• Title/Summary/Keyword: Transform Coding

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Implementation of CORBA based Spatial Data Provider for Interoperability (상호운용을 지원하는 코바 기반 공간 데이터 제공자의 설계 및 구현)

  • Kim, Min-Seok;An, Kyoung-Hwan;Hong, Bong-Hee
    • Journal of Korea Spatial Information System Society
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    • v.1 no.2 s.2
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    • pp.33-46
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    • 1999
  • In distributed computing platforms like CORBA, wrappers are used to integrate heterogeneous systems or databases. A spatial data provider is one of the wrappers because it provides clients with uniform access interfaces to diverse data sources. The individual implementation of spatial data providers for each of different data sources is not efficient because of redundant coding of the wrapper modules. This paper presents a new architecture of the spatial data provider which consists of two layered objects : independent wrapper components and dependent wrapper components. Independent wrapper components would be reused for implementing a new data provider for a new data source, which dependent wrapper components should be newly coded for every data source. This paper furthermore discussed the issues of implementing the representation of query results in the middleware. There are two methods of keeping query results in the middleware. One is to keep query results as non-CORBA objects and the other is to transform query results into CORBA objects. The evaluation of the above two methods shows that the cost of making CORBA objects is very expensive.

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Error Concealment Method for MPEG-4 Video in Wireless Environment (무선환경에서 MPEG-4 영상의 오류은닉 방법)

  • Park, Sun-Young;Song, Joon-Ho;Moon, Joo-Hee
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.39 no.6
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    • pp.641-651
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    • 2002
  • Recently, many advanced video application services over the mobile wireless networks have required a transcoder which can efficiently reduce the size of compressed video bitstreams. The transcoder can be worked in either the spatial domain or the DCT domain. In this paper, we propose a new fast hybrid-type transcoder which can efficiently reduce the frame size with keeping the visual quality. The proposed scheme consists of two major processes: a transform domain process and a spatial domain process. We also propose a scheme for coding mode selection and motion vector refinement. Experimental results show that our approach can reduce the computational complexity more than any other conventional spatial-domain transcoder with keeping the visual quality.

A Self-regulated Learning Model Development in Computer Programming Education (컴퓨터 프로그램 교육에서 자기조절 학습 모델 개발)

  • Kim, Kapsu
    • Journal of The Korean Association of Information Education
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    • v.19 no.1
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    • pp.21-30
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    • 2015
  • Information and knowledge society in the 21st century computer education is very important. Computer programming education in computer education is very important. There are very few teaching and learning model of computer programming education. In this paper, we develop a self-regulated learning model for students to be self-regulated learning. In this study, we propose self-regulated learning elements, a self-regulated learning steps and self-regulated learning modele. Self-regulated learning elements are task level, generalized level, and efficiency level. Self-regulated learning phases are problem understanding, design, and coding, testing, and maintenance. Self-regulated learning models are to copy, to modify, create, and to challenge. The results of this study are as follows. At Correlations between learning elements and achievement, generalized level, and efficiency level are higher than the task level. At Correlations between learning and achievement, Understanding and design stages are higher than the other stages. At Correlations between learning model and achievement, to transform, to create, and to challenge are higher than to copy.

Lossless Color Image Compression using Inter-channel Correlation (채널 간 상관관계를 이용한 무손실 컬러 이미지 압축)

  • Kim, Se-Yun;Cho, Nam-Ik
    • Journal of Broadcast Engineering
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    • v.16 no.6
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    • pp.962-968
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    • 2011
  • The conventional lossless compression of color images is to apply a compression method to each of color components separately, without considering the channel correlation. There had been several methods that consider the channel correlation, but they were confined to the compression of satellite or aerial images only, and the performance of these algorithms to general photos is not satisfactory. This paper proposes a new lossless color image compression method that exploits the correlation between the color components. Specifically, asymmetric sampling is applied to transform an image into mosaic image and the rest, which are compressed separately. By using the information from the compressed mosaic image, the rest images are predicted for further reducing the information to be compressed. Experimental results show that the proposed method improves the compression performance by 35% over the conventional separate compression methods and 10% over the existing methods that exploit the channel correlation.

Functional Expression of Nicotiana tabacum Acetolactate Synthase Gene in Escherichia coli

  • Kim, Hyun-Ju;Chang, Soo-Ik
    • BMB Reports
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    • v.28 no.3
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    • pp.265-270
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    • 1995
  • Acetolactate synthase (ALS, EC 4.1.3.18) is the first common enzyme in the biosynthesis of leucine, isoleucine, and valine. It is the target enzyme for several classes of herbicides, including the sulfonylureas, the imidazolinones, the triazolopyrimidines, the pyrimidyl-oxy-benzoates and the pyrimidyl-thio-benzens. The sulfonylurea-resistant ALS gene (SurB) from Nicotiana tabaccum [Lee et al. (1988) The EMBO J. 7, 1241-1248] was cloned into the bacterial expression plasmid pT7-7. The resulting recombinant plasmid pT7-ALS was used to transform an ALS-deficient Escherichia coli strain MF2000. MF2000 cells transformed with pT7-ALS grew in the absence of valine and isoleucine. ALS activities of 0.042 and 0.0002 ${\mu}mol/min/mg$ protein were observed in the crude extracts prepared from MF2000 cells transformed with plasmids pT7-ALS and pT7-7, respectively. In addition, the former crude extract containing mutant ALS was insensitive to inhibition by K11570, a new chemical class of herbicides. $IC_{50}$ values for K11570 were $0.13{\pm}0.01$ mM. For comparison, a plasmid pTATX containing the wild-type Arabidopsis thaliana ALS coding sequences was also expressed in MF2000. ALS activities of 0.037 ${\mu}mol/min/mg$ protein were observed, and the wild type ALS was sensitive to two different classes of herbicides, K11570 and ALLY, a sulfonylurea. $IC_{50}$ values for K11570 and ALLY were $0.63{\pm}0.07$ and $80{\pm}5.6$ nM, respectively. Thus, the results suggest that the sulfonylurea-resistant tobacco ALS was functionally expressed in the bacteria, and that K11570 herbicides bind to the regulatoty site of ALS enzymes.

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Compression Method for Digital Hologram using Motion Prediction Method in Frequency-domain (주파수 영역에서 움직임 예측을 이용한 디지털 홀로그램 압축 기법)

  • Choi, Hyun-Jun;Bae, Yun-Jin;Seo, Young-Ho;Kang, Chang-Soo;Kim, Dong-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.9
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    • pp.2091-2098
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    • 2010
  • This paper proposes a hologram data compression scheme that uses the existing image/video compression techniques, in which the existing techniques are modified appropriately to fit to the characteristics of hologram. In this paper we use CGH as the hologram data. The proposed scheme uses the generation characteristics of a CGH to consist of a pre-processing, spatial segmentation of a CGH, frequency-transformation with 2D-DCT (2-dimensional discrete cosine transform), and motion estimation and residual image generation in the frequency-domain. It uses H.264/AVC, the lossless compressor BinHex, and a linear quantizer that we have made. From the experiments the proposed scheme showed the image quality of about 25.4 dB at the compression ratio of 10:1 and about 16.5dB at 90:1 compression ratio.

A Study on the Frequency Scaling Methods Using LSP Parameters Distribution Characteristics (LSP 파라미터 분포특성을 이용한 주파수대역 조절법에 관한 연구)

  • 민소연;배명진
    • The Journal of the Acoustical Society of Korea
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    • v.21 no.3
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    • pp.304-309
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    • 2002
  • We propose the computation reduction method of real root method that is mainly used in the CELP (Code Excited Linear Prediction) vocoder. The real root method is that if polynomial equations have the real roots, we are able to find those and transform them into LSP. However, this method takes much time to compute, because the root searching is processed sequentially in frequency region. In this paper, to reduce the computation time of real root, we compare the real root method with two methods. In first method, we use the mal scale of searching frequency region that is linear below 1 kHz and logarithmic above. In second method, The searching frequency region and searching interval are ordered by each coefficient's distribution. In order to compare real root method with proposed methods, we measured the following two. First, we compared the position of transformed LSP (Line Spectrum Pairs) parameters in the proposed methods with these of real root method. Second, we measured how long computation time is reduced. The experimental results of both methods that the searching time was reduced by about 47% in average without the change of LSP parameters.

Texture Classification Using Rotation Invariant Local Directional Pattern (Rotation Invariant Local Directional Pattern을 이용한 텍스처 분류 방법)

  • Lee, Tae Hwan;Chae, Ok Sam
    • Convergence Security Journal
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    • v.17 no.3
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    • pp.21-29
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    • 2017
  • Accurate encoding of local patterns is a very important factor in texture classification. However, LBP based methods w idely studied have fundamental problems that are vulnerable to noise. Recently, LDP method using edge response and dire ction information was proposed in facial expression recognition. LDP is more robust to noise than LBP and can accommod ate more information in it's pattern code, but it has drawbacks that it is sensitive to rotation transforms that are critical to texture classification. In this paper, we propose a new local pattern coding method called Rotation Invariant Local Direc tional Pattern, which combines rotation-invariant transform to LDP. To prove the texture classification performance of the proposed method in this paper, texture classification was performed on the widely used UIUC and CUReT datasets. As a result, the proposed RILDP method showed better performance than the existing methods.

Performance Analysis of DVC Scheme with Adaptive Gray Code for Frame Difference Signal (화면 간 차이신호에 대한 적응적 그레이코드를 이용한 분산 비디오 부호화 기법의 성능 분석)

  • Kim, Jin-Soo;Kim, Jae-Gon;Choi, Hae-Chul
    • Journal of Broadcast Engineering
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    • v.17 no.5
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    • pp.876-890
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    • 2012
  • In this paper, we investigated the performances of the distributed video codec with adaptive Gray code to apply for frame-difference signal. That is, the best cases and the worst cases were analyzed and compared by considering the statistical characteristics of the frame difference signal in view of the Gray code allocation. Through computer simulations, if 9-bit data for frame difference signal is generated for luminance signal with 8-bit definition and so n-bit is allocated to the quantized coefficient, we were able to find the best method to reduce the virtual channel noise by adding $256+2^{9-n-1}$ to the frame difference signal. Through computer simulation with test video sequences, it was shown that the performance difference between the best cases and the worst cases is larger than about 1.5dB at same rate. It is expected that the results in this paper are applicable for the transform-domain scheme as well as the pixel-domain scheme.

ASIP Design for Real-Time Processing of H.264 (실시간 H.264/AVC 처리를 위한 ASIP설계)

  • Kim, Jin-Soo;SunWoo, Myung-Hoon
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.44 no.5
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    • pp.12-19
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    • 2007
  • This paper presents an ASIP(Application Specific Instruction Set Processor) for implementation of H.264/AVC, called VSIP(Video Specific Instruction-set Processor). The proposed VSIP has novel instructions and optimized hardware architectures for specific applications, such as intra prediction, in-loop deblocking filter, integer transform, etc. Moreover, VSIP has hardware accelerators for computation intensive parts in video signal processing, such as inter prediction and entropy coding. The VSIP has much smaller area and can dramatically reduce the number of memory access compared with commercial DSP chips, which result in low power consumption. The proposed VSIP can efficiently perform in real-time video processing and it can support various profiles and standards.