• Title/Summary/Keyword: $X^2$ Histogram

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Image Recognition Based on Nonlinear Equalization and Multidimensional Intensity Variation (비선형 평활화와 다차원의 명암변화에 기반을 둔 영상인식)

  • Cho, Yong-Hyun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.24 no.5
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    • pp.504-511
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    • 2014
  • This paper presents a hybrid recognition method, which is based on the nonlinear histogram equalization and the multidimensional intensity variation of an images. The nonlinear histogram equalization based on a adaptively modified function is applied to improve the quality by adjusting the brightness of the image. The multidimensional intensity variation by considering the a extent of 4-step changes in brightness between the adjacent pixels is also applied to reflect accurately the attributes of image. The statistical correlation that is measured by the normalized cross-correlation(NCC) coefficient, is applied to comprehensively measure the similarity between the images. The NCC is considered by the intensity variation of each 2-direction(x-axis and y-axis) image. The proposed method has been applied to the problem for recognizing the 50-face images of 40*40 pixels. The experimental results show that the proposed method has a superior recognition performances to the method without performing the histogram equalization, or the linear histogram equalization, respectively.

Aesthetic Measure of Video Image ($X^2$ 히스토그램을 이용한 수면 측정 및 수면의 질 발전)

  • Shin, Kwang-Seong;Shin, Seong-Yoon;Rhee, Yang-Won
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.10a
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    • pp.153-156
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    • 2011
  • 수면은 인간에게서 중요한 생리 현상이며, 인간은 일생의 삼분의 일 정도를 잠을 자면서 보낸다고 한다. 본 논문에서는 이러한 수면을 이루는 환경을 개선하기 위하여 수면을 측정하고 수면의 질 발전 방향을 모색한다. 수면 측정을 위하여 $X^2$ 히스토그램을 이용한 장면 전환 검출 방법을 이용한다. $X^2$ 히스토그램 방법은 통계학적 장면 전환 검출 방법의 하나로서 다른 히스토그램 방법보다 성능이 우수하기 때문에 많은 연구에서 사용된다. 그리고 수면의 질을 발전시키기 위하여 피곤한 정도, 음주의 정도, 그리고 공복의 정도를 입력하여 각 상황별 뒤척임을 추출한다.

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Intensity Modulated Radiation Therapy of Brain Tumor

  • Kim, Sung-Kyu;Kim, Myung-Se
    • Proceedings of the Korean Society of Medical Physics Conference
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    • 2002.09a
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    • pp.61-64
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    • 2002
  • As intensity modulated radiation therapy compared with conventional radiation therapy, tumor target dose increased and normal tissues and critical organs dose reduced. In brain tumor, treatment planning of intensity modulated radiation therapy was practiced in 4MV, 6MV, 15MV X-ray energy. In these X-ray energy, was considered the dose distribution and dose volume histogram. As 4MV X-ray compared with 6MV and 15MV, maximum dose of right optic-nerve increased 10.1 %, 8.4%. Right eye increased 5.2%, 2.7%. And left optic-nerve, left eye, optic chiasm and brainstem incrased 1.7% - 5.2%. Even though maximum dose of PTV and these critical organs show different from 1.7% - 10.1% according to X-ray energies, these are a piont dose. Therefore in brain tumor, treatment planning of intensity modulated radiation therapy in 9 treatment field showed no relation with energy dependency.

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The Obstacle Avoidance Algorithm of Mobile Robot using Line Histogram Intensity (Line Histogram Intensity를 이용한 이동로봇의 장애물 회피 알고리즘)

  • 류한성;최중경;구본민;박무열;방만식
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.6 no.8
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    • pp.1365-1373
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    • 2002
  • In this paper, we present two types of vision algorithm that mobile robot has CCD camera. for obstacle avoidance. This is simple algorithm that compare with grey level from input images. Also, The mobile robot depend on image processing and move command from PC host. we has been studied self controlled mobile robot system with CCD camera. This system consists of digital signal processor, step motor, RF module and CCD camera. we used wireless RF module for movable command transmitting between robot and host PC. This robot go straight until recognize obstacle from input image that preprocessed by edge detection, converting, thresholding. And it could avoid the obstacle when recognize obstacle by line histogram intensity. Host PC measurement wave from various line histogram each 20 pixel. This histogram is (x, y) value of pixel. For example, first line histogram intensity wave from (0, 0) to (0, 197) and last wave from (280, 0) to (2n, 197. So we find uniform wave region and nonuniform wave region. The period of uniform wave is obstacle region. we guess that algorithm is very useful about moving robot for obstacle avoidance.

Crosswalk Detection using Feature Vectors in Road Images (특징 벡터를 이용한 도로영상의 횡단보도 검출)

  • Lee, Geun-mo;Park, Soon-Yong
    • The Journal of Korea Robotics Society
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    • v.12 no.2
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    • pp.217-227
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    • 2017
  • Crosswalk detection is an important part of the Pedestrian Protection System in autonomous vehicles. Different methods of crosswalk detection have been introduced so far using crosswalk edge features, the distance between crosswalk blocks, laser scanning, Hough Transformation, and Fourier Transformation. However, most of these methods failed to detect crosswalks accurately, when they are damaged, faded away or partly occluded. Furthermore, these methods face difficulties when applying on real road environment where there are lot of vehicles. In this paper, we solve this problem by first using a region based binarization technique and x-axis histogram to detect the candidate crosswalk areas. Then, we apply Support Vector Machine (SVM) based classification method to decide whether the candidate areas contain a crosswalk or not. Experiment results prove that our method can detect crosswalks in different environment conditions with higher recognition rate even they are faded away or partly occluded.

Extraction of Waterline from X-band Satellite SAR Images (X-밴드 위성 SAR 영상을 이용한 수위선 탐지)

  • Lee, Kyung-Yup;Kim, Youn-Soo
    • Aerospace Engineering and Technology
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    • v.10 no.2
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    • pp.163-169
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    • 2011
  • This paper introduces a method about water line detection using SAR image. The method includes pre-processing of the SAR image with the threshold of the histogram to recognize the boundary between the water and the landmass area. Finally we applied the image differentiation to detect the water line in the SAR image. The TerraSAR-X and the Cosmo-SkyMed images, which are the high spatial resolution X-band SAR data, are used for the evaluation of our algorithm. The accuracy is verified over the stream line in urban area with the result from the Cosmo-SkyMed.

New Shot Boundary Detection Method Using Normalization (정규화를 이용한 새로운 샷 경계 검출 방법)

  • Shin, Seong-Yoon;Baik, Seong-Eun;Pyo, Seong-Bae;Rhee, Yang-Won
    • KSCI Review
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    • v.15 no.1
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    • pp.197-201
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    • 2007
  • 비디오 분할은 샷 경계 검출이라고도 하는데, 비디오를 계층적이고 구조적인 형태로 표현하기 위하여 영상, 문자, 오디오와 같은 매체 속에 포함되어 있는 내용들을 특징별로 분석하여 계층별로 분류하는 작업을 말한다. 본 논문에서는 카메라와 객체의 모션에 보다 강건하고 보다 정확한 결과를 산출하여 충분한 공간 정보를 가지는 지역적 $X^2$-히스토그램 비교 방법을 이용하여 샷 경계를 검출한다. 또한 영상처리에서 영상의 명암 값 향상을 위하여 사용되는 로그함수와 상수를 변형하여 차이 값에 적용하는 정규화 방법을 제시한다. 그리고 샷 경계 검출 알고리즘을 제시하여 일반적인 샷과 갑작스런 샷의 특징을 기반으로 검출한다.

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An Optimal Method to Improve the Visual Quality of Medical Images

  • Shin, Choong-ho;Jung, Chai-yeoung
    • Journal of Integrative Natural Science
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    • v.8 no.2
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    • pp.141-144
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    • 2015
  • As the visual quality of X-ray images is a critical reference for the accuracy of the clinical diagnosis, the methods to improve the quality of X-ray images have been investigated. Among many existing methods, using frequency domain filter is a very powerful method to improve the visual quality of images. In this paper, the inherent noises of the input images are suppressed by adding the Laplacian image to the subjected image. The medical X-ray images using the optimal high pass filter has shown improved edges. Further, the optimal high frequency emphasis filter has shown the improved contrast of flat areas by using the result image from the optimal high pass filter. Also the resulting images of the global contrast have improved by the histogram equalization. As a result, the proposed methods have shown enhanced contrast and edges of the images with noise canceling effect.

A Comparative Study of Image Quality and Radiation Dose according to Variable Added Filter and Radiation Exposure in Diagnostic X-Ray Radiography (진단용 X-선 촬영시 부가 필터 및 노출의 변화에 따른 피폭선량 및 영상 화질 비교 연구)

  • Choi, Nam-Gil;Seong, Ho-Jin;Jeon, Joo-Seop;Kim, Youn-Hyun;Seong, Dong-Ook
    • Journal of Radiation Protection and Research
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    • v.37 no.1
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    • pp.25-34
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    • 2012
  • To know which parameters were acceptable for achieving lowest radiation exposure to the patients and highest image quality at the diagnostic X-ray radiography, we measured the patient radiation dose and image quality in transmitted PACS (Picture Archiving and Communication System) at variable combinations of the added filters. As a result, the Dose Area Product (DAP: $mGy{\cdot}cm^2$) and Entrance Surface Doses (ESDs: $mGy$) was lowest at 1 mmAl + 0.2 mmCu and highest at 0 mmAl. The histogram of the image quality by transmitted PACS was not significantly different at variable combinations of exposure parameters on the MATLAB. In conclusion, this study can be helpful for expecting radiation dose-exposure and control exposure parameters for the diagnostic X-ray radiography.

Shot Boundary Detection Using Global Information (전역적 정보를 이용한 샷 경계 검출)

  • Shin, Seong-Yoon;Shin, Kwang-Sung;Lee, Hyun-Chang;Jin, Chan-Yong;Rhee, Yang-Won
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2012.05a
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    • pp.149-150
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    • 2012
  • This paper presents a shot boundary detection method based on the global decision tree that allows for extraction of boundaries of high variations occurring due to camera breaks from frame difference values. For a start, difference values between frames are calculated through local X2-histogram and normalization. Next, the distances between difference values are calculated through normalization.

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