• Title/Summary/Keyword: Matrix image

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Fundamental Matrix Estimation and Key Frame Selection for Full 3D Reconstruction Under Circular Motion (회전 영상에서 기본 행렬 추정 및 키 프레임 선택을 이용한 전방향 3차원 영상 재구성)

  • Kim, Sang-Hoon;Seo, Yung-Ho;Kim, Tae-Eun;Choi, Jong-Soo
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.46 no.2
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    • pp.10-23
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    • 2009
  • The fundamental matrix and key frame selection are one of the most important techniques to recover full 3D reconstruction of objects from turntable sequences. This paper proposes a new algorithm that estimates a robust fundamental matrix for camera calibration from uncalibrated images taken under turn-table motion. Single axis turntable motion can be described in terms of its fixed entities. This provides new algorithms for computing the fundamental matrix. From the projective properties of the conics and fundamental matrix the Euclidean 3D coordinates of a point are obtained from geometric locus of the image points trajectories. Experimental results on real and virtual image sequences demonstrate good object reconstructions.

Improved Face Recognition based on 2D-LDA using Weighted Covariance Scatter (가중치가 적용된 공분산을 이용한 2D-LDA 기반의 얼굴인식)

  • Lee, Seokjin;Oh, Chimin;Lee, Chilwoo
    • Journal of Korea Multimedia Society
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    • v.17 no.12
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    • pp.1446-1452
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    • 2014
  • Existing LDA uses the transform matrix that maximizes distance between classes. So we have to convert from an image to one-dimensional vector as training vector. However, in 2D-LDA, we can directly use two-dimensional image itself as training matrix, so that the classification performance can be enhanced about 20% comparing LDA, since the training matrix preserves the spatial information of two-dimensional image. However 2D-LDA uses same calculation schema for transformation matrix and therefore both LDA and 2D-LDA has the heteroscedastic problem which means that the class classification cannot obtain beneficial information of spatial distances of class clusters since LDA uses only data correlation-based covariance matrix of the training data without any reference to distances between classes. In this paper, we propose a new method to apply training matrix of 2D-LDA by using WPS-LDA idea that calculates the reciprocal of distance between classes and apply this weight to between class scatter matrix. The experimental result shows that the discriminating power of proposed 2D-LDA with weighted between class scatter has been improved up to 2% than original 2D-LDA. This method has good performance, especially when the distance between two classes is very close and the dimension of projection axis is low.

IMAGE ENCRYPTION THROUGH THE BIT PLANE DECOMPOSITION

  • Kim, Tae-Sik
    • The Pure and Applied Mathematics
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    • v.11 no.1
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    • pp.1-14
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    • 2004
  • Due to the development of computer network and mobile communications, the security in image data and other related source are very important as in saving or transferring the commercial documents, medical data, and every private picture. Nonetheless, the conventional encryption algorithms are usually focusing on the word message. These methods are too complicated or complex in the respect of image data because they have much more amounts of information to represent. In this sense, we proposed an efficient secret symmetric stream type encryption algorithm which is based on Boolean matrix operation and the characteristic of image data.

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IMAGE RESIZING IN AN ARBITRARY TRANSFORM DOMAIN

  • Oh, Hyung-Suk;Kim, Won-Ha
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.44-48
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    • 2009
  • This paper develops a methodology for resizing image resolutions in an arbitrary block transform domain. To accomplish this, we represent the procedures resizing images in an arbitrary transform domain in the form of matrix multiplications from which the matrix scaling the image resolutions is produce. The experiments showed that the proposed method produces the reliable performances without increasing the computational complexity, compared to conventional methods when applied to various transforms.

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Reconstructing Flaw Image Using Dataset of Full Matrix Capture Technique (Full Matrix Capture 데이터를 이용한 균열 영상화)

  • Lee, Tae-Hun;Kim, Yong-Sik;Lee, Jeong-Seok
    • Journal of the Korean Society for Nondestructive Testing
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    • v.37 no.1
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    • pp.13-20
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    • 2017
  • A conventional phased array ultrasonic system offers the ability to steer an ultrasonic beam by applying independent time delays of individual elements in the array and produce an ultrasonic image. In contrast, full matrix capture (FMC) is a data acquisition process that collects a complete matrix of A-scans from every possible independent transmit-receive combination in a phased array transducer and makes it possible to reconstruct various images that cannot be produced by conventional phased array with the post processing as well as images equivalent to a conventional phased array image. In this paper, a basic algorithm based on the LLL mode total focusing method (TFM) that can image crack type flaws is described. And this technique was applied to reconstruct flaw images from the FMC dataset obtained from the experiments and ultrasonic simulation.

Multi-Description Image Compression Coding Algorithm Based on Depth Learning

  • Yong Zhang;Guoteng Hui;Lei Zhang
    • Journal of Information Processing Systems
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    • v.19 no.2
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    • pp.232-239
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    • 2023
  • Aiming at the poor compression quality of traditional image compression coding (ICC) algorithm, a multi-description ICC algorithm based on depth learning is put forward in this study. In this study, first an image compression algorithm was designed based on multi-description coding theory. Image compression samples were collected, and the measurement matrix was calculated. Then, it processed the multi-description ICC sample set by using the convolutional self-coding neural system in depth learning. Compressing the wavelet coefficients after coding and synthesizing the multi-description image band sparse matrix obtained the multi-description ICC sequence. Averaging the multi-description image coding data in accordance with the effective single point's position could finally realize the compression coding of multi-description images. According to experimental results, the designed algorithm consumes less time for image compression, and exhibits better image compression quality and better image reconstruction effect.

Determinant Eigenvalue and Inverse Matrix of a Tridiagonal Matrix (삼대각선행열의 행열식 고유값 및 역행열)

  • Lee, Doo-Soo
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.23 no.4
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    • pp.455-459
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    • 1986
  • A large set of linear equations which arise in many applications, such as in digital signal processing, image filtering, estimation theory, numerical analysis, etc. involve the problem of a tridiagonal matrix. In this paper, the determinant, eigenvalue and inverse matrix of a tridiagoanl matrix are analytically evaluated.

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Image Analysis and DC Conductivity Measurement for the Evaluation of Carbon Nanotube Distribution in Cement Matrix

  • Nam, I.W.;Lee, H.K.
    • International Journal of Concrete Structures and Materials
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    • v.9 no.4
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    • pp.427-438
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    • 2015
  • The present work proposes a new image analysis method for the evaluation of the multi-walled carbon nanotube (MWNT) distribution in a cement matrix. In this method, white cement was used instead of ordinary Portland cement with MWNT in an effort to differentiate MWNT from the cement matrix. In addition, MWNT-embedded cement composites were fabricated under different flows of fresh composite mixtures, incorporating a constant MWNT content (0.6 wt%) to verify correlation between the MWNT distribution and flow. The image analysis demonstrated that the MWNT distribution was significantly enhanced in the composites fabricated under a low flow condition, and DC conductivity results revealed the dramatic increase in the conductivity of the composites fabricated under the same condition, which supported the image analysis results. The composites were also prepared under the low flow condition (114 mm < flow < 126 mm), incorporating various MWNT contents. The image analysis of the composites revealed an increase in the planar occupation ratio of MWNT, and DC conductivity results exhibited dramatic increase in the conductivity (percolation phenomena) as the MWNT content increased. The image analysis and DC conductivity results indicated that fabrication of the composites under the low flow condition was an effective way to enhance the MWNT distribution.

Mosaics Image Generation based on Mellin Transform (멜린 변환을 이용한 모자이크 이미지 생성)

  • 이지현;양황규
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.8
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    • pp.1785-1791
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    • 2003
  • This paper presents the mosaic method that the video sequence with shift and rotation information after Mellin Transform. The results are used to compute the projection matrix for each image registration. So before registration, we process camera calibration in order to reduce the image warp by camera and then compute the global projection matrix for image registration for reducing errors from rut image to last image. This paper describes the mosaic method that compute duplication and movement information quickly and robust noise using projection matrix on Mellin Transform.

Correspondence Estimation for Wide Area Watching Camera System (광역관찰 카메라 시스템을 위한 카메라의 대응관계 계산)

  • 이동휘;최승현;이칠우
    • Proceedings of the IEEK Conference
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    • 2001.09a
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    • pp.415-418
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    • 2001
  • The automatic construction of large, high-resolution image mosaics is an active area of reasearch in the fields of photogrammetry, computer vision, image processing, and computer graphics. In this study, we describe a automatic mosaicing method that makes a panorama from images by placing camera in a emitted-grid. In the images captured by cameras, there must be a matched area and the area is in the particular area of the image. Initial transformation matrix, there(ore, is calculated from points searched in the partial area. It is possible to find best transformation matrix by Levenberg-Marquardt method. Finally, each images are multiplied by blending function and stitched by the transformation matrix to complete panoramic image.

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