• Title/Summary/Keyword: step edge

Search Result 378, Processing Time 0.03 seconds

Automated Silhouette Extraction Method for Generating a Blueprint from 3D Scan Data of Cultural Asset (문화재의 3D 스캔 데이터로부터 도면을 생성하기 위한 자동화된 실루엣 추출 방법)

  • Jung, Jung-Il;Cho, Jin-Soo;WhangBo, Tae-Keun
    • The Journal of the Korea Contents Association
    • /
    • v.8 no.12
    • /
    • pp.10-19
    • /
    • 2008
  • In this paper, we propose an automated silhouette extraction method that can effectively extract inner-patterns and silhouettes from 3D scan data of cultural asset. First of all, after creating the edge list of 3D vector data, we decide contour edge and crease edge according to viewpoint. In the next step, after extracting surface silhouette by investigating the vector variation of adjacent faces in crease edge, we finally extract the contour silhouette and surface silhouette for generating the blueprint of cultural asset. To evaluate the performance of the proposed silhouette extraction method, we performed experiments of silhouette extraction using a traditional tile model, a car model and a stone monument model. Comparing with the conventional threshold-based silhouette extraction method, the proposed method extracted more distinct and clear surface silhouettes and inner-patterns by effectively removing meaningless edges, such as noise.

Learning of Rules for Edge Detection of Image using Fuzzy Classifier System (퍼지 분류가 시스템을 이용한 영상의 에지 검출 규칙 학습)

  • 정치선;반창봉;심귀보
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.10 no.3
    • /
    • pp.252-259
    • /
    • 2000
  • In this paper, we propose a Fuzzy Classifier System(FCS) to find a set of fuzzy rules which can carry out the edge detection of a image. The FCS is based on the fuzzy logic system combined with machine learning. Therefore the antecedent and consequent of a classifier in FCS are the same as those of a fuzzy rule. There are two different approaches, Michigan and Pittsburgh approaches, to acquire appropriate fuzzy rules by evolutionary computation. In this paper, we use the Michigan style in which a single fuzzy if-then rule is coded as an individual. Also the FCS employs the Genetic Algorithms to generate new rules and modify rules when performance of the system needs to be improved. The proposed method is evaluated by applying it to the edge detection of a gray-level image that is a pre-processing step of the computer vision. the differences of average gray-level of the each vertical/horizontal arrays of neighborhood pixels are represented into fuzzy sets, and then the center pixel is decided whether it is edge pixel or not using fuzzy if-then rules. We compare the resulting image with a conventional edge image obtained by the other edge detection method such as Sobel edge detection.

  • PDF

Design of Sigma Filter in DCT Domain and its application (DCT영역에서의 시그마 필터설계와 응용)

  • Kim, Myoung-Ho;Eom, Min-Young;Choe, Yoon-Sik
    • Proceedings of the KIEE Conference
    • /
    • 2004.11c
    • /
    • pp.178-180
    • /
    • 2004
  • In this work, we propose new method of sigma filtering for efficient filtering and preserving edge regions in DCT Domain. In block-based image compression technique, the image is first divided into non-overlapping $8{\times}8$ blocks. Then, the two-dimensional DCT is computed for each $8{\times}8$ block. Once the DCT coefficients are obtained, they are quantized using a specific quantization table. Quantization of the DCT coefficients is a lossy process, and in this step, noise is added. In this work, we combine IDCT matrix and filter matrix to a new matrix to simplify filtering process to remove noise after IDCT in spatial domain, for each $8{\times}8$ DCT coefficient block, we determine whether this block is edge or homogeneous region. If this block is edge region, we divide this $8{\times}8$ block into four $4{\times}4$ sub-blocks, and do filtering process for sub-blocks which is homogeneous region. By this process, we can remove blocking artifacts efficiently preserving edge regions at the same time.

  • PDF

A motion-adaptive de-interlacing method using an efficient spatial and temporal interpolation (효율적인 시공간 보간을 통한 움직임 기반의 디인터레이싱 기법)

  • Lee, Seong-Gyu;Lee, Dong-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.38 no.5
    • /
    • pp.556-566
    • /
    • 2001
  • This paper proposes a motion-adaptive de-interlacing algorithm based on EBMF(Edge Based Median Filter) and AMPDF(Adaptive Minimum Pixel Difference Fillet). To compensate 'motion missing'error, which is an important factor in motion-adaptive methods, we used AMPDF which estimates an accurate value using different thresholds after classifying the input image to 4 classes. To efficiently interpolate the moving diagonal edge, we also used EBMF which selects a candidate pixel according to the edge information. Finally, we, to increase the performance, adopted an adaptive interpolation after classifying the input image to moving region, stationary region, and boundary region. Simulation results showed that the proposed method provides better performance than the existing methods.

  • PDF

Edge-based Method for Human Detection in an Image (영상 내 사람의 검출을 위한 에지 기반 방법)

  • Do, Yongtae;Ban, Jonghee
    • Journal of Sensor Science and Technology
    • /
    • v.25 no.4
    • /
    • pp.285-290
    • /
    • 2016
  • Human sensing is an important but challenging technology. Unlike other methods for sensing humans, a vision sensor has many advantages, and there has been active research in automatic human detection in camera images. The combination of Histogram of Oriented Gradients (HOG) and Support Vector Machine (SVM) is currently one of the most successful methods in vision-based human detection. However, extracting HOG features from an image is computer intensive, and it is thus hard to employ the HOG method in real-time processing applications. This paper describes an efficient solution to this speed problem of the HOG method. Our method obtains edge information of an image and finds candidate regions where humans very likely exist based on the distribution pattern of the detected edge points. The HOG features are then extracted only from the candidate image regions. Since complex HOG processing is adaptively done by the guidance of the simpler edge detection step, human detection can be performed quickly. Experimental results show that the proposed method is effective in various images.

Automated Lineament Extraction and Edge Linking Using Mask Processing and Hough Transform.

  • Choi, Sung-Won;Shin, Jin-Soo;Chi, Kwang-Hoon;So, Chil-Sup
    • Proceedings of the KSRS Conference
    • /
    • 1999.11a
    • /
    • pp.411-420
    • /
    • 1999
  • In geology, lineament features have been used to identify geological events, and many of scientists have been developed the algorithm that can be applied with the computer to recognize the lineaments. We choose several edge detection filter, line detection filters and Hough transform to detect an edge, line, and to vectorize the extracted lineament features, respectively. firstly the edge detection filter using a first-order derivative is applied to the original image In this step, rough lineament image is created Secondly, line detection filter is used to refine the previous image for further processing, where the wrong detected lines are, to some extents, excluded by using the variance of the pixel values that is composed of each line Thirdly, the thinning process is carried out to control the thickness of the line. At last, we use the Hough transform to convert the raster image to the vector one. A Landsat image is selected to extract lineament features. The result shows the lineament well regardless of directions. However, the degree of extraction of linear feature depends on the values of parameters and patterns of filters, therefore the development of new filter and the reduction of the number of parameter are required for the further study.

  • PDF

No-reference objective quality assessment of image using blur and blocking metric (블러링과 블록킹 수치를 이용한 영상의 무기준법 객관적 화질 평가)

  • Jeong, Tae-Uk;Kim, Young-Hie;Lee, Chul-Hee
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.46 no.3
    • /
    • pp.96-104
    • /
    • 2009
  • In this paper, we propose a no-reference objective Quality assessment metrics of image. The blockiness and blurring of edge areas which are sensitive to the human visual system are modeled as step functions. Blocking and blur metrics are obtained by estimating local visibility of blockiness and edge width, For the blocking metric, horizontal and vertical blocking lines are first determined by accumulating weighted differences of adjacent pixels and then the local visibility of blockiness at the intersection of blocking lines is obtained from the total difference of amplitudes of the 2-D step function which is modelled as a blocking region. The blurred input image is first re-blurred by a Gaussian blur kernel and an edge mask image is generated. In edge blocks, the local edge width is calculated from four directional projections (horizontal, vertical and two diagonal directions) using local extrema positions. In addition, the kurtosis and SSIM are used to compute the blur metric. The final no-reference objective metric is computed after those values are combined using an appropriate function. Experimental results show that the proposed objective metrics are highly correlated to the subjective data.

Reconstruction from Feature Points of Face through Fuzzy C-Means Clustering Algorithm with Gabor Wavelets (FCM 군집화 알고리즘에 의한 얼굴의 특징점에서 Gabor 웨이브렛을 이용한 복원)

  • 신영숙;이수용;이일병;정찬섭
    • Korean Journal of Cognitive Science
    • /
    • v.11 no.2
    • /
    • pp.53-58
    • /
    • 2000
  • This paper reconstructs local region of a facial expression image from extracted feature points of facial expression image using FCM(Fuzzy C-Meang) clustering algorithm with Gabor wavelets. The feature extraction in a face is two steps. In the first step, we accomplish the edge extraction of main components of face using average value of 2-D Gabor wavelets coefficient histogram of image and in the next step, extract final feature points from the extracted edge information using FCM clustering algorithm. This study presents that the principal components of facial expression images can be reconstructed with only a few feature points extracted from FCM clustering algorithm. It can also be applied to objects recognition as well as facial expressions recognition.

  • PDF

Oxygen Annealing Effect of SrTiO$_3$ Single Crystal Substrate Damaged by Ar$^+$ Ion Milling (Ar 이온 밀링으로 손상된 단결정 SrTiO$_3$ 기판의 산소 열처리 효과)

  • Choi, Hee-Seok;Hwang, Yun-Seok;Kim, Jin-Tae;Lee, Doon-Hoon;Lee, Soon-Gul;Park, Yong-Ki;Park, Jong-Chul
    • 한국초전도학회:학술대회논문집
    • /
    • v.9
    • /
    • pp.87-90
    • /
    • 1999
  • We have studied the annealing effects of 570 (SrTiO$_3$) single crystal substrate and the I-V properties of step-edge junctions after Ar ion milling. YBa$_2Cu_3O_7$ (YBCO) thin films are fabricated on the substrates by using pulsed laser deposition (PLD) and photolithography. The surface of Ar ion milled substrate was characterized with atomic force microscope (AFM) and scanning electron microscope (SEM) images. After the substrate was damaged by milling, the critical current density of YBCO thin films deposited on the substrate was lowered. The annealing of the damaged substrate at about 1000 $^{\circ}C$ recovered the critical current density to that before the milling. Futhermore the annealing helped junction formation due to high quality film and increased the yield rate for the fabrication of high quality step-edge junction.

  • PDF