• Title/Summary/Keyword: distance transform

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A Fast Encoding Algorithm for Image Vector Quantization Based on Prior Test of Multiple Features (복수 특징의 사전 검사에 의한 영상 벡터양자화의 고속 부호화 기법)

  • Ryu Chul-hyung;Ra Sung-woong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.12C
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    • pp.1231-1238
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    • 2005
  • This paper presents a new fast encoding algorithm for image vector quantization that incorporates the partial distances of multiple features with a multidimensional look-up table (LUT). Although the methods which were proposed earlier use the multiple features, they handles the multiple features step by step in terms of searching order and calculating process. On the other hand, the proposed algorithm utilizes these features simultaneously with the LUT. This paper completely describes how to build the LUT with considering the boundary effect for feasible memory cost and how to terminate the current search by utilizing partial distances of the LUT Simulation results confirm the effectiveness of the proposed algorithm. When the codebook size is 256, the computational complexity of the proposed algorithm can be reduced by up to the $70\%$ of the operations required by the recently proposed alternatives such as the ordered Hadamard transform partial distance search (OHTPDS), the modified $L_2-norm$ pyramid ($M-L_2NP$), etc. With feasible preprocessing time and memory cost, the proposed algorithm reduces the computational complexity to below the $2.2\%$ of those required for the exhaustive full search (EFS) algorithm while preserving the same encoding quality as that of the EFS algorithm.

Implementation of Mouse Function Using Web Camera and Hand (웹 카메라와 손을 이용한 마우스 기능의 구현)

  • Kim, Seong-Hoon;Woo, Young-Woon;Lee, Kwang-Eui
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.5
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    • pp.33-38
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    • 2010
  • In this paper, we proposed an algorithm implementing mouse functions using hand motion and number of fingers which are extracted from an image sequence. The sequence is acquired through a web camera and processed with image processing algorithms. The sequence is first converted from RGB model to YCbCr model to efficiently extract skin area and the extracted area is further processed using labeling, opening, and closing operations to decide the center of a hand. Based on the center position, the number of fingers is decided, which serves as the information to decide and perform a mouse function. Experimental results show that 94.0% of pointer moves and 96.0% of finger extractions are successful, which opens the possibility of further development for a commercial product.

Quantification of 3D Pore Structure in Glass Bead Using Micro X-ray CT (Micro X-ray CT를 이용한 글라스 비드의 3차원 간극 구조 정량화)

  • Jung, Yeon-Jong;Yun, Tae-Sup
    • Journal of the Korean Geotechnical Society
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    • v.27 no.11
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    • pp.83-92
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    • 2011
  • The random and heterogeneous pore structure is a significant factor that dominates physical and mechanical behaviors of soils such as fluid flow and geomechanical responses driven by loading. The characterization method using non-destructive testing such as micro X-ray CT technique which has a high resolution with micrometer unit allows to observe internal structure of soils. However, the application has been limited to qualitatively observe 2D and 3D CT images and to obtain the void ratio at macro-scale although the CT images contain enormous information of materials of interests. In this study, we constructed the 3D particle and pore structures based on sequentially taken 2D images of glass beads and quantitatively defined complex pore structure with void cell and void channel. This approach was enabled by implementing image processing techniques that include coordinate transformation, binarization, Delaunay Triangulation, and Euclidean Distance Transform. It was confirmed that the suggested algorithm allows to quantitatively evaluate the distribution of void cells and their connectivity of heterogeneous pore structures for glass beads.

Coordinates Transformation and Correction Techniques of the Distorted Omni-directional Image (왜곡된 전 방향 영상에서의 좌표 변환 및 보정)

  • Cha, Sun-Hee;Park, Young-Min;Cha, Eui-Young
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.1
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    • pp.816-819
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    • 2005
  • This paper proposes a coordinate correction technique using the transformation of 3D parabolic coordinate function and BP(Back Propagation) neural network in order to solve space distortion problem caused by using catadioptric camera. Although Catadioptric camera can obtain omni-directional image at all directions of 360 degrees, it makes an image distorted because of an external form of lens itself. Accordingly, To obtain transformed ideal distance coordinate information from distorted image on 3 dimensional space, we use coordinate transformation function that uses coordinates of a focus at mirror in the shape of parabolic plane and another one which projected into the shape of parabolic from input image. An error of this course is modified by BP neural network algorithm.

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Key Frame Extraction and Region Segmentation-based Video Retrieval in Compressed Domain (압축영역에서의 대표프레임 추출 및 영역분할기반 비디오 검색 기법)

  • 강응관;김성주;송호근;최종수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.9B
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    • pp.1713-1720
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    • 1999
  • This paper presents a new key frame extraction technique, for scene change detection, using the proposed AHIM (Accumulative Histogram Intersection Measure) from the DC image constructed by DCT DC coefficients in the compressed video sequence that is video compression standard such as MPEG. For fast content-based browsing and video retrieval in a video database, we also provide a novel coarse-to-fine video indexing scheme. In the extracted key frame, we perform the region segmentation as a preprocessing. First, the segmented image is projected with the horizontal direction, then we transform the result into a histogram, which is saved as a database index. In the second step, we calculate the moments and change them into a distance value. From the simulation results, the proposed method clearly shows the validity and superiority in respect of computation time and memory space, and that in conjunction with other techniques for indexing, such as color, can provide a powerful framework for image indexing and retrieval.

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CORRELATION BETWEEN BIS-GMA : TEGDMA RATIO AND DEGREE OF CONVERSION IN VARIOUS LAYERS OF COMPOSITE AFTER ADDITIONAL HEAT CURING (수종 복합레진 내의 bis-GMA와 TEGDMA의 구성비가 레진 인레이 법에 의한 부가적 열처리시 복합레진의 표면 및 내부의 중합률 변화에 미치는 영향)

  • Park, Seong-Ho;Chung, Chan-Moon
    • Restorative Dentistry and Endodontics
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    • v.21 no.2
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    • pp.642-651
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    • 1996
  • The purpose of this study was to evaluate the relationship between monomer compositions and the changes in the degree of conversion in the various layers of composites after additional heat curing. Four types of composites and 3 types of inlay ovens were used in this study. Composite was placed in a 4-mm thick teflon mold, and light cured from the top for 60 seconds. Ten samples were prepared for each composite ; 5 of these were additionally heat cured in an inlay oven as the manufacturer recommended. After light curing or light and heat curing, the samples were sectioned into four parts and assigned to groups A, B, C, or D according to their distance from the light source. These sections were then thinned to 50-$70{\mu}m$, and these wafers were analyzed with a Fourier Transform Infrared Spectrometer(FI-IR) to determine the degree of conversion. A standard baseline technique was used to calculate the degree of conversion. $^{13}C$ NMR spectra of bis-GMA, TEGDMA and bis-EMA, were acquired using a Varian Gemini spectrometer operated at 200 MHz. $CDCl_3$ solvent was used for qualitative analysis. The degree of conversion was affected by bis-GMA : TEGDMA ratio but it seemed to be also affected by other factors. When the composites were heat cured, significant increases in the degree of conversion were noted throughout the samples, but the amount of increase differed between materials. Thus, clinical performance of a heat-treated composite inlay may be different depending on materials.

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Molecular Characterization of Dissolved Organic Matter Unveils their Complexity, Origin, and Fate in Glacier and Glacial-Fed Streams and Lakes on the Tibetan Plateau

  • Kim, Min Sung;Zhou, Lei;Choi, Mira;Zhang, Yunlin;Zhou, Yongqiang;Jang, Kyoung-Soon
    • Mass Spectrometry Letters
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    • v.12 no.4
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    • pp.192-199
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    • 2021
  • Alpine glaciers harbor a large quantity of bio-labile dissolved organic matter (DOM), which plays a pivotal role in global carbon cycling as glacial-fed streams are headwaters of numerous large rivers. To understand the complexity, origin, and fate of DOM in glaciers and downstream-linked streams and lakes, we elucidated the molecular composition of DOM in two different Tibetan Plateau glaciers, eight glacial-fed streams and five lakes, using an ultrahigh-resolution 15 Tesla Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer. The compositional changes of the DOM samples revealed that glacier DOM mostly exhibited sulfur-containing organic compounds (CHOS species). We also found that aliphatic formulae contributed more than 50% of the total abundance of assigned molecules in glacier samples, and those compounds were significantly related to CHOS species. The CHO proportions of glacial-fed streams and lakes samples increased with increasing distance from glacial terminals. The relative contribution of terrestrial-derived organics (i.e., lignins and tannins) declined while microbial-originated organics (aliphatics) increased with increasing elevation. This suggested the gradual input of allochthonous materials from non-glacial environment and the degradation of microbe-derived compounds along lower elevations. Alpine glaciers are retreating as a result of climate change and they nourished numerous streams, rivers, and downstream-linked lakes. Therefore, the interpretations of the detailed molecular changes in glacier ice, glacial-fed streams, and alpine lakes on the Tibetan Plateau could provide broad insights for understanding the biogeochemical cycling of glacial DOM and assessing how the nature of DOM impacts fluvial ecosystems.

Resolution Estimation Technique in Gaze Tracking System for HCI (HCI를 위한 시선추적 시스템에서 분해능의 추정기법)

  • Kim, Ki-Bong;Choi, Hyun-Ho
    • Journal of Convergence for Information Technology
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    • v.11 no.1
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    • pp.20-27
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    • 2021
  • Eye tracking is one of the NUI technologies, and it finds out where the user is gazing. This technology allows users to input text or control GUI, and further analyzes the user's gaze so that it can be applied to commercial advertisements. In the eye tracking system, the allowable range varies depending on the quality of the image and the degree of freedom of movement of the user. Therefore, there is a need for a method of estimating the accuracy of eye tracking in advance. The accuracy of eye tracking is greatly affected by how the eye tracking algorithm is implemented in addition to hardware variables. Accordingly, in this paper, we propose a method to estimate how many degrees of gaze changes when the pupil center moves by one pixel by estimating the maximum possible movement distance of the pupil center in the image.

Investigation of continuous and discontinuous contact cases in the contact mechanics of graded materials using analytical method and FEM

  • Yaylaci, Murat;Adiyaman, Gokhan;Oner, Erdal;Birinci, Ahmet
    • Computers and Concrete
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    • v.27 no.3
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    • pp.199-210
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    • 2021
  • The aim of this paper was to examine the continuous and discontinuous contact problems between the functionally graded (FG) layer pressed with a uniformly distributed load and homogeneous half plane using an analytical method and FEM. The FG layer is made of non-homogeneous material with an isotropic stress-strain law with exponentially varying properties. It is assumed that the contact at the FG layer-half plane interface is frictionless, and only the normal tractions can be transmitted along the contacted regions. The body force of the FG layer is considered in the study. The FG layer was positioned on the homogeneous half plane without any bonds. Thus, if the external load was smaller than a certain critical value, the contact between the FG layer and half plane would be continuous. However, when the external load exceeded the critical value, there was a separation between the FG layer and half plane on the finite region, as discontinuous contact. Therefore, there have been some steps taken in this study. Firstly, an analytical solution for continuous and discontinuous contact cases of the problem has been realized using the theory of elasticity and Fourier integral transform techniques. Then, the problem modeled and two-dimensional analysis was carried out by using ANSYS package program based on FEM. Numerical results for initial separation distance and contact stress distributions between the FG layer and homogeneous half plane for continuous contact case; the start and end points of separation and contact stress distributions between the FG layer and homogeneous half plane for discontinuous contact case were provided for various dimensionless quantities including material inhomogeneity, distributed load width, the shear module ratio and load factor for both methods. The results obtained using FEM were compared with the results found using analytical formulation. It was found that the results obtained from analytical formulation were in perfect agreement with the FEM study.

Sympathy, Seeing, and Affective Labor: Mary Shelley's (Re-)Reading of Adam Smith in Frankenstein (공감, 보기, 그리고 감정노동 -『프랑켄스타인』의 아담 스미스 다시 읽기)

  • Shin, Kyung Sook
    • Journal of English Language & Literature
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    • v.58 no.2
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    • pp.189-215
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    • 2012
  • This paper reads Mary Shelley's Frankenstein (1818) in light of the 18th-century understanding of 'sympathy' including those of Hume and Smith and also in light of what Michael Hardt in our century has called "affective labor." I argue that the imaginative capacity and "seeing" are crucial in understanding Smith's idea of 'sympathy.' By showing how the monster's ugliness precludes any human character from sympathizing with him, Mary Shelley exposes that Smith's idea of sympathy fails to maintain social harmony. Mary Shelley revises Smith's 'sympathy' and makes it more radical by suggesting that the active affective labor could bridge the epistemological distance lying between the agent concerned and the impartial spectator. I first read Smith's idea of sympathy as an imaginative capacity which is inevitably influenced by 'seeing' and visual perception. Then I analyze the scenes in which the creature in Frankenstein fails to acquire any human sympathy due to his ugliness, and show how the specular nature of 'sympathy' is disrupted when one party is visually ugly and deformed. I conclude that affective labor and active moral reflection on the part of the spectator need to be provided when the agent concerned is 'ugly' and thus challenges our habitual epistemological boundary. Shelley's re-evaluation of Smith's sympathy, thus, suggests that affective labor may not be something that women alone have to perform, but an ethical practice that concerns all human beings and that can transform the otherwise flawed human capacity for sympathy.