• 자연과학논문집
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• 제4권
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• pp.191-220
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• 1991

Human Visual System(HVS)의 특성과 image의 textural regions의 roughness을 이용하여 image segmentation을 행하여 high compression에서도 고화질을 나타내는 새로운 image coder를 이 논문에서 논한다. 제안된 image coder는 constant segments를 가진 segmentation-based image coding technique의 문제들을 다음과 같은 방법론을 제안함으로써 해결하였다. Image를 HVS으로 보았을 때 degree of roughness에 관하여 textually homogeneous regions으로 segmentation하였다. Fractal dimension을 roughness of textural regions을 측정하기 위하여 사용하였다. Segmentation은 fractal dimension을 thresholding하여 textural regions이 three texture classes로 분류하였다(perceived constant intensity, smooth texture, and rough texture). High compression을 가지는 고질화의 image coder는 각각의 segment boundary와 각각의 texture class에 효율적인 coding technique를 적용 함으로 얻었다.

• Journal of Information Processing Systems
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• 제16권1호
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• pp.49-60
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• 2020

To solve the edge ringing or block effect caused by the partial differential diffusion in image enhancement domain, a new image enhancement algorithm based on bidirectional diffusion, which smooths the flat region or isolated noise region and sharpens the edge region in different types of defect images on aviation composites, is presented. Taking the image pixel's neighborhood intensity and spatial characteristics as the attribute descriptor, the presented bidirectional diffusion model adaptively chooses different diffusion criteria in different defect image regions, which are elaborated are as follows. The forward diffusion is adopted to denoise along the pixel's gradient direction and edge direction in the pixel's smoothing area while the backward diffusion is used to sharpen along the pixel's gradient direction and the forward diffusion is used to smooth along the pixel's edge direction in the pixel's edge region. The comparison experiments were implemented in the delamination, inclusion, channel, shrinkage, blowhole and crack defect images, and the comparison results indicate that our algorithm not only preserves the image feature better but also improves the image contrast more obviously.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2013년도 춘계학술발표대회
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• pp.215-218
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• 2013

In this paper, we proposed a method for enhancement of color images with sky regions. The input image is converted into HSV space and then sky and non-sky regions are separated. For sky region, saturation enhancement is performed for each pixel based on the enhancement factor calculated from the average saturation of its local neighborhood. On the other hand, for the non-sky region, the enhancement is applied only on the luminance value (V) component of the HSV color image, which is performed in two steps. The luminance enhancement, which is also called as dynamic range compression, is carried out using nonlinear transfer function. Again, each pixel is further enhanced for the adjustment of the image contrast depending upon the center pixel and its neighborhood pixel values. At last, the original H and V component image and enhanced S component image for the sky region, and original H and S component image and enhanced V component image for the non-sky region are converted back to RGB image.

• 전자공학회논문지S
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• 제34S권3호
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• pp.84-96
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• 1997

In this paper an efficient morphologica algorithm for reducing gaussian and impulse noise in gray-scale image is presented. Based on the edge information the input image is partitioned into a flat region and an edge region, then different algorithms are selectively applied to each region. in case of impulse noise, MGR (morphologica grayscale reconstruction) algorithm with directional SE (structuring element) is applied to the flat region. For theedge region opening-closing (closing-opening) is used instead of dialation (erosion), so that the remaining noise around large objects can be removed. In case of gaussian noise, 5*5 OCCO(opening closing closing opening) and 3*3 DMF(directional morphological filter ) are used for the flat region and the edgeregion, respectively. In order to remove discontinuity at the edge boundary, the algorithm uses 3*3 OCCO around the edge region to reconstruct the final image. Experimetnal results have shown that the proposed algorithm achieves a high performance in terms of noise removal, detail preservation, and NMSE.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 심포지엄 논문집 정보 및 제어부문
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• pp.57-59
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• 2005

In our study, the automatic tracking algorithm of a human face is proposed by utilizing the thermal properties and 2nd momented geometrical feature of an infrared image. First, the facial candidates are estimated by restricting the certain range of thermal values, and the spurious blobs cleaning algorithm is applied to track the refined facial region in an infrared image.

• 전자공학회논문지S
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• 제34S권7호
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• pp.78-88
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• 1997

A three dimensional-two spatical dimensions plus time-image segmentation is widely used in a very low bit rate image sequence coding because it can solve the region correspondence problem. Mathematical morphology is a very efficient tool for the segmentation because it deals well with geometric features such as size, shape, contrast and connectivity. But if the motion in the image sequence is large in time axis, the conventional 3D morphological segmentation algorithm have difficulty in solving region correspondence problem. To alleviate this problem, we propose the hierarchical image sequence segmentation algorithm that uses the region motion information. Since the motion of a region in previous level affects that in current level uses the previous motion information to increase region correspondence. Simulation result shows improved performance for sequence frames with large motion.

• 한국멀티미디어학회논문지
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• 제7권10호
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• pp.1378-1388
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• 2004

본 논문에서는 웨이블릿 변환(wavelet transform)을 이용하여 저 비트율로 압축된 영상을 복원했을 때 나타나는 화질열화를 개선하는 방법을 제안한다. DCT의 압축에서 화질열화는 블록화 현상(blocking artiiacts)과 잡음(noise) 등이 있었으나 웨이블릿 변환은 블록화 현상이 나타나지 않고 윤곽선(edge) 부근에 링잉현상(ringing artifacts)이 나타나게 되었다. 제안된 방법에서는 윤곽선 부근의 링잉현상이 나타나는 부분과 나타나지 않는 부분을 분류하고 각 영역에 적응적 필터를 적용하여 영상을 개선시켰다. 인간 시각에 거슬리는 윤곽선 영역은 캐니 마스크(Canny mask)를 적용하여 강한 윤곽선 영역을 찾아내고, 또한 주변 영역을 탐색하여 평탄한 영역(fiat region)과 텍스쳐 영역(texture region)으로 분류하고, 각 영역에 맞는 필터 를 적용하게 된다. 실험결과, 링잉현상이 나타나는 저 비트율 압축 영상에서 제안된 방법의 PSNR 값은 0.05db정도 낮아졌지만, 강한 경계 영역과 평탄한 영역의 영상에서는 0.023db정도 높아겼다. 또한 인간 시각의 주관적 관점에서 볼 때 평탄한 영역에서의 링잉현상이 보다 개선된 화질을 보였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.192-194
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• 2003

Since the details in quasi-homogeneous region will be destroyed from the conventional global image enhancement method such as histogram equalization. This defect is caused by the saturation of gray level in equalization process. So the local histogram equalization for each quasi-homogeneous region will be used in order to improve the details in the region itself. To obtain the quasi- homogeneous regions, the original image must be segmented. Here we applied the watershed transform to the interesting image. Since the watershed transform is based on mathematical morphology, therefore, the regions touch can be effectively separated. Hence two adjacent regions which have the similar gray pixels will be split off. The process will be independently applied to three different spectral images. Then three different colors are assigned to each processed image in order to produce a color composite image. By the proposed algorithm, the result image shows the better perception on image details. Therefore, the high efficiency of image classification can be obtained by using this color image.

• 동아시아식생활학회지
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• 제20권5호
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• pp.639-654
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• 2010

This study attempted to research the local food of various regions at a personal level by discovering how food has developed das part of a region's culture base. Discovery of the characteristic story behind the making of a region's characteristic food as local delicacies can inspire self-esteem in the culture, and enhance the real-life image as appropriate to a region, and thereby be made a part of local tourism and thus contributing to the local economy. For this reason, the native foods of the region of Chungcheongnam-do were researched in terms of the cultural sensibilities that inform the unique history of that region. The study was designed so as to aid in understanding food's characteristic value in Chungcheongnam-do and to give a historical representation of Chungcheongnam-do's image by means of storytelling techniques; thus, the local food's character can be presented alongside a story that appeals to the five senses. For this purpose, Chungcheongnam-do's representative native rice table was cast as the 'Hyunchoong rice meal table' - after the figure of admiral Yi Sun Shin of Asan area region, a representative image of Chungcheongnam-do - and 'Choosa rice meal table', after the figure of 'Choosa' Kim Jeong Hee of Yesan region, of which various literary works form a representative image of Chungcheongnam-do. 'Hyunchoong rice meal table' was composed of a health food centered menu which could supply sufficient nutrition as a food ration in times of war or winter shortage, thus providing an image of nutrition and power as appropriate to these situations. Also, to assess the health effectiveness of each rice table, the functionality of the ingredients were investigated as reported in 'Sik-ryo-chan-yo : a dietary treatment' which was published by Soon-Ui Cheon in the Chosun era and by which the foods of the early Chosun era won recognition as being both healthy profitable.

• 전자공학회논문지S
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• 제34S권11호
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• pp.102-113
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• 1997

In this paepr, a new image segmentation method reducing efficiently contour information causing bottleneck problem at segmentatio-based very low bit rate codingis proposed, while preserving objective and subjective quality. It consists of 4-level hierarchical image segmentation based on mathematical morphology and 1-leve region merging structure using contast of two adjacent regions. For two adjacent region pairs at the fourth level included in each region of the thid level, contrast is calculated. Among the pairs of two adjacent regions with less value than threshold, two adjacent regions having the minimum contrast are merged first. After region merging, texture of the merged region is updated. The procedure is performed recursively for all the adjacent region pairs at the fourth level included in each region of the third level. Compared with the previous method, the objective and subjective image qualities are similar. But it reduces 46.65% texture information on the average by decreasing total region number to be tansmitted. Specially, it shows reduction of the 23.95% contour information of the average. Thus, it can improve efficiently the bottleneck problem at segementation-based very low bit rate coding.