• 제목/요약/키워드: Point Preprocessing

검색결과 135건 처리시간 0.026초

A Novel Implementation of Rotation Detection Algorithm using a Polar Representation of Extreme Contour Point based on Sobel Edge

  • Han, Dong-Seok;Kim, Hi-Seok
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제16권6호
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    • pp.800-807
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    • 2016
  • We propose a fast algorithm using Extreme Contour Point (ECP) to detect the angle of rotated images, is implemented by rotation feature of one covered frame image that can be applied to correct the rotated images like in image processing for real time applications, while CORDIC is inefficient to calculate various points like high definition image since it is only possible to detect rotated angle between one point and the other point. The two advantages of this algorithm, namely compatibility to images in preprocessing by using Sobel edge process for pattern recognition. While the other one is its simplicity for rotated angle detection with cyclic shift of two $1{\times}n$ matrix set without complexity in calculation compared with CORDIC algorithm. In ECP, the edge features of the sample image of gray scale were determined using the Sobel Edge Process. Then, it was subjected to binary code conversion of 0 or 1 with circular boundary to constitute the rotation in invariant conditions. The results were extracted to extreme points of the binary image. Its components expressed not just only the features of angle ${\theta}$ but also the square of radius $r^2$ from the origin of the image. The detected angle of this algorithm is limited only to an angle below 10 degrees but it is appropriate for real time application because it can process a 200 degree with an assumption 20 frames per second. ECP algorithm has an O ($n^2$) in Big O notation that improves the execution time about 7 times the performance if CORDIC algorithm is used.

Kinect Depth 카메라를이용한 마우스 커서의 위치 선정에 관한 연구 (A Study On Positioning Of Mouse Cursor Using Kinect Depth Camera)

  • 구봉회;이승호
    • 전기전자학회논문지
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    • 제18권4호
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    • pp.478-484
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    • 2014
  • 본 논문에서는 Kinect Depth 카메라에서 손가락의 방향을 이용한 마우스 커서의 위치 선정에 관한 새로운 방법을 제안한다. 제안하는 방법은 손가락의 방향이 카메라를 향해 있을 경우는 거리변환을 이용한 손의 중점좌표를 이용한다. 손가락의 방향이 카메라를 향해 있지 않을 경우에는 손가락의 끝점 좌표를 이용한다. 손의 중점좌표는 전처리를 거친 영상의 거리변환 결과에서 가장 밝은 픽셀의 좌표를 이용하여 구한다. 손가락의 방향이 카메라를 향해 있을 경우에는 손가락의 끝점 좌표와 손의 중점 좌표 사이의 거리가 가까워지므로 중점좌표를 이용하여, 위치 선정의 정확도를 향상시킬 수 있게 된다. 손가락의 끝점 좌표는 손 영역만을 추출한 영상에서 팔 부분을 제거하여 영상의 중심에서 가장 멀리 떨어져있는 픽셀을 이용하여 구한다. 본 논문에서 제안하는 커서 위치 선정의 정확도를 측정하기 위해 임의의 5개의 기준 좌표를 선정하고 기준 좌표와 측정된 마우스 좌표사이의 오차를 500회 반복하여 측정하여 에러율을 측정한 결과, 평균 11 % 미만의 오차율을 나타내어 제안한 방법의 정확도를 확인할 수가 있었다.

ARM 및 FPGA를 이용한 고속 레이저 삼각측량 시스템 (Fast Laser Triangular Measurement System using ARM and FPGA)

  • 이상문
    • 대한임베디드공학회논문지
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    • 제8권1호
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    • pp.25-29
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    • 2013
  • Recently ARM processor's processing power has been increasing rapidly as it has been applied to consumer electronics products. Because of its computing power and low power consumption, it is used to various embedded systems.( including vision processing systems.) Embedded linux that provides well-made platform and GUI is also a powerful tool for ARM based embedded systems. So short period to develop is one of major advantages to the ARM based embedded system. However, for real-time date processing applications such as an image processing system, ARM needs additional equipments such as FPGA that is suitable to parallel processing applications. In this paper, we developed an embedded system using ARM processor and FPGA. FPGA takes time consuming image preprocessing and numerical algorithms needs floating point arithmetic and user interface are implemented using the ARM processor. Overall processing speed of the system is 60 frames/sec of VGA images.

Multiple Face Segmentation and Tracking Based on Robust Hausdorff Distance Matching

  • Park, Chang-Woo;Kim, Young-Ouk;Sung, Ha-Gyeong
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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    • pp.632-635
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    • 2003
  • This paper describes a system fur tracking multiple faces in an input video sequence using facial convex hull based facial segmentation and robust hausdorff distance. The algorithm adapts skin color reference map in YCbCr color space and hair color reference map in RGB color space for classifying face region. Then, we obtain an initial face model with preprocessing and convex hull. For tracking, this algorithm computes displacement of the point set between frames using a robust hausdorff distance and the best possible displacement is selected. Finally, the initial face model is updated using the displacement. We provide an example to illustrate the proposed tracking algorithm, which efficiently tracks rotating and zooming faces as well as existing multiple faces in video sequences obtained from CCD camera.

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웹 환경에서 벡터 정보를 갖는 래스터 지도 뷰어의 개발 (Developing a Viewer for Raster Map with Vector Information in the Web Environment)

  • 부기동;전일수
    • 한국산업정보학회논문지
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    • 제4권4호
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    • pp.143-148
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    • 1999
  • 본 연구에서는 웹 환경에서 래스터 지도를 벡터 지도처럼 이용할 수 있는 방법을 제안하였으며, 웹 브라우저 내에서 실행되는 전용 래스터 지도 뷰어를 개발하였다. 전처리 과정을 통하여 래스터 지도의 객체에 부여된 좌표들은 벡터 정보로서 사용되며, 래스터 지도 뷰어에서는 각 객체의 좌표와 연결된 속성 데이터베이스를 이용하여 공간분석이 가능하도록 하였다. 개발한 지도 뷰어는 래스터 이미지의 특성을 이용하기 때문에 저렴한 비용으로 웹 GIS를 구축할 수 있고, 공간분석을 위한 컴포넌트의 개발이 훨씬 용이하게 이루어 질 수 있다는 장점이 있다.

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고무타이어 자동분류를 위한 돌출문자 인식 (Recognition of Raised Characters for Automatic Classification of Rubber Tires)

  • 함영국;강민석;정홍규;박래홍;박귀태
    • 전자공학회논문지B
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    • 제31B권4호
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    • pp.77-87
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    • 1994
  • This paper presents recognition of raised alphanumeric markings on rubber tires for their automatic classification. Raised alphanumeric markings on rubber tires have different characteristics as compared to those of printed characters. In the preprocessing step, we first determine the rotation angle using the Hough transform and align markings, then separate each character using vertical and horizontal projections. In the recognition step, we use several features such as width of a character, cross point, partial projection, and distance feature to recognize characters hierarchically. The computer simulation result shows that the proposed system can be successfully applied to the industrial automation of rubber tires classification.

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단면 윤곽선을 이용한 표면의 실시간 3차원 재구성 (Realtime 3D Reconstruction of the Surface on Cross Sectional Contour in CT Image)

  • 구자일;정상봉;민홍기;홍승홍
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1998년도 추계학술대회
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    • pp.189-190
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    • 1998
  • In this paper, we show the realtime 3D reconstruction algorithm with the sliced CT images. The preprocessing is thresholding, labeling, contouring, and extracting dominant point. we reconstruct 3D image with dominant points using dynamic matching technique. The software implemented in Visualc++ 5.0 as a window-based application program.

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Multiple Face Segmentation and Tracking Based on Robust Hausdorff Distance Matching

  • Park, Chang-Woo;Kim, Young-Ouk;Sung, Ha-Gyeong;Park, Mignon
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제3권1호
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    • pp.87-92
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    • 2003
  • This paper describes a system for tracking multiple faces in an input video sequence using facial convex hull based facial segmentation and robust hausdorff distance. The algorithm adapts skin color reference map in YCbCr color space and hair color reference map in RGB color space for classifying face region. Then, we obtain an initial face model with preprocessing and convex hull. For tracking, this algorithm computes displacement of the point set between frames using a robust hausdorff distance and the best possible displacement is selected. Finally, the initial face model is updated using the displacement. We provide an example to illustrate the proposed tracking algorithm, which efficiently tracks rotating and zooming faces as well as existing multiple faces in video sequences obtained from CCD camera.

다척도 지붕에지 검출방법을 이용한 지문영상의 전처리에 대한 연구 (A Study On Preprocessing of Fingerprint Image Using Multi-Scale Roof Edges)

  • 김수겸
    • Journal of Advanced Marine Engineering and Technology
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    • 제29권2호
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    • pp.217-224
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    • 2005
  • A new roof edge detection method based on multi level scales of wavelet function is proposed in this paper roof edge and its direction are obtained in this new methods at one time. Besides. scale characteristics of detecting roof edge is analyzed. And a few new methods on fingerprint image pre-processing are described. A method segmenting foreground/background of fingerprint images is proposed, in which Prior estimation of direction field is not required any more. A segmentation method based on multi-scale roof edges is implemented. and the valid scale range of the method is defined. too. And the method is used to segment ridges and valleys in fingerprint images simultaneously The exact direction fields made up of the direction of each point in ridges can be obtained when detecting ridges exactly based on the roof edge detector, in comparison with the traditional coarse estimation of direction fields. Obviously. it will establish a solid foundation for the sequent fingerprint identification.

Implementation of a Modified SQI for the Preprocessing of Magnetic Flux Leakage Signal

  • Oh, Bok-Jin;Choi, Doo-Hyun
    • Journal of Magnetics
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    • 제18권3호
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    • pp.357-360
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    • 2013
  • A modified SQI method using magnetic leakage flux (MFL) signal for underground gas pipelines' defect detection and characterization is presented in this paper. Raw signals gathered using MFL signals include many unexpected noises and high frequency signals, uneven background signals, signals caused by real defects, etc. The MFL signals of defect free pipelines primarily consist of two kinds of signals, uneven low frequency signals and uncertain high frequency noises. Leakage flux signals caused by defects are added to the case of pipelines having defects. Even though the SQI (Self Quotient Image) is a useful tool to gradually remove the varying backgrounds as well as to characterize the defects, it uses the division and floating point operations. A modified SQI having low computational complexity without time-consuming division operations is presented in this paper. By using defects carved in real pipelines in the pipeline simulation facility (PSF) and real MFL data, the performance of the proposed method is compared with that of the original SQI.