• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권10호
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• pp.5112-5129
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• 2019

Image enhancement is a challenging problem in the field of image processing, especially low-light color images enhancement. This paper proposed a robust and comprehensive enhancement method based several points. First, the idea of bright channel is introduced to estimate the illumination map which is used to attain the enhancing result with Retinex model, and the color constancy is keep as well. Second, in order eliminate the illumination offsets wrongly estimated, morphological closing operation is used to modify the initial estimating illumination. Furthermore, in order to avoid fabricating edges, enlarged noises and over-smoothed visual features appearing in enhancing result, a multi-scale closing operation is used. At last, in order to avoiding the haloes and artifacts presented in enhancing result caused by gradient information lost in previous step, guided filtering is introduced to deal with previous result with guided image is initial bright channel. The proposed method can get good illumination map, and attain very effective enhancing results, including dark area is enhanced with more visual features, color natural and constancy, avoiding artifacts and over-enhanced, and eliminating Incorrect light offsets.

• 대한가정학회지
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• 제29권4호
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• pp.45-64
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• 1991

Each of us has personal and unique "Mental Images" of environment that are the results of a two-way process between an observer and his environment. By understanding of people's image on their physical settings through cognitive maps, congruent with their design environment. In this context, this study is to fine out the characteristics of the resident's image in apartment housing that are modern housing. This paper is theoretically based on Appleyard's cognitive maps types, Lynch's the components of image, Harrison and Howard's image enhancing factors and Applyard's image enhancing factors of buildings. For the purpose of this study, two-instruments were used. One was sketch mapping, that told of visual aspects of cognitive map. Another was verbal questionnaire, which was composed of nonvisual aspects of image components and image enhancing factors. For the methods of research analysis, Percentage, Frequency, and Chi-square test were used. The results of this study are as follows. Firstly, as for the types of cognitive maps, the rate of sequential maps and spatial maps are nearly same. Secondly, as for the components of images, landmarks and districts are significant elements in apartment housing, and edges, nodes and paths are rare element. Thirdly, with regard to image enhancing factors, landscaping is shown to be most effective at landmarks and districts. And finally, in examing the differences of images between various social groups, significant variables are years of living and housing size. Age and income are the next. In this study of image, we can learn about manner in which individuals come to see, understand, and cope with the environment at a personal level. So, user-oriented approach is useful in environmental design, and particularly, it is useful in the apartment housing of the future life space.

• Journal of information and communication convergence engineering
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• 제15권2호
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• pp.131-136
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• 2017

Chest X-ray image cannot be focused in the same manner as optical lenses and the resultant image generally tends to be slightly blurred. Therefore, appropriate methods to improve the quality of chest X-ray image have been studied in this paper. As the frequency domain filters work well for slight blurring and moderate levels of additive noises, we propose an algorithm that is particularly suitable for enhancing chest image. First, the chest image using Gaussian high pass filter and the optimal high frequency emphasis filter shows improvements in the edges and contrast of the flat areas. Second, as compared to using histogram equalization where each pixel of chest image is characterized by a loss of detail and much noises, in using fuzzy logic, each pixel of chest image shows the detail preservation and little noise.

• 한국공작기계학회논문집
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• 제16권5호
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• pp.122-128
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• 2007

The electric part of thermal SEM(Scanning Electron Microscopy) consists of high voltage generation, lens control, and image processing. Several methodologies for enhancing SEM image are addressed and those results are verified through analyses and experiments. The controller employes a DSP(Digital Signal Processing), making the system more flexible and convenient than the classical analogue based controller. In some parts based the analog circuit, there are inevitable sources of noise and image distortion. The experimental investigation is provided along with analytical proof to enhance the SEM image.

• 한국측량학회지
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• 제17권2호
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• pp.167-176
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• 1999

각종 영상매체와 수치영상처리 기술이 발전함에 따라 수치영상을 이용한 대상물의 정량적 또는 정성적 분석에 관한 연구가 활발히 진행되고 있다. 그러나 높은 정확도의 영상해석에 있어 고해상도의 영상획득 시스템에 대한 의존도가 매우 높은 실정이며 이들은 고가의 장비라는 문제점을 안고 있다. 본 연구에서는 저가의 영상획득 시스템에 의해 획득한 다중영상을 강화ㆍ분석하여 최적의 강화조건을 도출하고 이를 적용하여 3차원 정확도 분석을 실시하였다. 저해상도의 원시영상과 최적의 조건에 의해 강화한 영상을 이용하여 평균 3차원 위치오차를 분석한 결과, 강화영상은 원시영상에 비해 10％정도 향상된 정확도를 보였다.

• 한국환경복원기술학회지
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• 제9권6호
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• pp.1-12
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• 2006

Remote sensing cannot provide a direct measurement of vegetation index (VI) but it can provide a reasonably good estimate of vegetation index, defined as the ratio of satellite bands. The monitoring of vegetation in nearby urban regions is made difficult by the low spatial resolution and temporal resolution image captures. In this study, enhancing spatial resolution method is adapted as to improve a low spatial resolution. Recent studies have successfully estimated normalized difference vegetation index (NDVI) using improved resolution method such as from the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard EOS Terra satellite. Image enhancing spatial resolution is an important tool in remote sensing, as many Earth observation satellites provide both high-resolution and low-resolution multi-spectral images. Examples of enhancement of a MODIS multi-spectral image and a MODIS NDVI image of Cheongju using a Landsat TM high-resolution multi-spectral image are presented. The results are compared with that of the IHS technique is presented for enhancing spatial resolution of multi-spectral bands using a higher resolution data set. To provide a continuous monitoring capability for NDVI, in situ measurements of NDVI from paddy field was carried out in 2004 for comparison with remotely sensed MODIS data. We compare and discuss NDVI estimates from MODIS sensors and in-situ spectroradiometer data over Ochang plain region. These results indicate that the MODIS NDVI is underestimated by approximately 50%.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제12권8호
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• pp.243-252
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• 2023

위성 이미지는 토지 표면 조사에서 매우 중요하다. 따라서 위성에서 지상국으로 이미지를 전송하기 위해 다양한 방법을 사용하고 있다. 그러나 전송 시스템의 품질 저하로 인해 이미지는 왜곡에 취약하고 올바른 데이터를 제공하지 못하고 있다. 그러한 이미지의 세그먼트 결과는 토지 표면 데이터를 올바르게 분류할 수 없다. 본 논문에서는 위성영상에 대한 자동인코더 기반의 영상 전처리 방법을 제안한다. 실험결과 사전 향상 기술을 사용하여 세그멘테이션 결과도 크게 향상될 수 있음을 보여주었다. 또한 본 논문에서 적용한 항공 이미지 향상기법은 토지 자원의 정확한 평가에 이바지할 수 있음을 확인하였다.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 2007년도 춘계학술대회
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• pp.53-57
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• 2007

This paper presents the practice of multitexturing in the Internet for enhancing the image quality of 3D contents, where the attributes of objects such as textures are dynamically changed. We explain the empirical results of realizing the X3D nodes related with multitexturing in the recent X3D viewers, and discuss the directions for upgrading X3D viewers that satisfy the user requirements and the advanced graphics accelerators.

• 한국멀티미디어학회논문지
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• 제22권9호
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• pp.983-991
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• 2019

Histogram equalization method is a popular contrast enhancement technique. However, there are some drawbacks, namely, over-enhancement, under-enhancement, structure information loss, and noise amplification. In this paper, we propose an edge-enhancing histogram equalization algorithm while suppressing over-enhancement simultaneously. Firstly, over-enhancement is suppressed by clipping a transfer function, then, edge enhancement is achieved by using guided image filter. Experiments are carried out to evaluate the performance of the various HE algorithms. As a result, both qualitative and quantitative assessment showed that the proposed algorithm successfully suppressed over-enhancement while enhancing edges.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2002년도 추계종합학술대회
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• pp.222-225
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• 2002

본 논문은 의료영상 워터마킹에 웨이블릿 패킷을 적용한 연구이다. 웨이블릿 패킷기법을 적용하여 저주파 대역에서 고주파 대역까지 손실을 최소화하므로 의료영상의 분해능을 향상시킨다. 비교분석 실험결과 PSNR은 0.1dB 이상 향상되었고 내구성 평가에서 압축률 60%에서 PSNR이 28dB 이상 얻었다. 결과적으로 의료영상의 화질이 향상되었으며 고의적인 영상왜곡 및 변형 등의 외부 공격에 대해 내구성을 유지하는 결과를 얻었다.