• 제목/요약/키워드: Image processing algorithms

검색결과 904건 처리시간 0.024초

Corner outlier 제거를 위한 후처리 기법 (Post-Processing for Reducing Corner Outliers)

  • 홍윤표;전병우
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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    • pp.11-14
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    • 2003
  • In block-based lossy video compression, severe quantization causes discontinuities along block boundaries so that annoying blocking artifacts are visible in decoded video imases. These blocking artifacts significantly decrease the subjective image quality. In order to reduce the blocking artifacts in decoded images, many algorithms have been proposed However studies on so called, corner outliers, have been very limited. Corner outliers make image edges look disconnected from those of neighboring blocks at cross block boundary. In order to solve this problem, we propose a corner outlier detection and compensation algorithm as post-processing in spatial domain The experiment results show that the proposed method provides much improved subjective image quality.

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Stroke Width-Based Contrast Feature for Document Image Binarization

  • Van, Le Thi Khue;Lee, Gueesang
    • Journal of Information Processing Systems
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    • 제10권1호
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    • pp.55-68
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    • 2014
  • Automatic segmentation of foreground text from the background in degraded document images is very much essential for the smooth reading of the document content and recognition tasks by machine. In this paper, we present a novel approach to the binarization of degraded document images. The proposed method uses a new local contrast feature extracted based on the stroke width of text. First, a pre-processing method is carried out for noise removal. Text boundary detection is then performed on the image constructed from the contrast feature. Then local estimation follows to extract text from the background. Finally, a refinement procedure is applied to the binarized image as a post-processing step to improve the quality of the final results. Experiments and comparisons of extracting text from degraded handwriting and machine-printed document image against some well-known binarization algorithms demonstrate the effectiveness of the proposed method.

소형.대용량 Metalized Film Capacitor의 용접 오차 검출 개발 (A Welding Inspection of Small-sized Metalized Film Capacitor with Large Capacity)

  • 정원영;오춘석;유영기;임종설;이서영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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    • pp.135-137
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    • 2004
  • In this study we'll deal with the small-sized metalized film capacitors with large capacity which head have $5mm{\times}5mm{\times}2.5mm$ dimension. The lead wire is used to weld at both sides of capacitors. At that time the position gap between the welding machine and lead wire supplier would cause the welding error. Also, during the tapping processing of metalized film capacitors, the interval error among the capacitors, the length error of lead frame attached at the capacitors, and the straightness distortion of the lead frame could happen. As mentioned, four kinds of error parameters will be measured and analyzed by using the automatic visual inspection system that is implemented with CCD camera, optical parts, background lighting, and image processing algorithms. Finally we are able to achieve success rate above 99% to detect the welding faults of capacitors in the field test.

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디지털 프린팅을 위한 실시간 직물 결점 검출 시스템 (A Real-Time Inspection System for Digital Textile Printing)

  • 김경준;이채정;박윤철;김주용
    • 한국염색가공학회지
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    • 제20권1호
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    • pp.48-56
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    • 2008
  • A real-time inspection system has been developed by combining CCD based image processing algorithm and a standard lighting equipment. The system was tested for defective fabrics showing nozzle contact scratch marks, which are one of the frequently occurring defects. Two algorithms used were compared according to both their processing time and detection rate. First algorithm (algorithm A) was based on morphological image processing such as dilation and opening for effective treatment of defective printing areas while second one (algorithm B) mainly employs well-defined edge detection technique based on canny detector and Zermike moment. It was concluded' that although both algorithms were quite successful, algorithm B showed relatively consistent performance than algorithm A in detecting complex patterns.

통합된 이진화 구조를 가진 복합기용 1-Chip 영상처리 프로세서의 개발 (Single chip multi-function peripheral image processor with unified binarization architecture)

  • 박창대;이을환;김재호
    • 전자공학회논문지S
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    • 제36S권11호
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    • pp.34-43
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    • 1999
  • 본 논문에서는 디지털 복합기에 사용할 수 있는 고속 영상처리 프로세스를 설계 및 구현하였다. 제안된 영상 처리 프로세스는 단일화 된 데이터 경로를 가진 이진화 알고리듬 아키텍쳐를 가진다. 외부 메모리 용량을 최소화하기 위해 화소별 파이프라인 구조를 가지고 있다. 쉐이딩 보정, 감마 보정, 자동이득조절과 같은 전처리 기능을 수행하고 CCD와 CIS를 구동한다. 전처리된 데이터는 확대/축소 과정을 거치고 다양한 이진화 알고리듬에 의해 이진화된다. 내장된 이진화 알고리듬은 단순이진화, 고대역 통과 필터링, 디더링, 오차확산법, 임계값이동 오차확산법이다. 이들 알고리듬의 구현은 임계값 이동 오차확산법에 기반을 두고 동일한 동작을 하는 회로들을 공유하도록 데이터 경로를 설계하였다. 이 구조를 구현함에 의해 제어의 복잡도와 게이트 카운터를 줄일 수 있다.

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센서 네트워크 기반 자율주행 자동차 제어 시스템 설계 및 구현 (Design and Implementation of Sensor Network based Autonomous Vehicle Control System)

  • 장원철;김종면
    • 대한임베디드공학회논문지
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    • 제7권5호
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    • pp.247-253
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    • 2012
  • This paper presents sensor network based autonomous vehicle system using a proposed image processing algorithm. The proposed image processing algorithm consists of pre-processing and five-stage image processing: coordinate calculation, driving area decision, line segment calculation, steeling decision, and acceleration decision. We evaluate the performance of the proposed algorithm on both straight road and curved road. Experimental results indicate that the proposed algorithm works well for autonomous vehicles. However, control accuracy of the proposed algorithm decreases as speed is increasing.

말초혈액영상에서 신경망 모델을 이용한 적혈구의 형태학적 변이 분류 (Morphological Variation Classification of Red Blood Cells using Neural Network Model in the Peripheral Blood Images)

  • 김경수;김판구
    • 한국정보처리학회논문지
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    • 제6권10호
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    • pp.2707-2715
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    • 1999
  • Recently, there have been researches to automate processing and analysing images in the medical field using image processing technique, a fast communication network, and high performance hardware. In this paper, we propose a system to be able to analyze morphological abnormality of red-blood cells for peripheral blood image using image processing techniques. To do this, we segment red-blood cells in the blood image acquired from microscope with CCD camera and then extract UNL fourier features to classify them into 15 classes. We reduce the number of multi-variate features using PCA to construct a more efficient classifier. Our system has the best performance in recognition rate, compared with two other algorithms, LVQ3 and k-NN. So, we show that it can be applied to a pathological guided system.

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Minimum Statistics-Based Noise Power Estimation for Parametric Image Restoration

  • Yoo, Yoonjong;Shin, Jeongho;Paik, Joonki
    • IEIE Transactions on Smart Processing and Computing
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    • 제3권2호
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    • pp.41-51
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    • 2014
  • This paper describes a method to estimate the noise power using the minimum statistics approach, which was originally proposed for audio processing. The proposed minimum statistics-based method separates a noisy image into multiple frequency bands using the three-level discrete wavelet transform. By assuming that the output of the high-pass filter contains both signal detail and noise, the proposed algorithm extracts the region of pure noise from the high frequency band using an appropriate threshold. The region of pure noise, which is free from the signal detail part and the DC component, is well suited for minimum statistics condition, where the noise power can be extracted easily. The proposed algorithm reduces the computational load significantly through the use of a simple processing architecture without iteration with an estimation accuracy greater than 90% for strong noise at 0 to 40dB SNR of the input image. Furthermore, the well restored image can be obtained using the estimated noise power information in parametric image restoration algorithms, such as the classical parametric Wiener or ForWaRD image restoration filters. The experimental results show that the proposed algorithm can estimate the noise power accurately, and is particularly suitable for fast, low-cost image restoration or enhancement applications.

컴퓨터 기하학을 위한 병렬계산 (Parallel Computing For Computational Geometry)

  • 오승준
    • 전자통신동향분석
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    • 제4권1호
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    • pp.93-117
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    • 1989
  • Computational Geometry is concerned with the design and analysis of computational algorithms which solve geometry problems. Geometry problems have a large number of applications areas such as pattern recognition, image processing, computer graphics, VLSI design and statistics since they involve inherently geometric problems for which efficient algorithms have to be developed. Several parallel algorithms, based on various parallel computation models, have been proposed for solving geometric problems. We review the current status of the parallel algorithms in computational geometry.

A Survey on Content Aware Image Resizing Methods

  • Garg, Ankit;Negi, Ashish
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권7호
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    • pp.2997-3017
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    • 2020
  • With the advancement in the field of image processing, images are being processed using various image processing algorithms. Nowadays, many efficient content-aware image resizing techniques are being used to safeguard the prominent regions and to generate better results that are visually appealing and pleasing while resizing. Advancements in the new display device with varying screen size demands the development of efficient image resizing algorithm. This paper presents a survey on various image retargeting methods, comparison of image retargeting results based on performance, and also exposes the main challenges in image retargeting such as content preservation of important regions, distortion minimization, and improving the efficiency of image retargeting methods. After reviewing literature from researchers it is suggested that the use of the single operator in image retargeting such as scaling, cropping, seam carving, and warping is not sufficient for obtaining satisfactory results, hence it is essential to combine multiple image retargeting operators. This survey is useful for the researchers interested in content-aware image retargeting.