• Title/Summary/Keyword: Change Detection

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Night-Time Blind Spot Vehicle Detection Using Visual Property of Head-Lamp (전조등의 시각적 특성을 이용한 야간 사각 지대 차량 검출 기법)

  • Joung, Jung-Eun;Kim, Hyun-Koo;Park, Ju-Hyun;Jung, Ho-Youl
    • IEMEK Journal of Embedded Systems and Applications
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    • v.6 no.5
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    • pp.311-317
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    • 2011
  • The blind spot is an area where drivers visibility does not reach. When drivers change a lane to adjacent lane, they need to give an attention because of the blind spot. If drivers try to change lane without notice of vehicle approaching in the blind spot, it causes a reason to have a car accident. This paper proposes a night-time blind spot vehicle detection using cameras. At nighttime, head-lights are used as characteristics to detect vehicles. Candidates of headlight are selected by high luminance feature and then shape filter and kalman filter are employed to remove other noisy blobs having similar luminance to head-lights. In addition, vehicle position is estimated from detected head-light, using virtual center line represented by approximated the first order linear equation. Experiments show that proposed method has relatively high detection porformance in clear weather independent to the road types, but has not sufficient performance in rainy weather because of various ground reflectors.

Multiple Structural Change-Point Estimation in Linear Regression Models

  • Kim, Jae-Hee
    • Communications for Statistical Applications and Methods
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    • v.19 no.3
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    • pp.423-432
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    • 2012
  • This paper is concerned with the detection of multiple change-points in linear regression models. The proposed procedure relies on the local estimation for global change-point estimation. We propose a multiple change-point estimator based on the local least squares estimators for the regression coefficients and the split measure when the number of change-points is unknown. Its statistical properties are shown and its performance is assessed by simulations and real data applications.

Identifying Urban Heat Island Effects due to Urban Land Use Change

  • Shin Dong-hoon;Lee Kyoo-seock
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.22-24
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    • 2004
  • The land use has changed rapidly since 1960s in accordance with urbanization in Seoul Metropolitan Region. As a result, the urban microclimate has undergone changes as well. This study aims to recognize trend of the urban heat island change which is caused by land use change during urbanization in large city. Thermal data of Landsat TM images in 1987 and 1999 were for land surface temperature change detection in the study.

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An On-Line Real-Time SPC Scheme and Its Performance

  • Nishina, Ken
    • International Journal of Quality Innovation
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    • v.2 no.1
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    • pp.30-49
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    • 2001
  • This paper considers a recent environment in the manufacturing process in which data in large amounts can be obtained on-line in real-time. Under this environment an on-line real-time Statistical Process Control (SPC) scheme equipped with detection of a process change, change-point estimation, and recognition of the change pattern is proposed. The proposed SPC scheme is composed of a Cusum chart, filtering methods and Akaike Information Criterion (AIC). We examine the performance of this scheme by Monte Carlo simulation and show its usefulness.

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A Comparative Study of Wetland Change Detection Techniques Using Post-Classification Comparison and Image Differencing on Landsat-5 TM Data (랜�V-5호(號) TM 데이타를 이용(利用)한 구분후(區分后) 비교(比較) 및 영상대차(映像對差)의 습지대(濕地帶) 변화(變化) 탐지(探知) 기법(技法)에 관(關)한 비교연구(比較硏究))

  • Choung, Song Hak;Ulliman, Joseph J.
    • Journal of Korean Society of Forest Science
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    • v.81 no.4
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    • pp.346-356
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    • 1992
  • The extensive Snake River floodplain in Northwest United States has experienced major changes in water channels and vegetation types due to floodings. To detect the change of wetland cover-types for the period of 1985 and 1988, post-classification comparison and image differencing change detection techniques were evaluated using Landsat-5 TM digital data. Differenced infrared-band images indicated better accuracy indices than any visible-band images. A thresholding technique was applied to identify the change and no change categories from the transformed images produced by image differencing. The problems in using different accuracy indices, including the Kappa coefficient of agreement, overall accuracy, producer's accuracy, user's accuracy, and average accuracy(based on both the producer's and user's accuracy approaches) in determining an optimal threshold level, were examined.

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CHANGE DETECTION ANALYSIS OF FORESTED AREA IN THE TRANSITION ZONE AT HUSTAI NATIONAL PARK, CENTRAL MONGOLIA

  • Bayarsaikhan, Uudus;Boldgiv, Bazartseren;Kim, Kyung-Ryul;Park, Kyeng-Ae
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.426-429
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    • 2007
  • One of the widely used applications of remote sensing studies is environmental change detection and biodiversity conservation. The study area Hustai Mountain is situated in the transition zone between the Siberian taiga forest and Central Mongolian arid steppe. Hustai National Park carries out one of several reintroduction programs of takhi (wild horse or Equus ferus przewalskii) from various zoos in the world and it represents one of a few textbook examples of successful reintroduction of an animal extinct in the wild. In this paper we describe the results of an analysis on the change of remaining forest area over the 7-year period since Hustai Mountain was designated as a protected area for reintroduction to wild horses. Today the forested area covers approximately 5% of the Hustai National Park, mostly the north-facing slopes above 1400 m altitude. Birch (Betula platyphylla) and aspen (Populus tremula) trees are predominant in the forest. We used Landsat ETM+ images from two different years and multi temporal MODIS NDVI data. Land types were determined by supervised classification methods (Maximum Likelihood algorithm) verified with ground-truthing data and the Land Change Modeler (LCM) which was developed by Clark Labs. Forested area was classified into three different land types, namely the forest land, mountain meadow and mountain steppe. The study results illustrate that the remaining birch forest has rapidly changed to fragmented forest land and to open areas. Underlying causes for such a rapid change during the 15-year period may be manifold. However, the responsible factors appear to be the drying off and outbreak of forest pest species (such as gypsy moth or Lymantria dispar) in the area.

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An Efficient Scene Change Detection Algorithm Considering Brightness Variation (밝기 변화를 고려한 효율적인 장면전환 검출 알고리즘)

  • Kim Sang-Hyun
    • Journal of the Institute of Convergence Signal Processing
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    • v.6 no.2
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    • pp.74-81
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    • 2005
  • As the multimedia data increases, various scene change detection algorithms for video indexing and sequence matching have been proposed to efficiently manage and utilize digital media. In this paper, we propose a robust scene change detection algorithm for video sequences with abrupt luminance variations. To improve the accuracy and to reduce the computational complexity of video indexing with abrupt luminance variations, the proposed algorithm utilizes edge features as well as color features, which yields a remarkably better performance than conventional algorithms. In the proposed algorithm first we extract the candidate shot boundaries using color histograms and then determine using edge matching and luminance compensation if they are shot boundaries or luminance changes. If the scene contains trivial brightness variations, the edge matching and luminance compensation are performed only for shot boundaries. In experimental results, the proposed method gives remarkably a high performance and efficiency than the conventional methods with the similar computational complexity.

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Robust Illumination Change Detection Using Image Intensity and Texture (영상의 밝기와 텍스처를 이용한 조명 변화에 강인한 변화 검출)

  • Yeon, Seungho;Kim, Jaemin
    • Journal of Korea Multimedia Society
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    • v.16 no.2
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    • pp.169-179
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    • 2013
  • Change detection algorithms take two image frames and return the locations of newly introduced objects which cause differences between the images. This paper presents a new change detection method, which classifies intensity changes due to introduced objects, reflected light and shadow from the objects to their neighborhood, and the noise, and exactly localizes the introduced objects. For classification and localization, first we analyze the histogram of the intensity difference between two images, and estimate multiple threshold values. Second we estimate candidate object boundaries using the gradient difference between two images. Using those threshold values and candidate object boundaries, we segment the frame difference image into multiple regions. Finally we classify whether each region belongs to the introduced objects or not using textures in the region. Experiments show that the proposed method exactly localizes the objects in various scenes with different lighting.

Deforestation Analysis Using Unsupervised Change Detection Based on ITPCA (ITPCA 기반의 무감독 변화탐지 기법을 이용한 산림황폐화 분석)

  • Choi, Jaewan;Park, Honglyun;Park, Nyunghee;Han, Soohee;Song, Jungheon
    • Korean Journal of Remote Sensing
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    • v.33 no.6_3
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    • pp.1233-1242
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    • 2017
  • In this study, we tried to analyze deforestation due to forest fire by using KOMPSAT satellite imagery. For deforestation analysis, unsupervised change detection algorithm is applied to multitemporal images. Through ITPCA (ITerative Principal Component Analysis) of NDVI (Normalized Difference Vegetation Index) generated from multitemporal satellite images before and after forest fire, changed areas due to deforestation are extracted. In addition, a post-processing method using SRTM (Shuttle Radar Topographic Mission) data is involved in order to minimize the error of change detection. As a result of the experiment using KOMPSAT-2 and 3 images, it was confirmed that changed areas due to deforestation can be efficiently extracted.

A Fast Bayesian Detection of Change Points Long-Memory Processes (장기억 과정에서 빠른 베이지안 변화점검출)

  • Kim, Joo-Won;Cho, Sin-Sup;Yeo, In-Kwon
    • The Korean Journal of Applied Statistics
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    • v.22 no.4
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    • pp.735-744
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    • 2009
  • In this paper, we introduce a fast approach for Bayesian detection of change points in long-memory processes. Since a heavy computation is needed to evaluate the likelihood function of long-memory processes, a method for simplifying the computational process is required to efficiently implement a Bayesian inference. Instead of estimating the parameter, we consider selecting a element from the set of possible parameters obtained by categorizing the parameter space. This approach simplifies the detection algorithm and reduces the computational time to detect change points. Since the parameter space is (0, 0.5), there is no big difference between the result of parameter estimation and selection under a proper fractionation of the parameter space. The analysis of Nile river data showed the validation of the proposed method.