• Title/Summary/Keyword: Boundary Smoothing

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Reconstruction of the Lost Hair Depth for 3D Human Actor Modeling (3차원 배우 모델링을 위한 깊이 영상의 손실된 머리카락 영역 복원)

  • Cho, Ji-Ho;Chang, In-Yeop;Lee, Kwan-H.
    • Journal of the HCI Society of Korea
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    • v.2 no.2
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    • pp.1-9
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    • 2007
  • In this paper, we propose a reconstruction technique of the lost hair region for 3D human actor modeling. An active depth sensor system can simultaneously capture both color and geometry information of any objects in real-time. However, it cannot acquire some regions whose surfaces are shiny and dark. Therefore, to get a natural 3D human model, the lost region in depth image should be recovered, especially human hair region. The recovery is performed using both color and depth images. We find out the hair region using color image first. After the boundary of hair region is estimated, the inside of hair region is estimated using an interpolation technique and closing operation. A 3D mesh model is generated after performing a series of operations including adaptive sampling, triangulation, mesh smoothing, and texture mapping. The proposed method can generate recovered 3D mesh stream automatically. The final 3D human model allows the user view interaction or haptic interaction in realistic broadcasting system.

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Topology Correction for Flattening of Brain Cortex

  • Kwon Min Jeong;Park Hyun Wook
    • Journal of Biomedical Engineering Research
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    • v.26 no.2
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    • pp.73-86
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    • 2005
  • We need to flatten the brain cortex to smooth surface, sphere, or 2D plane in order to view the buried sulci. The rendered 3D surface of the segmented white matter and gray matter does not have the topology of a sphere due to the partial volume effect and segmentation error. A surface without correct topology may lead to incorrect interpretation of local structural relationships and prevent cortical unfolding. Although some algorithms try to correct topology, they require heavy computation and fail to follow the deep and narrow sulci. This paper proposes a method that corrects topology of the rendered surface fast, accurately, and automatically. The proposed method removes fractions beside the main surface, fills cavities in the inside of the main surface, and removes handles in the surface. The proposed method to remove handles has three-step approach. Step 1 performs smoothing operation on the rendered surface. In Step 2, vertices of sphere are gradually deformed to the smoothed surfaces and finally to the boundary of the segmented white matter and gray matter. The Step 2 uses multi-resolutional approach to prevent the deep sulci from geometrical intersection. In Step 3, 3D binary image is constructed from the deformed sphere of Step 2 and 3D surface is regenerated from the 3D binary image to remove intersection that may happen. The experimental results show that the topology is corrected while principle sulci and gyri are preserved and the computation amount is acceptable.

The Improved Deblocking Filter for Low-bit Rate H.264/AVC Video (저해상도 H.264/AVC 비디오를 위한 개선된 디블럭킹 필터)

  • Kwon, Dong-Jin;Ryu, Sung-Pil;Kwak, Nae-Joung;Ahn, Jae-Hyeong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.18 no.2
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    • pp.284-289
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    • 2008
  • H.264/AVC among moving picture compression standard is the standard format for high compression rate and reliable video transimission. It generates blocking effects in video due to compressing video using block-based DCT and includes de-blocking filter to reduce blocking effect. Therefore, the filter makes the video over-smoothing and the quality of it is reduced. In this paper, we propose a improved de-blocking filter to solve the demerit. The proposed de-blocking filter redetermine the block boundary strength and apply the comer filtering to eliminate artifacts in low frequency domain. To evaluate the performance, we apply the proposed deblocking filter and exiting method to various video and evaluated the quality of image subjectively and objectively by analyzing the result. The simulation result shows the proposed method preserves the edge of video, reduces blocking effects and improves PSNR than the existing method.

Image processing in a discrete polar coordinate system based on L1-norm (L1-norm 기반 이산 극좌표에서의 영상처리)

  • John, Min-Su;Lee, Nam-Koo;Kim, Won-Ha;Kim, Sung-Min
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.45 no.4
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    • pp.20-28
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    • 2008
  • We propose a radial image processing method in a discrete polar coordinate system based on L1-norm. For this purpose, we first verified that the polar coordinate based on L2-norm can not exist in discrete system and then develop a method converting the Cartesian coordinate to the discrete polar coordinate. We apply the proposed method to smooth mass images of breast tissue and to detect the boundaries of extremely deformable objects. Compared to the Gaussian smoothing method performed in the Cartesian coordinate system, the proposed method stabilized the image signal while maintaining the overall radial shape of mass images. The proposed boundary detection method can detect shapes with high precision while conventional edge detectors can not accurately detect the shape of deformable objects. We also exploit the method to perform pupil detection and have had good experimental results.

Patterns and Trends of Water Level and Water Quality at the Namgang Junction in the Nakdong River Based on Hourly Measurement Time Series Data (낙동강 남강 합류부 수위와 수질 패턴 및 추세)

  • Yang, Deuk Seok;Im, Teo Hyo;Lee, In Jung;Jung, Kang Young;Kim, Gyeong Hoon;Kwon, Heon Gak;Yoo, Je-Chul;Ahn, Jung Min
    • Journal of Environmental Science International
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    • v.27 no.2
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    • pp.63-74
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    • 2018
  • As part of the Four Major Rivers Restoration Project, multifunctional weirs have been constructed in the rivers and operated for river-level management. As the weirs play a role in draining water from tributaries, the aim of this study was to determine the influence of the weirs on the water level of the Nam River, which is one of the Nakdong River's tributaries. Self-organizing maps (SOMs) and a locally weighted scatterplot smoothing (LOWESS) technique were applied to analyze the patterns and trends of water level and quality of the Nakdong River, considering the operation of the Changnyeong-Haman weir, which is located where the Nam River flows into the Nakdong River. The software program HEC-RAS was used to find the boundary points where the water is well drained. Per the study results at the monitoring points ranging between the junction of the two rivers and 17.5 km upstream toward the Nam River, the multifunctional weir influenced the water level at the Geoyrong and Daesan observation stations on the Nam River and the water quality based on automatic monitoring at the Chilseo station on the Nakdong River was affected strongly by the Nakdong River and partly by the Nam River.

Classifying Indian Medicinal Leaf Species Using LCFN-BRNN Model

  • Kiruba, Raji I;Thyagharajan, K.K;Vignesh, T;Kalaiarasi, G
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.10
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    • pp.3708-3728
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    • 2021
  • Indian herbal plants are used in agriculture and in the food, cosmetics, and pharmaceutical industries. Laboratory-based tests are routinely used to identify and classify similar herb species by analyzing their internal cell structures. In this paper, we have applied computer vision techniques to do the same. The original leaf image was preprocessed using the Chan-Vese active contour segmentation algorithm to efface the background from the image by setting the contraction bias as (v) -1 and smoothing factor (µ) as 0.5, and bringing the initial contour close to the image boundary. Thereafter the segmented grayscale image was fed to a leaky capacitance fired neuron model (LCFN), which differentiates between similar herbs by combining different groups of pixels in the leaf image. The LFCN's decay constant (f), decay constant (g) and threshold (h) parameters were empirically assigned as 0.7, 0.6 and h=18 to generate the 1D feature vector. The LCFN time sequence identified the internal leaf structure at different iterations. Our proposed framework was tested against newly collected herbal species of natural images, geometrically variant images in terms of size, orientation and position. The 1D sequence and shape features of aloe, betel, Indian borage, bittergourd, grape, insulin herb, guava, mango, nilavembu, nithiyakalyani, sweet basil and pomegranate were fed into the 5-fold Bayesian regularization neural network (BRNN), K-nearest neighbors (KNN), support vector machine (SVM), and ensemble classifier to obtain the highest classification accuracy of 91.19%.

Conditional Density based Statistical Prediction

  • J Rama Devi;K. Koteswara Rao;M Venkateswara Rao
    • International Journal of Computer Science & Network Security
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    • v.23 no.6
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    • pp.127-139
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    • 2023
  • Numerous genuine issues, for example, financial exchange expectation, climate determining and so forth has inalienable arbitrariness related with them. Receiving a probabilistic system for forecast can oblige this dubious connection among past and future. Commonly the interest is in the contingent likelihood thickness of the arbitrary variable included. One methodology for expectation is with time arrangement and auto relapse models. In this work, liner expectation technique and approach for computation of forecast coefficient are given and likelihood of blunder for various assessors is determined. The current methods all need in some regard assessing a boundary of some accepted arrangement. In this way, an elective methodology is proposed. The elective methodology is to gauge the restrictive thickness of the irregular variable included. The methodology proposed in this theory includes assessing the (discretized) restrictive thickness utilizing a Markovian definition when two arbitrary factors are genuinely needy, knowing the estimation of one of them allows us to improve gauge of the estimation of the other one. The restrictive thickness is assessed as the proportion of the two dimensional joint thickness to the one-dimensional thickness of irregular variable at whatever point the later is positive. Markov models are utilized in the issues of settling on an arrangement of choices and issue that have an innate transience that comprises of an interaction that unfurls on schedule on schedule. In the nonstop time Markov chain models the time stretches between two successive changes may likewise be a ceaseless irregular variable. The Markovian methodology is especially basic and quick for practically all classes of classes of issues requiring the assessment of contingent densities.

Automatic Boundary Detection of Carotid Intima-Media based on Multiresolution Snake (다해상도 스네이크를 통한 경동맥 내막-중막 경계선 자동추출)

  • Lee, Yu-Bu;Choi, Yoo-Joo;Kim, Myoung-Hee
    • The KIPS Transactions:PartA
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    • v.14A no.2
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    • pp.77-84
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    • 2007
  • The intima media thickness(IMT) of the carotid artery from B mode ultrasound images has recently been proposed as the most useful index of individual atherosclerosis and can be used to predict major cardiovascular events. Ultrasonic measurements of the IMT are conventionally obtained by manually tracing interfaces between tissue layers. The drawbacks of this method are the inter and intra observer variability and its inefficiency. In this paper, we present a multiresolution snake method combined with the dynamic programming, which overcomes the various noises and sensitivity to initialization of conventional snake. First, an image pyramid is constructed using the Gaussian pyramid that maintains global edge information with smoothing in the images, and then the boundaries are automatically detected in the lowest resolution level by minimizing a cost function based on dynamic programming. The cost function includes cost terms which are representing image features and geometrical continuity of the vessel interfaces. Since the detected boundaries are selected as initial contour of the snake for the next level, this automated approach solves the problem of the initialization. Moreover, the proposed snake improves the problem of converging th the local minima by defining the external energy based on multiple image features. In this paper, our method has been validated by computing the correlation between manual and automatic measurements. This automated detection method has obtained more accurate and reproducible results than conventional edge detection by considering multiple image features.

Revision of ART with Iterative Partitioning for Performance Improvement (입력 도메인 반복 분할 기법 성능 향상을 위한 고려 사항 분석)

  • Shin, Seung-Hun;Park, Seung-Kyu;Jung, Ki-Hyun
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.46 no.3
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    • pp.64-76
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    • 2009
  • Adaptive Random Testing through Iterative Partitioning(IP-ART) is one of Adaptive Random Testing(ART) techniques. IP-ART uses an iterative partitioning method for input domain to improve the performances of early-versions of ART that have significant drawbacks in computation time. Another version of IP-ART, named with EIP-ART(IP-ART with Enlarged Input Domain), uses virtually enlarged input domain to remove the unevenly distributed parts near the boundary of the domain. EIP-ART could mitigate non-uniform test case distribution of IP-ART and achieve relatively high performances in a variety of input domain environments. The EIP-ART algorithm, however, have the drawback of higher computation time to generate test cases mainly due to the additional workload from enlarged input domain. For this reason, a revised version of IP-ART without input domain enlargement needs to improve the distribution of test cases to remove the additional time cost. We explore three smoothing algorithms which influence the distribution of test cases, and analyze to check if any performance improvements take place by them. The simulation results show that the algorithm of a restriction area management achieves better performance than other ones.

A Study on Real-time Tracking Method of Horizontal Face Position for Optimal 3D T-DMB Content Service (지상파 DMB 단말에서의 3D 컨텐츠 최적 서비스를 위한 경계 정보 기반 실시간 얼굴 수평 위치 추적 방법에 관한 연구)

  • Kang, Seong-Goo;Lee, Sang-Seop;Yi, June-Ho;Kim, Jung-Kyu
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.48 no.6
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    • pp.88-95
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    • 2011
  • An embedded mobile device mostly has lower computation power than a general purpose computer because of its relatively lower system specifications. Consequently, conventional face tracking and face detection methods, requiring complex algorithms for higher recognition rates, are unsuitable in a mobile environment aiming for real time detection. On the other hand, by applying a real-time tracking and detecting algorithm, we would be able to provide a two-way interactive multimedia service between an user and a mobile device thus providing a far better quality of service in comparison to a one-way service. Therefore it is necessary to develop a real-time face and eye tracking technique optimized to a mobile environment. For this reason, in this paper, we proposes a method of tracking horizontal face position of a user on a T-DMB device for enhancing the quality of 3D DMB content. The proposed method uses the orientation of edges to estimate the left and right boundary of the face, and by the color edge information, the horizontal position and size of face is determined finally to decide the horizontal face. The sobel gradient vector is projected vertically and candidates of face boundaries are selected, and we proposed a smoothing method and a peak-detection method for the precise decision. Because general face detection algorithms use multi-scale feature vectors, the detection time is too long on a mobile environment. However the proposed algorithm which uses the single-scale detection method can detect the face more faster than conventional face detection methods.