• Title/Summary/Keyword: projection filter

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Particle Filtering based Object Tracking Method using Feedback and Tracking Box Correction (피드백과 박스 보정을 이용한 Particle Filtering 객체추적 방법론)

  • Ahn, Jung-Ho
    • Journal of Satellite, Information and Communications
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    • v.8 no.1
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    • pp.77-82
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    • 2013
  • The object tracking method using particle filtering has been proved successful since it is based on the Monte Carlo simulation to estimate the posterior distribution of the state vector that is nonlinear and non-Gaussian in the real-world situation. In this paper, we present two nobel methods that can improve the performance of the object tracking algorithm based on the particle filtering. First one is the feedback method that replace the low-weighted tracking sample by the estimated state vector in the previous frame. The second one is an tracking box correction method to find an confidence interval of back projection probability on the estimated candidate object area. An sample propagation equation is also presented, which is obtained by experiments. We designed well-organized test data set which reflects various challenging circumstances, and, by using it, experimental results proved that the proposed methods improves the traditional particle filter based object tracking method.

Making 2.5D with Vanishing Point in Photoshop (Photoshop Vanishing Point를 이용한 2.5D 제작에 관한연구)

  • Yoon, Young-Doo;Choi, Eun-Young
    • The Journal of the Korea Contents Association
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    • v.9 no.12
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    • pp.146-153
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    • 2009
  • Thanks to computer graphic technology development, graphic design programming is easily accessible by any home computer user today since it is free from the burdens of complicated 알고리듬 or the expensive graphic tools that were required in the past. The term 알고리듬 2.5 is commonly used by computer graphic designers to refer to 2D, a form of pseudo-3D. In this study, by using 2.5D, which was previously utilized for strengthening visual effects and engine efficiency, together with Adobe Photoshop along with After Effects, I will incorporate these into motion graphics. Today, motion graphics dominate the advertisement and image markets. Since viewers have developed higher expectations, a more dynamic 3D space graphic technology is preferred over the outdated 2D basis. In this study, I will produce a 2.5D image which is generated through a vanishing point filter of Adobe Photoshop and After Effects based on still image information and captured at an angle of Axonometric Projection. Also, I will compare the effectiveness of the production process and camera angle flexibility between the previous 3D process and new 2.5 D process.

Evaluation of Effective and Organ Dose Using PCXMC Program in DUKE Phantom and Added Filter for Computed Radiography System (CR 환경에서의 흉부촬영 시 Duke Phantom과 부가여과를 이용한 유효선량 및 장기선량 평가)

  • Kang, Byung-Sam;Park, Min-Joo;Kim, Seung-Chul
    • Journal of radiological science and technology
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    • v.37 no.1
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    • pp.7-14
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    • 2014
  • By using a Chest Phantom(DUKE Phantom) focusing on dose reduction of diagnostic radiation field with the most use of artificial radiation, and attempt to reduce radiation dose studies technical radiation. Publisher of the main user of the X-ray Radiological technologists, Examine the effect of reducing the radiation dose to apply additional filtering of the X-ray generator. In order to understand the organ dose and effective dose by using the PC-Based Monte Carlo Program(PCXMC) Program, the patient receives, was carried out this research. In this experiment, by applying a complex filter using a copper and Al(aluminum,13) and filtered single of using only aluminum with the condition set, and measures the number of the disk of copper indicated by DUKE Phantom. The combination of the composite filtration and filtration of a single number of the disk of the copper is the same, with the PCXMC 2.0. Program looking combination of additional filtration fewest absorbed dose was calculated effective dose and organ dose. Although depends on the use mAs, The 80 kVp AP projection conditions, it is possible to reduce the effective amount of about 84 % from about 30 % to a maximum at least. The 120 kVp PA projection conditions, it is possible to reduce the effective amount of about 71 % from about 41 % to a maximum of at least. The organ dose, dose reduction rate was different in each organ, but it showed a decrease of dose rate of 30 % to up 100 % at least. Additional filtration was used on the imaging conditions throughout the study. There was no change in terms of video quality at low doses. It was found that using the DUKE Phantom and PCXMC 2.0 Program were suitable to calculate the effect of reducing the effective dose and organ dose.

Vergence control of parallel stereoscopic camera using the binocular disparity information (시차정보를 이용한 수평이동방식 입체영상 카메라의 주시각제어)

  • Kwon, Ki-Chul;Kim, Nam
    • Korean Journal of Optics and Photonics
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    • v.15 no.2
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    • pp.123-129
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    • 2004
  • This paper concerns auto vergence control of a parallel stereoscopic camera through geometrical analysis. In the construction of a parallel stereoscopic camera, we experimentally demonstrated linear relationship between the key object distance and the amount of vergence control. And we proposed a vergence control system for the stereoscopic camera using binocular disparity information. For the real-time calculation of disparity information, the Hybrid Cepstral filter algorithm, with input data acquired from the vertical projection data and from the down sampling data from the source images, was proposed for precision and high speed processing. With the disparity information algorithm and the vergence control of the parallel stereoscopic camera system, the stereoscopic images become more like those of the human eye.

A Spline-Regularized Sinogram Smoothing Method for Filtered Backprojection Tomographic Reconstruction

  • Lee, S.J.;Kim, H.S.
    • Journal of Biomedical Engineering Research
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    • v.22 no.4
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    • pp.311-319
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    • 2001
  • Statistical reconstruction methods in the context of a Bayesian framework have played an important role in emission tomography since they allow to incorporate a priori information into the reconstruction algorithm. Given the ill-posed nature of tomographic inversion and the poor quality of projection data, the Bayesian approach uses regularizers to stabilize solutions by incorporating suitable prior models. In this work we show that, while the quantitative performance of the standard filtered backprojection (FBP) algorithm is not as good as that of Bayesian methods, the application of spline-regularized smoothing to the sinogram space can make the FBP algorithm improve its performance by inheriting the advantages of using the spline priors in Bayesian methods. We first show how to implement the spline-regularized smoothing filter by deriving mathematical relationship between the regularization and the lowpass filtering. We then compare quantitative performance of our new FBP algorithms using the quantitation of bias/variance and the total squared error (TSE) measured over noise trials. Our numerical results show that the second-order spline filter applied to FBP yields the best results in terms of TSE among the three different spline orders considered in our experiments.

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The motion estimation algorithm implemented by the color / shape information of the object in the real-time image (실시간 영상에서 물체의 색/모양 정보를 이용한 움직임 검출 알고리즘 구현)

  • Kim, Nam-Woo;Hur, Chang-Wu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.11
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    • pp.2733-2737
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    • 2014
  • Motion detection according to the movement and the change area detection method according to the background difference and the motion history image for use in a motion estimation technique using a real-time image, the motion detection method according to the optical flow, the back-projection of the histogram of the object to track for motion tracking At the heart of MeanShift center point of the object and the object to track, while used, the size, and the like due to the motion tracking algorithm CamShift, Kalman filter to track with direction. In this paper, we implemented the motion detection algorithm based on color and shape information of the object and verify.

Development of Two Dimensional Filter for the Reconstructive Image Processing (영상 재구성 처리를 위한 이차원 필터의 구성)

  • Lee, Hwang-Soo
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.16 no.6
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    • pp.16-21
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    • 1979
  • Two dimensional kernels which reconstruct a tomographic image from a blurred one formed by simple back-projection are investigated in the frequency domain and their performances are compared. The kernels are derived from a point spread function of the tomographic system and have the form of a ramp filter modified by several window functions to suppress ringings or artifacts in the reconstruction. Computer simulation using computer-generated phantom image data with different filter functions has been carried out. In this simulation, it is found that the computation time for 2-D reconstruction is much less than that of 1-D convolution method by a factor of ten or more whereas the reconstructed image quality of the former is far poorer than the latter. In 2-D reconstruction heavy windowing results in less noisy reconstruction but details smear out in this case. The trade-offs between these points are considered.

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Pupil Detection using PCA and Hough Transform

  • Jang, Kyung-Shik
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.2
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    • pp.21-27
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    • 2017
  • In this paper, we propose a pupil detection method using PCA(principal component analysis) and Hough transform. To reduce error to detect eyebrows as pupil, eyebrows are detected using projection function in eye region and eye region is set to not include the eyebrows. In the eye region, pupil candidates are detected using rank order filter. False candidates are removed by using symmetry. The pupil candidates are grouped into pairs based on geometric constraints. A similarity measure is obtained for two eye of each pair using PCA and hough transform, we select a pair with the smallest similarity measure as final two pupils. The experiments have been performed for 1000 images of the BioID face database. The results show that it achieves the higher detection rate than existing method.

Multichannel Gabor Filler and Log-Polar Transform for Content-Based Image Retrieval (다채널 Gabor 필터와 Log-Polar 변환을 사용한 내용기반 영상 검색)

  • Park, Hyun;Moon, Young-Shik
    • Proceedings of the IEEK Conference
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    • 2000.06c
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    • pp.181-184
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    • 2000
  • In this paper, we propose new features for describing texture images by using multi-channel Gabor filter and log-polar transform based on human visual system (HVS). Gabor features are extracted by the mean and standard deviation of energy in Gabor response, followed by Fourier series extension. Log-polar features are extracted by log-polar transform and projection. The proposed texture descriptor performs reasonably well with less number of features than other texture descriptors, which has been verified by experiments using some texture images of MPEG-7 data set.

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Band Estimation using Third-order Statistics and Wavelet Packet Transform (3차 통계기법과 웨이블릿 패킷 변환을 이용한 대역 추정 알고리즘)

  • 박현석;이종희;남상원
    • Proceedings of the IEEK Conference
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    • 2000.09a
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    • pp.923-926
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    • 2000
  • In this paper we address the problem of detecting and estimating an unknown narrow band signal in a noise interference environment A new practical band estimation method, yielding good performance even in case of finite-length data, is presented. More specifically, wavelet packet transform is utilized to detect the more accurate time-variant band, then we estimate the power from wavelet filter-coefficients of the respective band. Also, third-order cumulants, and projection cross-correlation (PCC) criterion are utilized to achieve an effective SNR improvement for the time-variant band estimation. In case of time variant band estimation, the PCC method yields better performance than the correlation method.

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