• Title/Summary/Keyword: Spatio-temporal edge

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Saptio-temporal Deinterlacing Based on Edge Direction and Spatio-temporal Brightness Variations (에지 방향성과 시공간 밝기 변화율을 고려한 시공간 De-Interlacing)

  • Jung, Jee-Hoon;Hong, Sung-Hoon
    • Journal of Broadcast Engineering
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    • v.16 no.5
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    • pp.873-882
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    • 2011
  • In this paper, we propose an efficient deinterlacing algorithm which interpolates the missing scan lines by weighted summing of the intra and the inter interpolation pixels according to the spatio-temporal variation. In the spatial interpolation, we adopt a new edge based spatial interpolation method which includes edge directional refinement. The conventional edge dependent interpolation algorithms are very sensitive to noise due to the failure of estimating edge direction. In order to exactly detect edge direction, our method first finds the edge directions around the pixel to be interpolated and then refines edge direction of the pixel using weighted maximun frequent filter. Futhermore, we improve the accuracy of motion detection by reducing the possibility of motion detection error using 3 tab median filter. In the final interpolation step, we adopt weighted sum of intra and inter interpolation pixels according to spatio-temporal variation ratio, thereby improving the quality in slow moving area. Simulation results show the efficacy of the proposed method with significant improvement over the previous methods in terms of the objective PSNR quality as well as the subjective image quality.

Moving Object Contour Detection Using Spatio-Temporal Edge with a Fixed Camera (고정 카메라에서의 시공간적 경계 정보를 이용한 이동 객체 윤곽선 검출 방법)

  • Kwak, Jae-Ho;Kim, Whoi-Yul
    • Journal of Broadcast Engineering
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    • v.15 no.4
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    • pp.474-486
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    • 2010
  • In this paper, we propose a new method for detection moving object contour using spatial and temporal edge. In general, contour pixels of the moving object are likely present around pixels with high gradient value along the time axis and the spatial axis. Therefore, we can detect the contour of the moving objects by finding pixels which have high gradient value in the time axis and spatial axis. In this paper, we introduce a new computation method, termed as temporal edge, to compute an gradient value along the time axis for any pixel on an image. The temporal edge can be computed using two input gray images at time t and t-2 using the Sobel operator. Temporal edge is utilized to detect a candidate region of the moving object contour and then the detected candidate region is used to extract spatial edge information. The final contour of the moving object is detected using the combination of these two edge information, which are temporal edge and spatial edge, and then the post processing such as a morphological operation and a background edge removing procedure are applied to remove noise regions. The complexity of the proposed method is very low because it dose not use any background scene and high complex operation, therefore it can be applied to real-time applications. Experimental results show that the proposed method outperforms the conventional contour extraction methods in term of processing effort and a ghost effect which is occurred in the case of entropy method.

Extended Adaptive Spatio-Temporal Auto-Regressive Model for Video Sequence (동영상에서의 확장된 시공간 적응적 Auto-regressive 모델의 연구)

  • Doo, Seok-Joo;Kang, Moon-Gi
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.11
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    • pp.54-59
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    • 1999
  • In this paper, a generalized auto-regressive(AR) model is proposed for linear prediction based on adaptive spatio-temporal support region(ASTSR). The conventional AR model suffers from the drawback that the prediction error increases in the edge region because the rectangular support region of the edge does not satisfy the stationary assumption. Thus, the proposed approach puts an emphasis on the formulation of a spatio-temporally adaptive support region for the AR model, called ASTSR. The ASTSR consists of two parts: the adaptive spatial support region(ASSR) connected with edges and the adaptive temporal support region(ATSR) related to temporal discontinuities. The AR model based on ASTSR not only produces more accurate model parameters but also reduces the computational complexity in the motion picture restoration.

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Ergosterol and Water Changes in Tricholoma matsutake Soil Colony during the Mushroom Fruiting Season

  • Koo, Chang-Duck;Lee, Dong-Hee;Park, Young-Woo;Lee, Young-Nam;Ka, Kang-Hyun;Park, Hyun;Bak, Won-Chull
    • Mycobiology
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    • v.37 no.1
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    • pp.10-16
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    • 2009
  • The purpose of this study is to understand spatio-temporal changes of active fungal biomass and water in Tricholoma matsutake soil colonies during the mushroom fruiting season. The active fungal biomass was estimated by analyzing ergosterol content at four different points within four replicated locations in a single circular T. matsutake colony at Ssanggok valley in the Sogri Mt. National Park in Korea during 2003 to 2005. The four points were the ahead of the colony, the front edge of the colony and 20 cm and 40 cm back from the front edge of the colony. Ergosterol content was 0.0 to 0.7 ${\mu}g$ per gram dried soil at the ahead, 2.5 to 4.8 ${\mu}g$ at the front edge, 0.5 to 1.8 ${\mu}g$ at the 20 cm back and 0.3 to 0.8 ${\mu}g$ at the 40 cm back. The ergosterol content was very high at the front edge where the T. matsutake hyphae were most active. However, ergosterol content did not significantly change during the fruiting season, September to October. Soil water contents were lower at the front edge and 20 cm back from the front edge of the colony than at the ahead and 40 cm back during the fruiting season. Soil water content ranged from 12 to 19% at the ahead, 10 to 11% at the edge, 9 to 11% at the 20 cm back and 11 to 15% at the 40 cm back. Our results suggest that the active front edge of the T. matsutake soil colony could be managed in terms of water relation and T. matsutake ectomycorrhizal root development.

Analyzing Difference of Urban Forest Edge Vegetation Condition by Land Cover Types Using Spatio-temporal Data Fusion Method (시공간 위성영상 융합기법을 활용한 도시 산림 임연부 인접 토지피복 유형별 식생 활력도 차이 분석)

  • Sung, Woong Gi;Lee, Dong Kun;Jin, Yihua
    • Journal of Environmental Impact Assessment
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    • v.27 no.3
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    • pp.279-290
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    • 2018
  • The importance of monitoring and assessing the status of urban forests in the aspect of urban forest management is emerging as urban forest edges increase due to urbanization and human impacts. The purpose of this study was to investigate the status of vegetation condition of urban forest edge that is affected by different land cover types using $NDVI_{max}$ images derived from FSDAF (Flexible Spatio-temporal DAta Fusion). Among 4 land cover types,roads had the greatest effect on the forest edge, especially up to 30m, and it was found to affect up to 90m in Seoul urban forest. It was also found that $NDVI_{max}$ increased with distance away from the forest edge. The results of this study are expected to be useful for assessing the effects of land cover types and land cover change on forest edges in terms of urban forest monitoring and urban forest management.

Object-Based Video Segmentation Using Spatio-temporal Entropic Thresholding and Camera Panning Compensation (시공간 엔트로피 임계법과 카메라 패닝 보상을 이용한 객체 기반 동영상 분할)

  • 백경환;곽노윤
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.4 no.3
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    • pp.126-133
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    • 2003
  • This paper is related to a morphological segmentation method for extracting the moving object in video sequence using global motion compensation and two-dimensional spatio-temporal entropic thresholding. First, global motion compensation is performed with camera panning vector estimated in the hierarchical pyramid structure constructed by wavelet transform. Secondly, the regions with high possibility to include the moving object between two consecutive frames are extracted block by block from the global motion compensated image using two-dimensional spatio-temporal entropic thresholding. Afterwards, the LUT classifying each block into one among changed block, uncertain block, stationary block according to the results classified by two-dimensional spatio-temporal entropic thresholding is made out. Next, by adaptively selecting the initial search layer and the search range referring to the LUT, the proposed HBMA can effectively carry out fast motion estimation and extract object-included region in the hierarchical pyramid structure. Finally, after we define the thresholded gradient image in the object-included region, and apply the morphological segmentation method to the object-included region pixel by pixel and extract the moving object included in video sequence. As shown in the results of computer simulation, the proposed method provides relatively good segmentation results for moving object and specially comes up with reasonable segmentation results in the edge areas with lower contrast.

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Time-Space Variability Analysis for the Weekly Passenger Flow of the Seoul Subway System: Based on Dynamic Visualization Methods (서울 대도시권 지하철 통행흐름의 요일 간 변이성 분석: 동적 시각화방법을 토대로)

  • Lee, Keumsook;Kim, Ho Sung;Park, Jong Soo
    • Journal of the Economic Geographical Society of Korea
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    • v.20 no.2
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    • pp.158-172
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    • 2017
  • This study analyzes the time-space variability for the weekly passenger flow of the Seoul Subway system based on the dynamic visualization methods. For the purpose, we utilize one-week T-card transaction databases. By applying data mining algorithms, we extract passenger data for edge flows, on/off passengers at each subway station per minute interval time. It is practically intractable to analyze such spatio-temporal passenger flows by general statistical techniques. We employ dynamic visualization methods to analyze intuitively and to grasp effectively characteristics of the diurnal passenger flows on the Seoul Metropolitan Subway system during one week. As the result, we found that substantial differences exist on the spatio-temporal distribution patterns among days as well as between weekdays and weekend. We also investigates the time-space variability among eight major centers, and we found wide differences in their spatio-temporal distribution patterns.

Content-Based Video Retrieval Algorithms using Spatio-Temporal Information about Moving Objects (객체의 시공간적 움직임 정보를 이용한 내용 기반 비디오 검색 알고리즘)

  • Jeong, Jong-Myeon;Moon, Young-Shik
    • Journal of KIISE:Software and Applications
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    • v.29 no.9
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    • pp.631-644
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    • 2002
  • In this paper efficient algorithms for content-based video retrieval using motion information are proposed, including temporal scale-invariant retrieval and temporal scale-absolute retrieval. In temporal scale-invariant video retrieval, the distance transformation is performed on each trail image in database. Then, from a given que교 trail the pixel values along the query trail are added in each distance image to compute the average distance between the trails of query image and database image, since the intensity of each pixel in distance image represents the distance from that pixel to the nearest edge pixel. For temporal scale-absolute retrieval, a new coding scheme referred to as Motion Retrieval Code is proposed. This code is designed to represent object motions in the human visual sense so that the retrieval performance can be improved. The proposed coding scheme can also achieve a fast matching, since the similarity between two motion vectors can be computed by simple bit operations. The efficiencies of the proposed methods are shown by experimental results.

Multi-View Wyner-Ziv Video Coding Based on Spatio-temporal Adaptive Estimation (시공간 적응적인 예측에 기초한 다시점 위너-지브 비디오 부호화 기법)

  • Lee, Beom-yong;Kim, Jin-soo
    • The Journal of the Korea Contents Association
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    • v.16 no.6
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    • pp.9-18
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    • 2016
  • This paper proposes a multi-view Wyner-Ziv Video coding scheme based on spatio-temporal adaptive estimation. The proposed algorithm is designed to search for a better estimated block with joint bi-directional motion estimation by introducing weights between temporal and spatial directions, and by classifying effectively the region of interest blocks, which is based on the edge detection and the synthesis, and by selecting the reference estimation block from the effective motion vector analysis. The proposed algorithm exploits the information of a single frame viewpoint and adjacent frame viewpoints, simultaneously and then generates adaptively side information in a variety of closure, and reflection regions to have a better performance. Through several simulations with multi-view video sequences, it is shown that the proposed algorithm performs visual quality improvement as well as bit-rate reduction, compared to the conventional methods.

Spatio-Temporal Video De-interlacing Algorithm Based on MAP Estimation (MAP 예측기 기반의 시공간 동영상 순차주사화 알고리즘)

  • Lee, Ho-Taek;Song, Byung-Cheol
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.49 no.2
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    • pp.69-75
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    • 2012
  • This paper presents a novel de-interlacing algorithm that can make up motion compensation errors by using maximum a posteriori (MAP) estimator. First, a proper registration is performed between a current field and its adjacent fields, and the progressive frame corresponding to the current field is found via MAP estimator based on the computed registration information. Here, in order to obtain a stable solution, well-known bilateral total variation (BTV)-based regularization is employed. Next, so-called feathering artifacts are detected on a block basis effectively. So, edge-directional interpolation is applied to the pixels where feathering artifact may happen, instead of the above-mentioned temporal de-interlacing. Experimental results show that the PSNR of the proposed algorithm is on average 4dB higher than that of previous studies and provides the better subjective quality than the previous works.