• Title/Summary/Keyword: 코드북

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ROI Based Object Extraction Using Features of Depth and Color Images (깊이와 칼라 영상의 특징을 사용한 ROI 기반 객체 추출)

  • Ryu, Ga-Ae;Jang, Ho-Wook;Kim, Yoo-Sung;Yoo, Kwan-Hee
    • The Journal of the Korea Contents Association
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    • v.16 no.8
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    • pp.395-403
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    • 2016
  • Recently, Image processing has been used in many areas. In the image processing techniques that a lot of research is tracking of moving object in real time. There are a number of popular methods for tracking an object such as HOG(Histogram of Oriented Gradients) to track pedestrians, and Codebook to subtract background. However, object extraction has difficulty because that a moving object has dynamic background in the image, and occurs severe lighting changes. In this paper, we propose a method of object extraction using depth image and color image features based on ROI(Region of Interest). First of all, we look for the feature points using the color image after setting the ROI a range to find the location of object in depth image. And we are extracting an object by creating a new contour using the convex hull point of object and the feature points. Finally, we compare the proposed method with the existing methods to find out how accurate extracting the object is.

Motion Compensated Difference Image CVQ Using the Characteristics of Motion Vectors and Compensated Blocks (움직임 벡터 및 보상 블록의 특성을 이용한 움직임 보상된 차영상 CVQ)

  • Choi, Jung-Hyun;Lee, Kyeong-Hwan;Lee, Bub-Ki;Cheong, Won-Sik;Kim, Kyoung-Kyoo;Kim, Duk-Gyoo
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.37 no.2
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    • pp.15-20
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    • 2000
  • In this paper, we presents a new MCDI(motion compensated difference image) coding method using CVQ(classifled vector quantization) whoes MCD(motion compensated difference) block is classified by proposed classifier using motion vector and compensated block The variance of MCD block is closely related with the magnitude of motion vector as well as the variance of compensated block, so using this property, we propose a new classifier. This scheme has no side information of the classifier what sub-codebook is selected, and simulation results show that the proposed method exhibits a good performance even when compared with a conventional method that requires classification bits.

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A Study on Isolated Word Recognition using Improved Multisection Vector Quantization Recognition System (개선된 MSVQ 인식 시스템을 이용한 단독어 인식에 관한 연구)

  • An, Tae-Ok;Kim, Nam-Joong;Song, Chul;Kim, Soon-Hyeob
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.16 no.2
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    • pp.196-205
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    • 1991
  • This paper is a study on the isolated word recognition of speaker independent which proposes to newly improved MSVQ(multisection vector quantization) recognition system which improve the classical MSVQ recognition system. It is a difference that test pattern has on more section than reference pattern in recognition system 146 DDD area names are selected as recognition vocabulary. 12th LPC cepstral coefficients is used as feature parameter. and when codebook is generated, MINSUM and MINMAX are used in finding the centroid. According to the experiment result. it is proved that this method is better than VQ(vector quantization) recognition methods, DTW(dynamic time warping) pattern matching methods and classical MSVQ methods for recognition rate and recognition time.

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An Algorithm on Improving a Pitch Searching by Energy Compensation in a Frame for Vocoder (보코더에서 프레임별 에너지 보상에 의한 피치검색 성능 개선에 관한 연구)

  • Baek, Geum-Ran;Min, So-Yeon;Bae, Myung-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.7
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    • pp.3188-3193
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    • 2012
  • It is important to search a pitch for vocoder. The major drawback to vocoders is their large computational requirements in searching a pitch and a codebook. In this paper, a simple method is proposed to improve the pitch searching process in the pitch filter almost without degradation of quality. The period of speech signal is emphasized by using Dual Pulse technique, the same type of autocorrelation method, in pitch search. Sometimes the incorrect pitch can be obtained by halving, doubling and trifling, To solve it, before searching a pitch, we estimate energy rate in a frame and compensate envelop of signal with it. By using the proposed algorithm in pitch search, its required computation are reduced and searching pitch is improved.

Performance Evaluation of Beamforming Scheme in Millimeter Wave Wireless Communication System (밀리미터파 무선통신 시스템에서의 빔포밍 기법 성능 평가)

  • Nguyen, Thanh Ngoc;Jeon, Taehyun
    • Journal of Satellite, Information and Communications
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    • v.11 no.3
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    • pp.133-137
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    • 2016
  • Millimeter wave wireless communication systems, especially those targeting indoor high rate data transfer, have a strong requirement for high quality wireless link. Unfortunately, in this frequency band, the electromagnetic wave has to sustain the high propagation loss caused by the smaller wavelengths. In this scenario, beamforming technique, which enhances the link quality by focusing the radiation power on a direction, becomes one of the most important techniques in millimeter wave band wireless communication. In recent year, there been conducted many research on beamforming to improve the performance of wireless system. In this paper, we evaluate the performance of a simplified codebook-based beamforming scheme which is based on multiple-procedure and three-state beam selection. The simplified scheme significantly reduces beamforming setup time, comparing to the exhaustive searching, two-level searching adopted in IEEE 802.15.3c standard, and also conventional multi-level scheme.

Hole-Filling Method Using Extrapolated Spatio-temporal Background Information (추정된 시공간 배경 정보를 이용한 홀채움 방식)

  • Kim, Beomsu;Nguyen, Tien Dat;Hong, Min-Cheol
    • Journal of the Institute of Electronics and Information Engineers
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    • v.54 no.8
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    • pp.67-80
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    • 2017
  • This paper presents a hole-filling method using extrapolated spatio-temporal background information to obtain a synthesized view. A new temporal background model using non-overlapped patch based background codebook is introduced to extrapolate temporal background information In addition, a depth-map driven spatial local background estimation is addressed to define spatial background constraints that represent the lower and upper bounds of a background candidate. Background holes are filled by comparing the similarities between the temporal background information and the spatial background constraints. Additionally, a depth map-based ghost removal filter is described to solve the problem of the non-fit between a color image and the corresponding depth map of a virtual view after 3-D warping. Finally, an inpainting is applied to fill in the remaining holes with the priority function that includes a new depth term. The experimental results demonstrated that the proposed method led to results that promised subjective and objective improvement over the state-of-the-art methods.

Background Modeling for Object Detection from Tidal Flat Images (갯벌 영상에서 객체 검출을 위한 배경 모델링)

  • Park, Sang-Hyun
    • The Journal of the Korea institute of electronic communication sciences
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    • v.15 no.3
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    • pp.563-572
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    • 2020
  • Tidal flats provide important indicators that inform the condition of the environment, so we need to monitor them systematically. Currently, the projects to monitor tidal flats by periodically observing the creatures in tidal flats are underway. Still, it is done in a way that people observe directly, so it is not systematic and efficient. In this paper, we propose a background modeling method for tidal flat images that can be applied to a system that automatically monitors creatures living in tidal flats using sensor network technology. The application of sensor network technology makes it difficult to collect enough images due to the limitation of transmission capacity. Therefore, in this paper, we propose a method to effectively model the background and generate foreground maps by reflecting the characteristics of tidal flat images in the situation where the number of images to be used for analysis is small. Experimental results show that the proposed method models the background of a tidal flat image easily and accurately.

Performance of OFDM using Beam-switching and Space-Time coding in Wireless Personal Area Network (무선 개인 영역망 환경에서 빔 스위칭과 시공간부호를 적용한 OFDM 전송방식의 성능)

  • Yoon, Seok-Hyun
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.47 no.7
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    • pp.85-92
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    • 2010
  • In this paper, we consider the orthogonal frequency division multiplexing (OFDM) based transmission incoorperating with beam-switching and space-time coding. Specifically, we consider three configurations; (1) the beamforming technique, (2) the spatial diversity technique and (3) their combination and evaluate the performance in wireless personal area network (WPAN) environment. For the beam-forming technique, we consider the beam-switching which is performed at RF front-end with a pre-defined set of beams and for the space-time coding, we consider the Alamauti scheme with antenna selection. For the combined scheme, we divide the antennas used into two group to generate two independent beams and apply the two-antenna Alamauti scheme over the two beams. For these three configurations, performance is evaluated in terms of the SNR gain.

Face Recognition using Vector Quantizer in Eigenspace (아이겐공간에서 벡터 양자기를 이용한 얼굴인식)

  • 임동철;이행세;최태영
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.5
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    • pp.185-192
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    • 2004
  • This paper presents face recognition using vector quantization in the eigenspace of the faces. The existing eigenface method is not enough for representing the variations of faces. For making up for its defects, the proposed method use a clustering of feature vectors by vector quantization in eigenspace of the faces. In the trainning stage, the face images are transformed the points in the eigenspace by eigeface(eigenvetor) and we represent a set of points for each people as the centroids of vector quantizer. In the recognition stage, the vector quantizer finds the centroid having the minimum quantization error between feature vector of input image and centriods of database. The experiments are performed by 600 faces in Faces94 database. The existing eigenface method has minimum 64 miss-recognition and the proposed method has minimum 20 miss-recognition when we use 4 codevectors. In conclusion, the proposed method is a effective method that improves recognition rate through overcoming the variation of faces.

A MIMO LTE Precoding Codebook Based on Fast Diagonal Weighted Matrices (고속 대각 하중 행렬을 이용한 MIMO LTE 프리코딩 코드북)

  • Park, Ju-Yong;Peng, Bu Shi;Lee, Moon-Ho
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.49 no.3
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    • pp.14-26
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    • 2012
  • In this paper, a fast diagonal-weighted Jacket matrices (DWJMs) is proposed to have the orthogonal architecture. We develop the successive DWJM to reduce the computational load while factorizing the large-order DWJMs into the low-order sparse matrices with the fast algorithms. The proposed DWJM is then applied to the precoding multiple-input and multiple output (MIMO) wireless communications because of its diagonal-weighted framework with element-wise inverse characteristics. Based on the properties of the DWJM, the DWJM can be used as alternative open loop cyclic delay diversity (CDD) precoding, which has recently become part of the cellular communications systems. Performance of the DWJM-based precoding system is verified for orthogonal space-time block code (OSTBC) MIMO LTE systems.