• Proceedings of the IEEK Conference
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• 2003.07e
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• pp.1775-1778
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• 2003

본 논문에서는 컬러 NTGST (noise-tolerant generalized symmetry transform)를 기초로 하여 부분적인 조명 변화뿐 아니라 그림자 및 잡음이 있는 환경에서도 효과적으로 코너만을 검출할 수 있는 코너 검출자를 제안하였다. 제안한 코너 검출자는 잡음에 둔감한 NTGST를 기초로 하여 코너에 가까울수록, 두 직선 에지가 이루는 각이 작을수록 큰 값이 코너에 누적되도록 하여 코너의 정확한 위치를 검출할 수 있도록 하였다 특히 조명 변화에 둔감한 HSI 색 공간에서 색상 (hue) 성분을 강조하고 채도 (saturation) 및 휘도 (intensity) 성분을 보조적인 정보로 활용함으로써 부분적인 조명 및 그림자의 영향을 줄일 수 있도록 가중조합 벡터 미분 연산자 (weighted combination of vector gradient vector operator)를 제안 적용하여 그림자로 인한 거짓 경계선 및 거짓 코너를 제거할 수 있도록 하였다. 실험을 통하여 제안한 코너 검출 방법이 잡음 및 조명 변화에 둔감하게 효과적으로 코너를 검출함을 확인하였다.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.37 no.2
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• pp.25-32
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• 2000

Digital watermarking has been recently proposed as the means of intellectual property right protection of multimedia data. We present a novel watermarking scheme to hide a copyright information in a digital image. The method Is based on the 2D DWT(Discrete Wavelet Transform) and image statistics. Gaussian and Laplacian noises as the watermarks are added to the large wavelet coefficients at the high and middle frequency bands in the wavelet domain. Experimental results show that the proposed Laplacian watermark is stronger to several common image distortions, such as noises, JPEG coding as different qualities, Gaussian blurring, and edge enhancement.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06b
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• pp.385-387
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• 2006

본 논문에서는 Cubic Convolution 보간 알고리즘을 변형하여 연산량을 감소시키고 에지를 강조하는 보간 알고리즘을 제안한다. 제안된 알고리즘은 디지털 영상의 확대 또는 축소에 필요한 연산량을 줄이기 위해 두가지 방법을 사용하였다. 기존의 Cubic Convolution 알고리즘의 고차항의 가중치 연산을 일차원으로 변환하였다. 인접한 픽셀의 차이값을 사용하여 Bilinear 알고리즘을 제한적으로 적용하였다. 제안된 알고리즘의 화질 평가를 위해 원영상의 확대-후-축소와 축소-후-확대를 하여 RMSE를 사용하였고, 연산량을 평가하기 위해 픽셀별 곱셈기와 덧셈기를 기존의 알고리즘과 비교하였다. 시뮬레이션 결과 기존 Cubic Convolution 알고리즘보다 연산량이 감소하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05b
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• pp.140-143
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• 2004

The mage enhancement of dental On image using wavelet coefficients is presented. The processing is that make gray image from On image by preprocessing, extract high frequency from detail coefficient after acquisition detail coefficient by wavelet transform and emphasize edge appling input image. Experimental results show that enhanced contrast of dental On image, improved mage quality.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.4
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• pp.20-28
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• 2000

The error diffusion algorithm is good for reproducing continuous image to binary image. However the reproduction of edge characteristic is weak in power spectrum analysts of display error. In this paper, an error diffusion method which include pre-filter algorithm for edge characteristic enhancement is proposed Pre-filter algorithm is organized horizontal and vertical directional differential value and weighting function of pre-filter First, it is obtained the horizontal and vertical differential value from the peripheral pixels in original image using $3{\times}3$ Sobel operator Secondly weighting function of pre-filter is composed by function including absolute value and sign of differential value The improved Error diffusion algorithm using pre-filter, present a good result visually which edge characteristic is enhanced. The difference between orignal image and halftoning image is compared with edge-enhanced error diffusion algorithm by measuring the radially averaged power spectrum density.

• Journal of Korea Multimedia Society
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• v.9 no.8
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• pp.963-970
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• 2006

In this paper, we proposed a motion picture processor for using low-cost color super twisted nematic liquid crystal display(CSTN-LCD). The proposed processor apply a new driving scheme using SFP(Subgroup Frame Pattern), so we extends gray scale and eliminates flicker phenomenon. In addition, we apply the BFI (Black Field Insertion) to the design compensated for response time of a LC (Liquid Crystal). We use an edge enhancement and interpolation method to improve image quality of motion picture. The hardware architecture of proposed processor has been implemented and verified on a prototype FPGA board. The proposed method can be used in the display devices such as PDA(Personal Digital Assistants), mobile phone, and PMP(Portable Multimedia Player).

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.1
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• pp.49-58
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• 2012

Buildings become complex and diverse with time. It is difficult to extract individual buildings using only an optical image, because they have similar spectral characteristics to objects such as vegetation and roads. In this study, we propose a method to extract building area and boundary through integrating airborne Light Detection and Ranging(LiDAR) data and aerial images. Firstly, a binary edge map was generated using Edison edge detector after applying Adaptive dynamic range linear stretching radiometric enhancement algorithm to the aerial image. Secondly, building objects on airborne LiDAR data were extracted from normalized Digital Surface Model and aerial image. Then, a temporary building areas were extracted by overlaying the binary edge map and building objects extracted from LiDAR data. Finally, some building boundaries were additionally refined considering positional accuracy between LiDAR data and aerial image. The proposed method was applied to two experimental sites for validation. Through error matrix, F-measure, Jaccard coefficient, Yule coefficient, and Overall accuracy were calculated, and the values had a higher accuracy than 0.85.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.5
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• pp.152-159
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• 2014

In this paper, we introduce a run-length for wavelet coefficients and present a image splicing detection method using the statistical moments for the wavelet run-length. Various pre-processings for the suspicious image are performed to emphasize the discontinuous edges caused by the image splicing. The proposed scheme has the merit that can exploit the various statistical characteristics of the wavelet transform. We extracted up to 72 features, and performed training and testing using SVM(support vector machine). Experimental results showed that the proposed method generates similar detection results compared to the existing methods. In addition, we showed the wavelet domain run-length is useful to detect the spliced image.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.8
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• pp.1782-1790
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• 2011

The goal of image processing is to improve the perceptual aspect and visual appearance of images for human viewers. The objectives of image enhancement vary according to its specific application and an image enhancement techniques used for a specific objective may not be accepted in some other applications. In this paper we review some of conventional enhancement techniques, such as histogram shrink, equalization, and the conservative adaptive contrast enhancement filter. And also, The adaptive contrast enhancement filter has optimized the applied values of variables which is configured rightly the medical image field. In the postprocessing, we used the histogram equalization method. As a result, the inputs which used a medical images has enhanced the edges of a result images which has applied the proposed filter. And also, because of the postprocessing, the image outlines has been lightened.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.5
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• pp.443-450
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• 2014

To fulfill the recent increasement in the public and private demands for various spatial data, the central and local governments started to produce those data. The low-level land cover map has been produced since 2000, yet the production of high-level land covered map has started later in 2010, and recently, a few regions was completed recently. Although many studies have been carried to improve the quality of land that covered in the map, most of them have been focused on the low-level and mid-level classifications. For that reason, the study for high-level classification is still insufficient. Therefore, in this study, we suggested the automatic extraction of land readjustment for paddy land that updated in the mid-level land mapping. At the study, the RapidEye satellite images, which consider efficient to apply in the agricultural field, were used, and the high pass filtering emphasized the outline of paddy field. Also, the binary images of the paddy outlines were generated from the Otsu thresholding. The boundary information of paddy field was extracted from the image-to-map registrations and masking of paddy land cover. Lastly, the snapped edges were linked, as well as the linear features of paddy outlines were extracted by the regional Hough line extraction. The start and end points that were close to each other were linked to complete the paddy field outlines. In fact, the boundary of readjusted paddy fields was able to be extracted efficiently. We could conclude in that this study contributed to the automatic production of a high-level land cover map for paddy fields.