• Title/Summary/Keyword: Accumulated Histogram

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Sea fog detection near Korea peninsula by using GMS-5 Satellite Data(A case study)

  • Chung, Hyo-Sang;Hwang, Byong-Jun;Kim, Young-Haw;Son, Eun-Ha
    • Proceedings of the KSRS Conference
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    • 1999.11a
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    • pp.214-218
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    • 1999
  • The aim of our study is to develop new algorism for sea fog detection by using Geostational Meteorological Satellite-5(GMS-5) and suggest the techniques of its continuous detection. So as to detect daytime sea fog/stratus(00UTC, May 10, 1999), visible accumulated histogram method and surface albedo method are used. The characteristic value during daytime showed A(min) > 20% and DA < 10% when visble accumulated histogram method was applied. And the sea fog region which detected is of similarity in composite image and surface albedo method. In case of nighttime sea fog(18UTC, May 10, 1999), infrared accumulated histogram method and maximum brightness temperature method are used, respectively. Maximum brightness temperature method(T_max method) detected sea fog better than IR accumulated histogram method. In case of T_max method, when infrared value is larger than T_max, fog is detected, where T_max is an unique value, maximum infrared value in each pixel during one month. Then T_max is beneath 700hpa temperature of GDAPS(Global Data Assimilation and Prediction System). Sea fog region which detected by T_max method was similar to the result of National Oceanic and Atmosheric Administration/Advanced Very High Resolution Radiometer (NOAA/AVHRR) DCD(Dual Channel Difference). But inland visibility and relative humidity didn't always agreed well.

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Study on sea fog detection near Korea peninsula by using GMS-5 Satellite Data (GMS-5 위성자료를 이용한 한반도 주변 해무탐지 연구)

  • 윤홍주
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.4 no.4
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    • pp.875-884
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    • 2000
  • Sea fog/stratus is very difficult to detect because of the characteristics of air-sea interaction and locality ,and the scantiness of the observed data from the oceans such as ships or ocean buoys. The aim of our study develops new algorism for sea fog detection by using Geostational Meteorological Satellite-5(GMS-5) and suggests the technics of its continuous detection. In this study, atmospheric synoptic patterns on sea fog day of May, 1999 are classified; cold air advection type(OOUTC, May 10, 1999) and warm air advection type(OOUTC, May 12, 1999), respectively, and we collected two case days in order to analyze variations of water vapor at Osan observation station during May 9-10, 1999.So as to detect daytime sea fog/stratus(OOUTC, May 10, 1999), composite image, visible accumulated histogram method and surface albedo method are used. The characteristic value during day showed A(min) .20% and DA < 10% when visible accumulated histogram method was applied. And the sea fog region which is detected is similar in composite image analysis and surface albedo method. Inland observation which visibility and relative humidity is beneath 1Km and 80%, respectively, at OOUTC, May 10,1999; Poryoung for visble accumulated histogram method and Poryoung, Mokp'o and Kangnung for surface albedo method. In case of nighttime sea fog(18UTC, May 10, 1999), IR accumulated histogram method and Maximum brightness temperature method are used, respectively. Maxium brightness temperature method dectected sea fog better than IR accumulated histogram method with the charateristic value that is T_max < T_max_trs, and then T_max is beneath 700hPa temperature of GDAPS(Global Data Assimilation and Prediction System). Sea fog region which is detected by Maxium brighness temperature method was similar to the result of National Oceanic and Atmosheric Administratio/Advanced Very High Resolution Radiometer (NOAA/AVHRR) DCD(Dual Channel Difference), but usually visibility and relative humidity are not agreed well in inland.

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Rotation Invariant Histogram of Oriented Gradients

  • Cheon, Min-Kyu;Lee, Won-Ju;Hyun, Chang-Ho;Park, Mignon
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.11 no.4
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    • pp.293-298
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    • 2011
  • In this paper, we propose a new image descriptor, that is, a rotation invariant histogram of oriented gradients (RIHOG). RIHOG overcomes a disadvantage of the histogram of oriented gradients (HOG), which is very sensitive to image rotation. The HOG only uses magnitude values of a pixel without considering neighboring pixels. The RIHOG uses the accumulated relative magnitude values of corresponding relative orientation calculated with neighboring pixels, which has an effect on reducing the sensitivity to image rotation. The performance of RIHOG is verified via the index of classification and classification of Brodatz texture data.

Fast Human Detection Method in Range Data using Adaptive UV-histogram and Template Matching (적응적 UV-histogram과 템플릿 매칭을 이용한 거리 영상에서의 고속 인간 검출 방법)

  • Yoon, Bumsik;Kim, Whoi-Yul
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.9
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    • pp.119-128
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    • 2014
  • In this paper, a fast human detection method using adaptive UV-histogram and template matching is proposed. The proposed method improves the detection rate in the scene of complex environment. The method firstly generates U-histogram to extract human candidates and adaptively generates V-histogram for each labled U-histogram, thus it could extract humans correctly, which was impossible in the previous method. The method tries to match the human candidates with the adaptively sized omega shape template to the focal length and distance in order to improve the detection accuracy. It also detects false positives by rematching the template with accumulated foreground images and hence is robust to the occlusion. Experimental results showed that the proposed method has superior performance to the Bae's method in the complex environment with about 15% improvement in precision and 80% in recall and has 20 times faster processing time than Xia's method.

Using the obstacle position information of the mobile robot in the two-dimensional cartography Study (장애물 위치 정보를 이용한 모바일 로봇의 2차원 지도 작성에 관한 연구)

  • Lee, Jun-Ho;Hong, Hyun-Ju;Kang, Seog-Joo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.13 no.1
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    • pp.30-38
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    • 2014
  • The purpose of this study is to build and manage environment models with line segments from sonar range data on obstacles in unknown and varied environments. The proposed method therefore employs a two-stage data-transform process in order to extract environmental line segments from range data on obstacles. In the first stage, the occupancy grid extracted from the range data is accumulated to form a two-dimensional local histogram grid. In the second stage, a line histogram extracted from a local histogram grid is based on a Hough transform, and matching serves as a means of comparing each of the segments on a global line segments map against the line segments to detect the degree of similarity in the overlap, orientation, and arrangement. Each of these tests is formulated by comparing one of the parameters in the segment representation. After the tests, new line segments can be found at maximum-density cells in the line histogram, and they are composed onto the global line segment map. The proposed technique is demonstrated in experiments in an indoor environment.

Skin Region Detection Using a Mean Shift Algorithm Based on the Histogram Approximation

  • Byun, Ki-Won;Nam, Ki-Gon;Ye, Soo-Young
    • Transactions on Electrical and Electronic Materials
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    • v.13 no.1
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    • pp.10-15
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    • 2012
  • In conventional, skin detection methods using for skin color definitions is based on prior knowledge. By experimentation, the threshold value for dividing the background from the skin region is determined subjectively. A drawback of such techniques is that their performance is dependent on a threshold value which is estimated from repeated experiments. To overcome this, the present paper introduces a skin region detection method. This method uses a histogram approximation based on the mean shift algorithm. This proposed method applies the mean shift procedure to a histogram of a skin map of the input image. It is generated by comparing with the standard skin colors in the $C_bC_r$ color space. It divides the background from the skin region by selecting the maximum value according to the brightness level. As the histogram has the form of a discontinuous function. It is accumulated according to the brightness values of the pixels. It is then, approximated by a Gaussian mixture model (GMM) using the Bezier curve technique. Thus, the proposed method detects the skin region using the mean shift procedure to determine a maximum value. Rather than using a manually selected threshold value, as in existing techniques this becomes the dividing point. Experiments confirm that the new procedure effectively detects the skin region.

(Content-Based Video Copy Detection using Motion Directional Histogram) (모션의 방향성 히스토그램을 이용한 내용 기반 비디오 복사 검출)

  • 현기호;이재철
    • Journal of KIISE:Software and Applications
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    • v.30 no.5_6
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    • pp.497-502
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    • 2003
  • Content-based video copy detection is a complementary approach to watermarking. As opposed to watermarking, which relies on inserting a distinct pattern into the video stream, video copy detection techniques match content-based signatures to detect copies of video. Existing typical content-based copy detection schemes have relied on image matching which is based on key frame detection. This paper proposes a motion directional histogram, which is quantized and accumulated the direction of motion, for video copy detection. The video clip is represented by a motion directional histogram as a 1-dimensional graph. This method is suitable for real time indexing and counting the TV CF verification that is high motion video clips.

Video Quality Metric Using One-Dimensional Histograms of Motion Vectors (움직임 벡터의 1차원 히스토그램을 이용한 비디오 화질 평가 척도)

  • Han, Ho-Sung;Kim, Dong-O;Park, Bae-Hong;Sim, Dong-Gyu
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.2
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    • pp.21-28
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    • 2008
  • This paper proposes a novel reduced-reference assessment method for video quality assessment, in which one-dimensional (1-D) histograms of motion vectors (MVs) are used as features of videos. The proposed method is more efficient than the conventional methods in view of computation time, because the proposed quality metric decodes MVs directly from video stream in the parsing process instead of reconstructing the distorted video at the receiver. Moreover, in view of data size, the propose method is efficient because a sender transmits 1-D histograms of MVs accumulated over whole input video sequences. Here, we use 1-D histograms of MVs accumulated over the whole video sequences, which is different from the conventional methods that assessed each image independently. For testing the similarity between histograms, we use histogram intersection and histogram difference methods. We compare the proposed method with the conventional methods for 52 video clips, which are coded under varying bit rate, image size, and frame rate. Experimental results show that the proposed method is more efficient than the conventional methods and that the proposed method is more similar to the mean opinion score (MOS) than conventional algorithms.

A Study on Estimation of Fatigue Life of Aged Continuous Welded Rail using the Field Test (현장측정을 통한 노후 레일의 피로수명 평가에 관한 연구)

  • Kong, Sun-Yong;Sung, Deok-Yong;Kim, Jun-Hyung;Park, Yong-Gul
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.352-364
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    • 2007
  • It is essential to reduce track maintenance costs and to extend the periodic replacements of continuous welded rails based on accumulated passing tonnage. As recently train load decrease and rail joints wear down less, the periodic replacements of continuous welded rails can be extended. There are many kinds of rail damage like squat, head-check and corrugation. These can be taken nondestructive or naked eye test. So the periodic replacements of continuous welded rails based on accumulated passing tonnage were examine with focusing on a crack of rail bottom of continuous welded rail. Therefore, this study measure dynamic response of track by metro train load, it compute impact coefficient and track spring coefficient for estimating a condition of actual track system. Also, it is converted the measured stress waveform into stress frequency histogram by the rain-flow counting methods, and then the equivalence of stress is calculated. As apply s-n curve of a new welded rail, accumulated fatigue damage ratio of laid rail and remaining service lives is estimated. This study suggest a plan of the periodic replacements of continuous welded rails based on accumulated passing tonnage classified by the types of track system.

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Stress Histogram Analysis of Steel Plate Girder Railway Bridge due to Service Load Histories (실동하중에 의한 강판형철도교의 응력빈도해석)

  • Hwang, In-Gu;Kim, Yeon-Tae
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.928-933
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    • 2004
  • Despite the number of steel bridges being under in service more than 50 years reaches about 50$\%$ in present, the quantitative estimation in maintenance on steel railway bridges is not possible because a ton of the field data in the bridges have not been plentifully accumulated. Therefore, a series of field tests on the steel plate girder bridge, the typical types of steel railway bridges, are executed, and the stress characteristics of main members in steel plate girder railway bridges are quantitatively estimated in this study.

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