• Title/Summary/Keyword: 그레이 레벨

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An Effective Measurement Algorithm for the Cornea in Automatic Refracto-Keratometer (자동 시각 굴절력 곡률계에서의 효과적인 각막 측정 알고리즘)

  • Seong, Won;Lee, Kyeong-Min;Han, Ki-Sun;Park, Jong-Won
    • Proceedings of the Korea Information Processing Society Conference
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    • 2002.11a
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    • pp.691-694
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    • 2002
  • 본 논문은 자동 시각 굴절력 곡률계의 전자 부문에 연동될 곡률 측정 알고리즘을 소개한다. 만약 자동화된 시스템이 광학계로부터 나오는 영상을 이용하여 내부 처리를 거친 후 정확한 시각 측정치를 검사자에게 알려줄 수 있다면 잘못 측정되는 측정 횟수를 크게 줄일 수 있을 것이다. 본 연구는 형태학적 필터링(morphological filtering)과 그레이-레벨의 신호 강조(signal enhance) 기술들을 이용하여 자동 시각 굴절력 곡률계에 연동될 각막 곡률과 굴절력 측정 알고리즘을 개발하였다. 알고리즘에서는 광학계로부터 도출된 링 모양 광원의 화상을 처리하기 위해서 새로운 방법을 사용하는 대신에 구면 굴절력 측정을 위해서 6 개의 점으로 구성된 화상을 처리하는 방식으로 변형 적용시킨다. 이 때 링의 띠를 6 개의 덩어리 점으로 변형하는 과정만을 제외하면 구면 굴절력 영상을 처리하는 방식과 같게 된다. 이는 알고리즘의 간결화와 측정 시간을 줄이는 효과를 얻게 된다. 그리하여 본 각막 측정 알고리즘은 정확한 측정값 도출이 어려운 시각 영상에 적용되어 효과적으로 오차를 줄임으로써 보다 효율적인 각막 측정을 가능하게 하였다.

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A Study on Korean Printed Character Type Classification And Nonlinear Grapheme Segmentation (한글 인쇄체 문자의 형식 분류 및 비선형적 자소 분리에 관한 연구)

  • Park Yong-Min;Kim Do-Hyeon;Cha Eui-Young
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2006.05a
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    • pp.784-787
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    • 2006
  • In this paper, we propose a method for nonlinear grapheme segmentation in Korean printed character type classification. The characters are subdivided into six types based on character type information. The feature vector is consist of mesh features, vertical projection features and horizontal projection features which are extracted from gray-level images. We classify characters into 6 types using Back propagation. Character segmentation regions are determined based on character type information. Then, an optimal nonlinear grapheme segmentation path is found using multi-stage graph search algorithm. As the result, a proposed methodology is proper to classify character type and to find nonlinear char segmentation paths.

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Heterogeneous Face Recognition Using Texture feature descriptors (텍스처 기술자들을 이용한 이질적 얼굴 인식 시스템)

  • Bae, Han Byeol;Lee, Sangyoun
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.14 no.3
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    • pp.208-214
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    • 2021
  • Recently, much of the intelligent security scenario and criminal investigation demands for matching photo and non-photo. Existing face recognition system can not sufficiently guarantee these needs. In this paper, we propose an algorithm to improve the performance of heterogeneous face recognition systems by reducing the different modality between sketches and photos of the same person. The proposed algorithm extracts each image's texture features through texture descriptors (gray level co-occurrence matrix, multiscale local binary pattern), and based on this, generates a transformation matrix through eigenfeature regularization and extraction techniques. The score value calculated between the vectors generated in this way finally recognizes the identity of the sketch image through the score normalization methods.

Real Time Monocular Navigation using VFH (단일 카메라를 이용한 VFH 기반의 실시간 주행 기술 개발)

  • Jo, Jang-won;Ju, Jin Sun;Ko, Eunjeong;Kim, Eun Yi
    • Proceedings of the Korea Information Processing Society Conference
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    • 2010.04a
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    • pp.348-351
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    • 2010
  • 본 논문에서는 단일 카메라로부터 주어진 영상을 실시간으로 장애물과 비장애물 영역으로 분류한 후 VFH 를 이용하여 안전한 경로를 선정하는 실시간 주행 시스템을 개발한다. 제안된 시스템은 점유 그리드맵 생성기와 VFH 기반의 선정기로 구성된다. 점유 그리드맵 생성기는 입력된 $320{\times}240$ 영상의 색조와 명도 정보를 이용하여 실시간으로 배경과 장애물 영역을 분류하고, 이를 바탕으로 위험도에 따라 10 개의 그레이 레벨을 가지는 $32{\times}24$ 의 점유 그리드맵을 생성한다. VFH를 이용하여 폴라 히스토그램을 작성한 후 밀도가 낮은 곳으로 주행 경로를 결정 한다. 제안된 기술의 효율성을 증명하기 위하여 다양한 형태의 장애물을 포함하는 실내 및 실외 환경에서 평가하였으며 센서 기반의 그 결과는 기존의 센서기반의 주행시스템과 비교 되었다. 그 결과 제안된 시스템은 88%의 정확도를 보였으며, 기존의 시스템보다 실시간으로 빠르고 안전한 주행을 수행할 수 있음이 증명되었다.

Saturation Compensating Method by Embedding Pseudo-Random Code in Wavelet Packet Based Colorization (웨이블릿 패킷 기반의 컬러화 알고리즘에서 슈도랜덤코드 삽입을 이용한 채도 보상 방법)

  • Ko, Kyung-Woo;Jang, In-Su;Kyung, Wang-Jun;Ha, Yeong-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.4
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    • pp.20-27
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    • 2010
  • This paper proposes a saturation compensating method by embedding pseudo-random code information in wavelet packet based colorization algorithm. In the color-to-gray process, an input RGB image is converted into YCbCr images, and a 2-level wavelet packet transform is applied to the Y image. And then, color components of CbCr are embedded into two sub-bands including minimum amount of energy on the Y image. At this time, in order to compensate the color saturations of the recovered color image during the printing and scanning process, the maximum and minimum values of CbCr components of an original image are also embedded into the diagonal-diagonal sub-band by a form of pseudo-random code. This pseudo-random code has the maximum and minimum values of an original CbCr components, and is expressed by the number of white pixels. In the gray-to-color process, saturations of the recovered color image are compensated using the ratio of the original CbCr values to the extracted CbCr values. Through the experiments, we can confirm that the proposed method improves color saturations in the recovered color images by the comparison of color difference and PSNR values.

Blind Watermarking by Using Circular Input Method and Binary Image (이진영상과 Circular Input 방식을 이용한 Blind 워터마킹)

  • Kim Tae-Ho;Kim Young-Hee;Jin Kyo-Hong;Ko Bong-Jin;Park Mu-Hun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.8
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    • pp.1407-1413
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    • 2006
  • The field of medical images has been digitalized as the development of computer and the digitalization of the medical instruments. As a result it causes a lot of problems such as an illegal copy related to medical images and property right of the medical images. Therefore, digital watermarking is used for discrimination whether the data are modified or not. It is also used to protect both the property right of medical images and the private life of many patients. The proposed theories, the Non-blind and the Blind method, have two problems. One is needed an original image and the other is using a gaussian watermarking. This paper proposes the new Blind Watermarking using binary images in order to easily recognize the results of watermark. This algorism is described that an watermark of a binary image is wavelet-transformed, and then a transformed watermark is inserted in medium-band of frequency domains of original image by the Circular Input method. This method don't have any loss when image didn't have any attack. As a result Watermark can be perfectly extracted by using this algorithm. And Maximam PSNR value is improved 3.35dB. This algorithm will be improved by using gray level image and color image.

Copyright Protection for Fire Video Images using an Effective Watermarking Method (효과적인 워터마킹 기법을 사용한 화재 비디오 영상의 저작권 보호)

  • Nguyen, Truc;Kim, Jong-Myon
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.8
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    • pp.579-588
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    • 2013
  • This paper proposes an effective watermarking approach for copyright protection of fire video images. The proposed watermarking approach efficiently utilizes the inherent characteristics of fire data with respect to color and texture by using a gray level co-occurrence matrix (GLCM) and fuzzy c-means (FCM) clustering. GLCM is used to generate a texture feature dataset by computing energy and homogeneity properties for each candidate fire image block. FCM is used to segment color of the fire image and to select fire texture blocks for embedding watermarks. Each selected block is then decomposed into a one-level wavelet structure with four subbands [LL, LH, HL, HH] using a discrete wavelet transform (DWT), and LH subband coefficients with a gain factor are selected for embedding watermark, where the visibility of the image does not affect. Experimental results show that the proposed watermarking approach achieves about 48 dB of high peak-signal-to-noise ratio (PSNR) and 1.6 to 2.0 of low M-singular value decomposition (M-SVD) values. In addition, the proposed approach outperforms conventional image watermarking approach in terms of normalized correlation (NC) values against several image processing attacks including noise addition, filtering, cropping, and JPEG compression.

The Multi Knowledge-based Image Retrieval Technology for An Automobile Head Lamp Retrieval (자동차 전조등 검색을 위한 다중지식기반의 영상검색 기법)

  • 이병일;손병환;홍성욱;손성건;최흥국
    • Journal of the Institute of Convergence Signal Processing
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    • v.3 no.3
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    • pp.27-35
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    • 2002
  • A knowledge-based image retrieval technique is image searching methods using some features from the queried image. The materials in this study are automobile head lamps. The input data is composed of characters and images which have various pattern. The numbers, special symbols, and general letters are under the category of the character. The image informations are made up of the distribution of pixel data, statistical analysis, and state of pattern which are useful for the knowledge data. In this paper, we implemented a retrieval system for the scientific crime detection at traffic accident using the proposed multi knowledge-based image retrieval technique. The values for the multi knowledge-based image features were extracted from color and gray scale each. With this 22 features, we improved the retrieval efficiency about the color information and pattern information. Visual basic, crystal report and MS access DB were used for this application. We anticipate the efficient scientific detection for the traffic accident and the tracking of suspicious vehicle.

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An Experimental Study on the Flow Characteristics around Wedge Type Structure by Slamming (슬래밍에 의한 쐐기형 구조물 주위의 유동특성에 관한 실험적 연구)

  • Oh, Seung-Jin;Cho, Dae-Hwan
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.19 no.2
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    • pp.213-218
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    • 2013
  • This paper presents are experimental investigation to figure out slamming impact pressure and flow characteristics of a wedge type structure in free fall. The flow field has been obtained by 2-frame grey level cross correlation PIV(Particle Image Velocimetry) method, the impact presure of free fall structure by a pressure acquisition system apply to Dewetron system. The angles between a model and the free surface are adapted $15^{\circ}$, $25^{\circ}$, $35^{\circ}$ and $45^{\circ}$ respectively. Velocity field of water exit has higher better than water entry. The impact pressure under the bottom of the model ha been appeared higher values at 15 degrees than 45 degrees, and also at P1.

Object Segmentation for Image Transmission Services and Facial Characteristic Detection based on Knowledge (화상전송 서비스를 위한 객체 분할 및 지식 기반 얼굴 특징 검출)

  • Lim, Chun-Hwan;Yang, Hong-Young
    • Journal of the Korean Institute of Telematics and Electronics T
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    • v.36T no.3
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    • pp.26-31
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    • 1999
  • In this paper, we propose a facial characteristic detection algorithm based on knowledge and object segmentation method for image communication. In this algorithm, under the condition of the same lumination and distance from the fixed video camera to human face, we capture input images of 256 $\times$ 256 of gray scale 256 level and then remove the noise using the Gaussian filter. Two images are captured with a video camera, One contains the human face; the other contains only background region without including a face. And then we get a differential image between two images. After removing noise of the differential image by eroding End dilating, divide background image into a facial image. We separate eyes, ears, a nose and a mouth after searching the edge component in the facial image. From simulation results, we have verified the efficiency of the Proposed algorithm.

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