• Title/Summary/Keyword: Otsu 방법

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Musical Score Recognition with SOM and Enhanced ART-1 (SOM과 개선된 ART-1을 이용한 악보 인식)

  • Kim, Kwang-Baek
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.5
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    • pp.1064-1069
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    • 2013
  • In this paper, we propose a Musical Score Recognition with SOM and Enhanced ART-1 Algorithm. First, we apply Hough transform and Otsu's binarization to the original BMP format image and extract notes from separated passages by histogram analysis with removing staff lines. Then extracted musical notes are normalized to same size by SOM algorithm and ART-1 algorithm plays the learning and recognition role. The experiment verifies that the proposed method is quite effective on printed musical score recognition.

Quantitative Assessment Technology of Small Animal Myocardial Infarction PET Image Using Gaussian Mixture Model (다중가우시안혼합모델을 이용한 소동물 심근경색 PET 영상의 정량적 평가 기술)

  • Woo, Sang-Keun;Lee, Yong-Jin;Lee, Won-Ho;Kim, Min-Hwan;Park, Ji-Ae;Kim, Jin-Su;Kim, Jong-Guk;Kang, Joo-Hyun;Ji, Young-Hoon;Choi, Chang-Woon;Lim, Sang-Moo;Kim, Kyeong-Min
    • Progress in Medical Physics
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    • v.22 no.1
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    • pp.42-51
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    • 2011
  • Nuclear medicine images (SPECT, PET) were widely used tool for assessment of myocardial viability and perfusion. However it had difficult to define accurate myocardial infarct region. The purpose of this study was to investigate methodological approach for automatic measurement of rat myocardial infarct size using polar map with adaptive threshold. Rat myocardial infarction model was induced by ligation of the left circumflex artery. PET images were obtained after intravenous injection of 37 MBq $^{18}F$-FDG. After 60 min uptake, each animal was scanned for 20 min with ECG gating. PET data were reconstructed using ordered subset expectation maximization (OSEM) 2D. To automatically make the myocardial contour and generate polar map, we used QGS software (Cedars-Sinai Medical Center). The reference infarct size was defined by infarction area percentage of the total left myocardium using TTC staining. We used three threshold methods (predefined threshold, Otsu and Multi Gaussian mixture model; MGMM). Predefined threshold method was commonly used in other studies. We applied threshold value form 10% to 90% in step of 10%. Otsu algorithm calculated threshold with the maximum between class variance. MGMM method estimated the distribution of image intensity using multiple Gaussian mixture models (MGMM2, ${\cdots}$ MGMM5) and calculated adaptive threshold. The infarct size in polar map was calculated as the percentage of lower threshold area in polar map from the total polar map area. The measured infarct size using different threshold methods was evaluated by comparison with reference infarct size. The mean difference between with polar map defect size by predefined thresholds (20%, 30%, and 40%) and reference infarct size were $7.04{\pm}3.44%$, $3.87{\pm}2.09%$ and $2.15{\pm}2.07%$, respectively. Otsu verse reference infarct size was $3.56{\pm}4.16%$. MGMM methods verse reference infarct size was $2.29{\pm}1.94%$. The predefined threshold (30%) showed the smallest mean difference with reference infarct size. However, MGMM was more accurate than predefined threshold in under 10% reference infarct size case (MGMM: 0.006%, predefined threshold: 0.59%). In this study, we was to evaluate myocardial infarct size in polar map using multiple Gaussian mixture model. MGMM method was provide adaptive threshold in each subject and will be a useful for automatic measurement of infarct size.

Region Segmentation from MR Brain Image Using an Ant Colony Optimization Algorithm (개미 군집 최적화 알고리즘을 이용한 뇌 자기공명 영상의 영역분할)

  • Lee, Myung-Eun;Kim, Soo-Hyung;Lim, Jun-Sik
    • The KIPS Transactions:PartB
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    • v.16B no.3
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    • pp.195-202
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    • 2009
  • In this paper, we propose the regions segmentation method of the white matter and the gray matter for brain MR image by using the ant colony optimization algorithm. Ant Colony Optimization (ACO) is a new meta heuristics algorithm to solve hard combinatorial optimization problem. This algorithm finds the expected pixel for image as the real ant finds the food from nest to food source. Then ants deposit pheromone on the pixels, and the pheromone will affect the motion of next ants. At each iteration step, ants will change their positions in the image according to the transition rule. Finally, we can obtain the segmentation results through analyzing the pheromone distribution in the image. We compared the proposed method with other threshold methods, viz. the Otsu' method, the genetic algorithm, the fuzzy method, and the original ant colony optimization algorithm. From comparison results, the proposed method is more exact than other threshold methods for the segmentation of specific region structures in MR brain image.

Comparative Performance Evaluation of Binarization Methods for Vehicle License Plate (자동차 번호판 이진화 방법에 대한 성능 비교)

  • Kim, Min-Ki
    • The Journal of the Korea Contents Association
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    • v.9 no.8
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    • pp.9-17
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    • 2009
  • License plate recognition is an active research area. but few comparative studies on license plate binarization have been conducted. Many related researchers have experienced similar trial and error for finding an effective binarization method. To reduce this trial and error, this study implemented some binarization methods and quantitatively compared the performance of the methods. The performance evaluation consists of a low level measure and a high level measure, so it can evaluate not only the quality of binarized image itself but also the usefulness of the result. The performance evaluation was separately performed with three groups of images so as to understand the properties of the binarization methods. Experimental results show that the quality of binarization is more dependent on the evenness of illumination than the intensity of illumination. The Otsu's method has acquired the most effective performance in the group of even illumination images and the Niblack's method with parameter correction has shown the best quality in the group of uneven illumination images.

An α-cut Automatic Set based on Fuzzy Binarization Using Fuzzy Logic (퍼지논리를 이용한 α-cut 자동 설정 기반 퍼지 이진화)

  • Lee, Ho Chang;Kim, Kwang Baek;Park, Hyun Jun;Cha, Eui-Young
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.12
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    • pp.2924-2932
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    • 2015
  • Image binarization is a process to divide the image into objects and backgrounds, widely applied to the fields of image analysis and its recognition. In the existing method of binarization, there is some uncertainty when there is insufficient brightness gap between objects and backgrounds in setting threshold. The method of fuzzy binarization has improved the features of objects efficiently. However, since this method sets ${\alpha}$-cut value statically, there remain some problems that important features of objects can be lost during binarization. Therefore, in this paper, we propose a binarization method which does not set ${\alpha}$-cut value statically. The proposed method uses fuzzy membership functions calculated by thresholds of mean, iterative, and Otsu binarization. Experiment results show the proposed method binaries various images with less loss than the existing methods.

Lane Detection based Open-Source Hardware according to Change Lane Conditions (오픈소스 하드웨어 기반 차선검출 기술에 대한 연구)

  • Kim, Jae Sang;Moon, Hae Min;Pan, Sung Bum
    • Smart Media Journal
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    • v.6 no.3
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    • pp.15-20
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    • 2017
  • Recently, the automotive industry has been studied about driver assistance systems for helping drivers to drive their cars easily by integrating them with the IT technology. This study suggests a method of detecting lanes, robust to road condition changes and applicable to lane departure warning and autonomous vehicles mode. The proposed method uses the method of detecting candidate areas by using the Gaussian filter and by determining the Otsu threshold value and edge. Moreover, the proposed method uses lane gradient and width information through the Hough transform to detect lanes. The method uses road lane information detected before to detect dashed lines as well as solid lines, calculates routes in which the lanes will be located in the next frame to draw virtual lanes. The proposed algorithm was identified to be able to detect lanes in both dashed- and solid-line situations, and implement real-time processing where applied to Raspberry Pi 2 which is open source hardware.

Hole Identification Method Based on Template Matching for the Ear-Pins Insertion Automation System (이어핀 삽입 자동화 시스템을 위한 템플릿 매칭 기반 삽입 위치 판별 방법)

  • Baek, Jonghwan;Lee, Jaeyoul;Jung, Myungsoo;Jang, Minwoo;Shin, Dongho;Seo, Kapho;Hong, Sungho
    • KIPS Transactions on Computer and Communication Systems
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    • v.10 no.1
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    • pp.7-14
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    • 2021
  • In jewelry industry, the proportion of labor costs is high. Also, the production time and quality of products are highly varied depending on the workers' capabilities. Therefore, there is a demand from the jewelry industry for automation. The ear pin insertion automation system is the robot automatically inserts the ear pins into the silicone mold, and this automated system require accurate and fast hole detection method. In this paper, we propose optimal binarization method and a template matching method that can be applied in the ear pin insertion automation system. Through the performance test, it was shown that the applied method has an accuracy of 98.5% and 0.5 seconds faster processing speed than the Otsu binarization method. So, this automation system can contribute to cost reduction, work time reduction, and productivity improvement.

Image Processing Algorithm for Crack Detection of Sewer with low resolution (저해상도 하수관거의 균열 탐지를 위한 영상처리 알고리즘)

  • Son, Byung Jik;Jeon, Joon Ryong;Heo, Gwang Hee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.2
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    • pp.590-599
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    • 2017
  • In South Korea, sewage pipeline exploration devices have been developed using high resolution digital cameras of 2 mega-pixels or more. On the other hand, most devices are less than 300 kilo-pixels. Moreover, because 100 kilo-pixels devices are used widely, the environment for image processing is very poor. In this study, very low resolution ($240{\times}320$ = 76,800 pixels) images were adapted when it is difficult to detect cracks. Considering that the images of sewers in South Korea have very low resolution, this study selected low resolution images to be investigated. An automatic crack detection technique was studied using digital image processing technology for low resolution images of sewage pipelines. The authors developed a program to automatically detect cracks as 6 steps based on the MATLAB functions. In this study, the second step covers an algorithm developed to find the optimal threshold value, and the fifth step deals with an algorithm to determine cracks. In step 2, Otsu's threshold for images with a white caption was higher than that for an image without caption. Therefore, the optimal threshold was found by decreasing the Otsu threshold by 0.01 from the beginning. Step 5 presents an algorithm that detects cracks by judging that the length is 10 mm (40 pixels) or more and the width is 1 mm (4 pixels) or more. As a result, the crack detection performance was good despite the very low-resolution images.

Accuracy Assessment of Unsupervised Change Detection Using Automated Threshold Selection Algorithms and KOMPSAT-3A (자동 임계값 추출 알고리즘과 KOMPSAT-3A를 활용한 무감독 변화탐지의 정확도 평가)

  • Lee, Seung-Min;Jeong, Jong-Chul
    • Korean Journal of Remote Sensing
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    • v.36 no.5_2
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    • pp.975-988
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    • 2020
  • Change detection is the process of identifying changes by observing the multi-temporal images at different times, and it is an important technique in remote sensing using satellite images. Among the change detection methods, the unsupervised change detection technique has the advantage of extracting rapidly the change area as a binary image. However, it is difficult to understand the changing pattern of land cover in binary images. This study used grid points generated from seamless digital map to evaluate the satellite image change detection results. The land cover change results were extracted using multi-temporal KOMPSAT-3A (K3A) data taken by Gimje Free Trade Zone and change detection algorithm used Spectral Angle Mapper (SAM). Change detection results were presented as binary images using the methods Otsu, Kittler, Kapur, and Tsai among the automated threshold selection algorithms. To consider the seasonal change of vegetation in the change detection process, we used the threshold of Differenced Normalized Difference Vegetation Index (dNDVI) through the probability density function. The experimental results showed the accuracy of the Otsu and Kapur was the highest at 58.16%, and the accuracy improved to 85.47% when the seasonal effects were removed through dNDVI. The algorithm generated based on this research is considered to be an effective method for accuracy assessment and identifying changes pattern when applied to unsupervised change detection.

A Vehicle License Plate Recognition Using the Haar-like Feature and CLNF Algorithm (Haar-like Feature 및 CLNF 알고리즘을 이용한 차량 번호판 인식)

  • Park, SeungHyun;Cho, Seongwon
    • Smart Media Journal
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    • v.5 no.1
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    • pp.15-23
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    • 2016
  • This paper proposes an effective algorithm of Korean license plate recognition. By applying Haar-like feature and Canny edge detection on a captured vehicle image, it is possible to find a connected rectangular, which is a strong candidate for license plate. The color information of license plate separates plates into white and green. Then, OTSU binary image processing and foreground neighbor pixel propagation algorithm CLNF will be applied to each license plates to reduce noise except numbers and letters. Finally, through labeling, numbers and letters will be extracted from the license plate. Letter and number regions, separated from the plate, pass through mesh method and thinning process for extracting feature vectors by X-Y projection method. The extracted feature vectors are classified using neural networks trained by backpropagation algorithm to execute final recognition process. The experiment results show that the proposed license plate recognition algorithm works effectively.