• Title/Summary/Keyword: Edge histogram detector

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Wavelet-Based Edge Detection Using Local Histogram Analysis in Images (영상에서 웨이블렛 기반 로컬 히스토그램 분석을 이용한 에지검출)

  • Park, Min-Joon;Kwon, Min-Jun;Kim, Gi-Hun;Shim, Han-Seul;Kim, Dong-Wook;Lim, Dong-Hoon
    • The Korean Journal of Applied Statistics
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    • v.24 no.2
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    • pp.359-371
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    • 2011
  • Edge detection in images is an important step in image segmentation and object recognition as preprocessing for image processing. This paper presents a new edge detection using local histogram analysis based on wavelet transform. In this work, the wavelet transform uses three components (horizontal, vertical and diagonal) to find the magnitude of the gradient vector, instead of the conventional approach in which tw components are used. We compare the magnitude of the gradient vector with the threshold that is obtained from a local histogram analysis to conclude that an edge is present or not. Some experimental results for our edge detector with a Sobel, Canny, Scale Multiplication, and Mallat edge detectors on sample images are given and the performances of these edge detectors are compared in terms of quantitative and qualitative measures. Our detector performs better than the other wavelet-based detectors such as Scale Multiplication and Mallat detectors. Our edge detector also preserves a good performance even if the Sobel and Canny detector are sharply low when the images are highly corrupted.

Video Scene Detection using Shot Clustering based on Visual Features (시각적 특징을 기반한 샷 클러스터링을 통한 비디오 씬 탐지 기법)

  • Shin, Dong-Wook;Kim, Tae-Hwan;Choi, Joong-Min
    • Journal of Intelligence and Information Systems
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    • v.18 no.2
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    • pp.47-60
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    • 2012
  • Video data comes in the form of the unstructured and the complex structure. As the importance of efficient management and retrieval for video data increases, studies on the video parsing based on the visual features contained in the video contents are researched to reconstruct video data as the meaningful structure. The early studies on video parsing are focused on splitting video data into shots, but detecting the shot boundary defined with the physical boundary does not cosider the semantic association of video data. Recently, studies on structuralizing video shots having the semantic association to the video scene defined with the semantic boundary by utilizing clustering methods are actively progressed. Previous studies on detecting the video scene try to detect video scenes by utilizing clustering algorithms based on the similarity measure between video shots mainly depended on color features. However, the correct identification of a video shot or scene and the detection of the gradual transitions such as dissolve, fade and wipe are difficult because color features of video data contain a noise and are abruptly changed due to the intervention of an unexpected object. In this paper, to solve these problems, we propose the Scene Detector by using Color histogram, corner Edge and Object color histogram (SDCEO) that clusters similar shots organizing same event based on visual features including the color histogram, the corner edge and the object color histogram to detect video scenes. The SDCEO is worthy of notice in a sense that it uses the edge feature with the color feature, and as a result, it effectively detects the gradual transitions as well as the abrupt transitions. The SDCEO consists of the Shot Bound Identifier and the Video Scene Detector. The Shot Bound Identifier is comprised of the Color Histogram Analysis step and the Corner Edge Analysis step. In the Color Histogram Analysis step, SDCEO uses the color histogram feature to organizing shot boundaries. The color histogram, recording the percentage of each quantized color among all pixels in a frame, are chosen for their good performance, as also reported in other work of content-based image and video analysis. To organize shot boundaries, SDCEO joins associated sequential frames into shot boundaries by measuring the similarity of the color histogram between frames. In the Corner Edge Analysis step, SDCEO identifies the final shot boundaries by using the corner edge feature. SDCEO detect associated shot boundaries comparing the corner edge feature between the last frame of previous shot boundary and the first frame of next shot boundary. In the Key-frame Extraction step, SDCEO compares each frame with all frames and measures the similarity by using histogram euclidean distance, and then select the frame the most similar with all frames contained in same shot boundary as the key-frame. Video Scene Detector clusters associated shots organizing same event by utilizing the hierarchical agglomerative clustering method based on the visual features including the color histogram and the object color histogram. After detecting video scenes, SDCEO organizes final video scene by repetitive clustering until the simiarity distance between shot boundaries less than the threshold h. In this paper, we construct the prototype of SDCEO and experiments are carried out with the baseline data that are manually constructed, and the experimental results that the precision of shot boundary detection is 93.3% and the precision of video scene detection is 83.3% are satisfactory.

Text Region Extraction using Pattern Histogram of Character-Edge Map in Natural Images (문자-에지 맵의 패턴 히스토그램을 이용한 자연이미지에서의 텍스트 영역 추출)

  • Park, Jong-Cheon;Hwang, Dong-Guk;Lee, Woo-Ram;Kwon, Kyo-Hyun;Jun, Byoung-Min
    • Proceedings of the KAIS Fall Conference
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    • 2006.11a
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    • pp.220-224
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    • 2006
  • The text to be included in the natural images has many important information in the natural image. Therefore, if we can extract the text in natural images, It can be applied to many important applications. In this paper, we propose a text region extraction method using pattern histogram of character-edge map. We extract the edges with the Canny edge detector and creates 16 kind of edge map from an extracted edges. And then we make a character-edge map of 8 kinds that have a character feature with a combination of an edge map. We extract text region using 8 kinds of character-edge map and 16 kind of edge map. Verification of text candidate region uses analysis of a character-edge map pattern histogram and structural feature of text region. The method to propose experimented with various kind of the natural images. The proposed approach extracted text region from a natural images to have been composed of a complex background, various letters, various text colors effectively.

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Segmentation of Lung and Lung Lobes in EBT Medical Images (EBT 의료 영상에서 폐 영역 추출 및 폐엽 분할)

  • 김영희;이성기
    • Journal of KIISE:Software and Applications
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    • v.31 no.3
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    • pp.276-292
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    • 2004
  • In this paper. we present methods that extract lung regions from chest EBT(electron beam tomography) images then segment the extracted lung region into lung lobes. We use histogram based thresholding and mathematical morphology for extracting lung regions. For detecting pulmonary fissures, we use edge detector and knowledge-based search method. We suggest this edge detector, which uses adaptive filter scale, to work very well for real edge and insensitive for edge by noise. Our experiments showed about 95% accuracy or higher in extracting lung regions and about 5 pixel distance error in detecting pulmonary fissures.

Pedestrian Detection Algorithm using a Gabor Filter Bank (Gabor Filter Bank를 이용한 보행자 검출 알고리즘)

  • Lee, Sewon;Jang, Jin-Won;Baek, Kwang-Ryul
    • Journal of Institute of Control, Robotics and Systems
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    • v.20 no.9
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    • pp.930-935
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    • 2014
  • A Gabor filter is a linear filter used for edge detectionas frequency and orientation representations of Gabor filters are similar to those of the human visual system. In this thesis, we propose a pedestrian detection algorithm using a Gabor filter bank. In order to extract the features of the pedestrian, we use various image processing algorithms and data structure algorithms. First, color image segmentation is performed to consider the information of the RGB color space. Second, histogram equalization is performed to enhance the brightness of the input images. Third, convolution is performed between a Gabor filter bank and the enhanced images. Fourth, statistical values are calculated by using the integral image (summed area table) method. The calculated statistical values are used for the feature matrix of the pedestrian area. To evaluate the proposed algorithm, the INRIA pedestrian database and SVM (Support Vector Machine) are used, and we compare the proposed algorithm and the HOG (Histogram of Oriented Gradient) pedestrian detector, presentlyreferred to as the methodology of pedestrian detection algorithm. The experimental results show that the proposed algorithm is more accurate compared to the HOG pedestrian detector.

Content-Based Image Retrieval Algorithm Using HAQ Algorithm and Moment-Based Feature (HAQ 알고리즘과 Moment 기반 특징을 이용한 내용 기반 영상 검색 알고리즘)

  • 김대일;강대성
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.4
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    • pp.113-120
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    • 2004
  • In this paper, we propose an efficient feature extraction and image retrieval algorithm for content-based retrieval method. First, we extract the object using Gaussian edge detector for input image which is key frames of MPEG video and extract the object features that are location feature, distributed dimension feature and invariant moments feature. Next, we extract the characteristic color feature using the proposed HAQ(Histogram Analysis md Quantization) algorithm. Finally, we implement an retrieval of four features in sequence with the proposed matching method for query image which is a shot frame except the key frames of MPEG video. The purpose of this paper is to propose the novel content-based image retrieval algerian which retrieves the key frame in the shot boundary of MPEG video belonging to the scene requested by user. The experimental results show an efficient retrieval for 836 sample images in 10 music videos using the proposed algorithm.

Development of a Fruit Sorting System using Statistical Image Processing (통계적 영상처리를 이용한 과일 선별시스템 개발)

  • 임동훈
    • The Korean Journal of Applied Statistics
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    • v.16 no.1
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    • pp.129-140
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    • 2003
  • This study was to develop a fruit sorting system using statistical image processing. Histogram was used to compare fruit colors to standard fruit color and edge detector using Wilcoxon test was used to calculate an accurate geometrical characteristics of fruit including perimeter, area, major axis and minor axis length and roundness. The experimental result obtained from using our system for sorting apples was presented.

Deblurring Algorithm for Vehicle Image Processing Using Sigma Variation of Bilateral Filter (Bilateral 필터의 Sigma 편차를 이용한 차량 영상 Deblur 알고리즘)

  • Son, Hwi-Gon;Kim, Hi-Seok
    • Journal of IKEEE
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    • v.19 no.2
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    • pp.148-154
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    • 2015
  • Automotive electronics system must alarm accurately in every moment. In order to apply vehicle's image recognition algorithms, it is necessary to preprocess the system quickly. In this paper, blurred image correction method that utilizes histogram equalization and bilateral filter using deviation for driver assist system's image processing is proposed. It forms 5-stage processes namely scaler, equalization, modified noise filter, blur decision and edge detector. Using the extracted proper, values in bilateral filter for driving environment occurred driver assist system, the proposed algorithm is much faster processing time compare to the previous methods in blurred within 10 pixel. Results of experiment which are run time and experimental PSNR results using MATLAB is obtained and verified that our proposed algorithm is more faster performance compare with the existing methods.

Implementation of Intelligent Image Surveillance System based Context (컨텍스트 기반의 지능형 영상 감시 시스템 구현에 관한 연구)

  • Moon, Sung-Ryong;Shin, Seong
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.3
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    • pp.11-22
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    • 2010
  • This paper is a study on implementation of intelligent image surveillance system using context information and supplements temporal-spatial constraint, the weak point in which it is hard to process it in real time. In this paper, we propose scene analysis algorithm which can be processed in real time in various environments at low resolution video(320*240) comprised of 30 frames per second. The proposed algorithm gets rid of background and meaningless frame among continuous frames. And, this paper uses wavelet transform and edge histogram to detect shot boundary. Next, representative key-frame in shot boundary is selected by key-frame selection parameter and edge histogram, mathematical morphology are used to detect only motion region. We define each four basic contexts in accordance with angles of feature points by applying vertical and horizontal ratio for the motion region of detected object. These are standing, laying, seating and walking. Finally, we carry out scene analysis by defining simple context model composed with general context and emergency context through estimating each context's connection status and configure a system in order to check real time processing possibility. The proposed system shows the performance of 92.5% in terms of recognition rate for a video of low resolution and processing speed is 0.74 second in average per frame, so that we can check real time processing is possible.

A Study on Enhancing the Performance of Detecting Lip Feature Points for Facial Expression Recognition Based on AAM (AAM 기반 얼굴 표정 인식을 위한 입술 특징점 검출 성능 향상 연구)

  • Han, Eun-Jung;Kang, Byung-Jun;Park, Kang-Ryoung
    • The KIPS Transactions:PartB
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    • v.16B no.4
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    • pp.299-308
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    • 2009
  • AAM(Active Appearance Model) is an algorithm to extract face feature points with statistical models of shape and texture information based on PCA(Principal Component Analysis). This method is widely used for face recognition, face modeling and expression recognition. However, the detection performance of AAM algorithm is sensitive to initial value and the AAM method has the problem that detection error is increased when an input image is quite different from training data. Especially, the algorithm shows high accuracy in case of closed lips but the detection error is increased in case of opened lips and deformed lips according to the facial expression of user. To solve these problems, we propose the improved AAM algorithm using lip feature points which is extracted based on a new lip detection algorithm. In this paper, we select a searching region based on the face feature points which are detected by AAM algorithm. And lip corner points are extracted by using Canny edge detection and histogram projection method in the selected searching region. Then, lip region is accurately detected by combining color and edge information of lip in the searching region which is adjusted based on the position of the detected lip corners. Based on that, the accuracy and processing speed of lip detection are improved. Experimental results showed that the RMS(Root Mean Square) error of the proposed method was reduced as much as 4.21 pixels compared to that only using AAM algorithm.