation to real image collections so as to evidence our work.

• 한국컴퓨터정보학회논문지
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• 제4권2호
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• pp.19-26
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• 1999

화상 처리 방법은 최근 다양한 기법을 적용하여 지도 정보 시스템 구축에 대한 요구가 급격히 대두되고 있다. 따라서 본 논문은 이러한 GIS(Geographic Information System) 시스템을 효율적으로 구축하기 위한 방안으로, 기존 지도 도형이나 수 작업에 의해 작성된 도면을 컴퓨터로 스케닝하여 각종 도로 정보 인식 추출하는 방법을 제안하였다. 이러한 화상 정보 인식 방안간으로 많은 알고리듬들이 제시되고 있지만, 실제로 그 활용 면에서, 인식 분석 처리 과정이 매우 복잡함으로 인하여 충분히 반영되지 못하고 있는 한계성을 가지고 있다. 따라서 본 논문은 지도 화상을 스케닝하여 도로 정보를 효율적으로 분리추출하기 위하여 $3{\times}3$ 방향성 구조요소, 즉 수리 형태학적 기법에서 Erosion과 Dilation 그리고 Opening과 Closing, 최적의 Structuring Element를 적용하여, 대상 화상인 지도에서 최적의 도로정보와 문자열간의 특징 분리 추출의 유효성을 검증하고자 한다.

• ETRI Journal
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• 제23권2호
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• pp.41-51
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• 2001

MPEG-7 standardization work has started with the aims of providing fundamental tools for describing multimedia contents. MPEG-7 defines the syntax and semantics of descriptors and description schemes so that they may be used as fundamental tools for multimedia content description. In this paper, we introduce a texture based image description and retrieval method, which is adopted as the homogeneous texture descriptor in the visual part of the MPEG-7 final committee draft. The current MPEG-7 homogeneous texture descriptor consists of the mean, the standard deviation value of an image, energy, and energy deviation values of Fourier transform of the image. These are extracted from partitioned frequency channels based on the human visual system (HVS). For reliable extraction of the texture descriptor, Radon transformation is employed. This is suitable for HVS behavior. We also introduce various matching methods; for example, intensity-invariant, rotation-invariant and/or scale-invariant matching. This technique retrieves relevant texture images when the user gives a querying texture image. In order to show the promising performance of the texture descriptor, we take the experimental results with the MPEG-7 test sets. Experimental results show that the MPEG-7 texture descriptor gives an efficient and effective retrieval rate. Furthermore, it gives fast feature extraction time for constructing the texture descriptor.

• 한국생활과학회지
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• 제18권2호
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• pp.535-545
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• 2009

The purpose of this study is to investigate the effect of earring(nothing, small, medium, large), neckline(round, low), and hairstyle(bound, unbound) on image formation. Sets of stimulus and response scales(7 point semantic) were used as experimental materials. The stimuli were 16 pictures manipulated with the combination of earring, neckline, and hairstyle. The objects of the study were 192 female undergraduates living in Gyeongsangnam-do. The results of this study were as follows. Image factor of the stimulus was composed of 4 different components, concentration of attention, attractiveness, gracefulness, and cuteness. In the concentration of attention, earring and neckline showed independent effect. In the attractiveness, neckline showed independent effect. In the gracefulness, earring and hairstyle showed independent effect. Significant interaction effects of earring and neckline on concentration of attention, attractiveness and gracefulness were found. Interaction effects of neckline and hairstyle on cuteness were found. The study results are highly expected to be used as useful sources in developing total coordination.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권9호
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• pp.3211-3230
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• 2014

Recently, sparse coding has achieved remarkable success in image representation tasks. In practice, the performance of clustering can be significantly improved if limited label information is incorporated into sparse coding. To this end, in this paper, a novel semi-supervised algorithm, called constrained sparse concept coding (CSCC), is proposed for image representation. CSCC considers limited label information into graph embedding as additional hard constraints, and hence obtains embedding results that are consistent with label information and manifold structure information of the original data. Therefore, CSCC can provide a sparse representation which explicitly utilizes the prior knowledge of the data to improve the discriminative power in clustering. Besides, a kernelized version of our proposed CSCC, namely kernel constrained sparse concept coding (KCSCC), is developed to deal with nonlinear data, which leads to more effective clustering performance. The experimental evaluations on the MNIST, PIE and Yale image sets show the effectiveness of our proposed algorithms.

• 대한원격탐사학회지
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• 제22권1호
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• pp.75-85
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• 2006

This paper has dealt with a data fusion for the problem of land-cover classification using multisensor imagery. Dempster-Shafer evidence theory has been employed to combine the information extracted from the multiple data of same site. The Dempster-Shafer's approach has two important advantages for remote sensing application: one is that it enables to consider a compound class which consists of several land-cover types and the other is that the incompleteness of each sensor data due to cloud-cover can be modeled for the fusion process. The image classification based on the Dempster-Shafer theory usually assumes that each sensor is represented by a single channel. The evidential approach to image classification, which utilizes a mass function obtained under the assumption of class-independent beta distribution, has been discussed for the multiple sets of mutichannel data acquired from different sensors. The proposed method has applied to the KOMPSAT-1 EOC panchromatic imagery and LANDSAT ETM+ data, which were acquired over Yongin/Nuengpyung area of Korean peninsula. The experiment has shown that it is greatly effective on the applications in which it is hard to find homogeneous regions represented by a single land-cover type in training process.

• 복식문화연구
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• 제19권2호
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• pp.389-401
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• 2011

Jewelry is not only symbolic meaning of the fortune, but also it completes or redound to fashion style and its image in this modern times which diverse culture live together. The instinct for adornment which is long as human cultures is developed as Artwork genuinely to show effective self-expression that is aesthetic and distinguished. It would be from that it made by using metallic materials. In contemporary fashion, jewelry takes so much importance that it sets the trend. They carry a sensible message that expresses esthetic desire and originality. Among the so many kinds of jewelry, especially the necklace is located beneath the face and linked as a part of fashion, so it frequently has showed in Fashion Collection, We tend to study the effect of that the form, hue and character of materials of necklace that is expressed in fashion collection influence fashion image. The method of this study is comprised with precedent studies and analysis of necklace photos in fashion collection. For the analysis of data, we implement content analysis and statistical analysis using SPAW Statistics 18. As the result, fashion and jewelry effect interactively and share esthetic forms, in the view of total image necklace image is more strong than fashion image. Because the hue and the form of necklace take a great role to make fashion image with the sense of its eyesight, its effective coordination go up the delicate feelings of the fashion. So, it is very effective things that we predict the trend of fashion, then, coordinate with well-matched necklace.

• 정보처리학회논문지B
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• 제19B권2호
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• pp.113-122
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• 2012

스테레오 정합(stereo matching) 기술은 주어진 두 영상에서 동일한 물체의 영상점이 어떤 위치 관계를 가지고 있는지를 결정하는 기술이다. 본 논문에서는 영상 특징점에 대해 스테레오 위치관계를 결정하는 새로운 스테레오 특징점 정합(stereo feature matching) 방법을 제시한다. 제안하는 방법은 주어진 스테레오 영상에서 FAST 추출기를 이용하여 특징점을 추출하고, 특징점 벡터들의 정보들을 내부에 포함하는 특징창(feature window)이라는 공간을 정의하여 스테레오 정합의 성능을 향상한다. 제안하는 방법은 표준 영상에 추출된 특징점들에 대해 특징창을 생성하고, 참조 영상에서 표준 영상의 특징창과 가장 유사한 특징창을 탐색 및 결정한 다음, 결정된 두 개의 특징창 내부의 특징점들의 시차관계는 특징링크(feature link)를 생성하여 시차를 결정한다. 만약, 이 과정에서 시차가 결정되지 않은 특징점들이 있다면, 특징창 내의 결정된 시차 정보를 이용하여 시차 값을 보간한다. 마지막으로, 제안하는 방법의 성능을 검증하기 위해 결과 영상과 정답 영상의 시차를 비교하여 정합 정확성과 수행시간을 비교하였다. 또한, 기존의 특징점 기반 스테레오 정합 방법들과 제안하는 방법의 성능을 비교 및 분석하였다.