• 제목/요약/키워드: Transform

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Mellin Transform에 기반한 파노라믹 영상 생성을 위한 이미지 접합 (Image Registration for Panoramic Image Using Mellin Transform)

  • 이지현;송복득;윤태수;양황규
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2002년도 추계학술발표논문집 (상)
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    • pp.665-668
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    • 2002
  • 본 논문은 카메라를 수평이동시켜 얻어진 영상을 Mellin Transform을 이용하여 파노라마 이미지를 구성하는 방법을 제안한다. 일반적으로 카메라로부터 얻어진 동영상은 각 프레임 사이에 많은 시간적, 공간적 정보가 중복되어 있다. 이러한 중복 정보는 모자이크 방법 중의 하나인 파노라믹 기법을 사용하여 줄일 수 있다. 지금까지의 제안된 이미지의 중복성을 찾는 알고리즘들은 노이즈에 지나치게 민감하거나 중복성을 계산하는 데 있어 시간이 많이 소모되는 단점이 있었다. 따라서 본 논문에서는 Mellin Transform 을 사용하여 노이즈에 덜 민감하고 빠른 시간에 이미지의 중복 정보를 찾아내는 방법을 제안한다. Mellin Transform을 이용하여 생성된 파노라마 영상은 이미지의 이동정보를 쉽게 구할 있어 동영상에서 움직이는 물체를 추적하거나 추정이 가능하여 물체 tracking 영역에 응용될 수 있을 것으로 보이며 또한 앞으로 현실감 있는 가상현실의 배경 생성에 도움이 될 것으로 생각된다.

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QP 방법과 McClellan 변환을 이용한 2차원 FIR Elliptic 필터 설계에 관한 연구 (A Study on QP Method and Two Dimensional FIR Elliptic Filter Design with McClellan Transform)

  • 김남수;이상준;김남호
    • 융합신호처리학회 학술대회논문집
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    • 한국신호처리시스템학회 2003년도 하계학술대회 논문집
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    • pp.268-271
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    • 2003
  • There are several methods for the design of 2D filter. Notable among them is McClellan transform method. This transform allows us to obtain a high order 2D FIR filter through mapping the 1D frequency points of a 1D prototype FIR filter onto 2D frequency contours. We design 2D filter using this transform. Then we notice for mapping deviation of the 2D filter. In this paper, Quadratic programming (QP) method allows us to obtain coefficients of McClellan transform. Then we compare deviation of QP method with least-squares(LS) method. Elliptic filter is used for comparison. The optimal cutoff frequencies of a 1D filter are obtained directly from the QP method. Also several problem of LS method are solved.

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Low-Complexity Sub-Pixel Motion Estimation Utilizing Shifting Matrix in Transform Domain

  • Ryu, Chul;Shin, Jae-Young;Park, Eun-Chan
    • Journal of Electrical Engineering and Technology
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    • 제11권4호
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    • pp.1020-1026
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    • 2016
  • Motion estimation (ME) algorithms supporting quarter-pixel accuracy have been recently introduced to retain detailed motion information for high quality of video in the state-of-the-art video compression standard of H.264/AVC. Conventional sub-pixel ME algorithms in the spatial domain are faced with a common problem of computational complexity because of embedded interpolation schemes. This paper proposes a low-complexity sub-pixel motion estimation algorithm in the transform domain utilizing shifting matrix. Simulations are performed to compare the performances of spatial-domain ME algorithms and transform-domain ME algorithms in terms of peak signal-to-noise ratio (PSNR) and the number of bits per frame. Simulation results confirm that the transform-domain approach not only improves the video quality and the compression efficiency, but also remarkably alleviates the computational complexity, compared to the spatial-domain approach.

A comparison of inverse transform and composition methods of data simulation from the Lindley distribution

  • Okwuokenye, Macaulay;Peace, Karl E.
    • Communications for Statistical Applications and Methods
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    • 제23권6호
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    • pp.517-529
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    • 2016
  • This study compares the inverse transform and the composition methods for generating data from the Lindley distribution. The expression for the inverse of the distribution function for the Lindley distribution does not exist in closed form. Hence, authors of many empirical studies on the Lindley distribution used methods for generating Lindley variates other than the inverse transform. We generated data from the Lindley distribution using the inverse transform approach by obtaining the Lindley variates numerically; we also generated data from this distribution using the composition approach. Following the generation of the Lindley variates using these two methods, we compare some statistical properties of the estimates of the Lindley model parameters based on the generated data. We conclude that the two methods produce similar results.

2차원 영상에서 패턴매칭을 이용한 3차원 물체의 변환정보 추정 (The Estimation of the Transform Parameters Using the Pattern Matching with 2D Images)

  • 조택동;이호영;양상민
    • 한국정밀공학회지
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    • 제21권7호
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    • pp.83-91
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    • 2004
  • The determination of camera position and orientation from known correspondences of 3D reference points and their images is known as pose estimation in computer vision or space resection in photogrammetry. This paper discusses estimation of transform parameters using the pattern matching method with 2D images only. In general, the 3D reference points or lines are needed to find out the 3D transform parameters, but this method is applied without the 3D reference points or lines. It uses only two images to find out the transform parameters between two image. The algorithm is simulated using Visual C++ on Windows 98.

Wavelet Transform을 이용한 P파 검출에 관한 연구 (P-wave Detection Using Wavelet Transform)

  • 윤영로;장원석
    • 대한의용생체공학회:의공학회지
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    • 제17권4호
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    • pp.507-514
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    • 1996
  • The automated ECG diagnostic systems in hospital have a low P-wave detection capacity in case of some diseases like conduction block. The purpose of this study is to improve the P-wave detection ca- pacity using wavelet transform. The first procedure is to remove baseline drift by subtracting the median filtered signal from the original signal. The second procedure is to cancel ECG's QRS-T complex from median filtered signal to get P-wave candidate. Before we subtracted the templete from QRS-T complex, we estimated the best matching between templete and QRS-T complex to minimize the error. Then, wavelet transform was applied to confirm P-wave. In particular, haiti wavelet was used to magnify P-wave that consisted of low frequency components and to reject high frequency noise of QRS-T complex cancelled signal. Finally, p-wave was discriminated and confirmed by threshold value. By using this method, We can got the around 95.1% P-wave detection. It was compared with contextual information.

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A TRANSLATION THEOREM FOR THE GENERALIZED FOURIER-FEYNMAN TRANSFORM ASSOCIATED WITH GAUSSIAN PROCESS ON FUNCTION SPACE

  • Chang, Seung Jun;Choi, Jae Gil;Ko, Ae Young
    • 대한수학회지
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    • 제53권5호
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    • pp.991-1017
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    • 2016
  • In this paper we define a generalized analytic Fourier-Feynman transform associated with Gaussian process on the function space $C_{a,b}[0,T]$. We establish the existence of the generalized analytic Fourier-Feynman transform for certain bounded functionals on $C_{a,b}[0,T]$. We then proceed to establish a translation theorem for the generalized transform associated with Gaussian process.

SOME EXPRESSIONS FOR THE INVERSE INTEGRAL TRANSFORM VIA THE TRANSLATION THEOREM ON FUNCTION SPACE

  • Chang, Seung Jun;Chung, Hyun Soo
    • 대한수학회지
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    • 제53권6호
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    • pp.1261-1273
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    • 2016
  • In this paper, we analyze the necessary and sufficient condition introduced in [5]: that a functional F in $L^2(C_{a,b}[0,T])$ has an integral transform ${\mathcal{F}}_{{\gamma},{\beta}}F$, also belonging to $L^2(C_{a,b}[0,T])$. We then establish the inverse integral transforms of the functionals in $L^2(C_{a,b}[0,T])$ and then examine various properties with respect to the inverse integral transforms via the translation theorem. Several possible outcomes are presented as remarks. Our approach is a new method to solve some difficulties with respect to the inverse integral transform.

정수 직교 겹침 변환을 이용한 이미지 압축 (Image Compression Using Integer Lapped Orthogonal Transform)

  • 이상호;장준호;김영섭;임상민
    • 반도체디스플레이기술학회지
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    • 제8권3호
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    • pp.45-50
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    • 2009
  • Recently, block-based transforms, like discrete cosine transform (DCT), have been widely used in image and video coding standards, but block-based transforms have a weak point with blocking effect. However, the integer lapped orthogonal transform (ILOT) is a tool for block-based coding with bases functions that overlap near blocks, so it has a strong point against blocking effect. Although it has slightly higher arithmetic complexity than the DCT, the coding gain is significantly higher with much less blocking artifacts. This paper introduces the integer lapped orthogonal transforms and discrete cosine transform. And we compare the performance of DCT with ILOT which is proposed a new efficient method for image coding applications.

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Accurate Segmentation Algorithm of Video Dynamic Background Image Based on Improved Wavelet Transform

  • Ming, Ming
    • Journal of Information Processing Systems
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    • 제18권5호
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    • pp.711-718
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    • 2022
  • In this paper, an accurate segmentation algorithm of video dynamic background image (VDBI) based on improved wavelet transform is proposed. Based on the smooth processing of VDBI, the traditional wavelet transform process is improved, and the two-layer decomposition of dynamic image is realized by using two-dimensional wavelet transform. On the basis of decomposition results and information enhancement processing, image features are detected, feature points are extracted, and quantum ant colony algorithm is adopted to complete accurate segmentation of the image. The maximum SNR of the output results of the proposed algorithm can reach 73.67 dB, the maximum time of the segmentation process is only 7 seconds, the segmentation accuracy shows a trend of decreasing first and then increasing, and the global maximum value can reach 97%, indicating that the proposed algorithm effectively achieves the design expectation.