• Title/Summary/Keyword: lookup table

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Performance Improvement of Binary MQ Arithmetic Coder (2진 MQ 산술부호기의 성능 개선)

  • Ko, Hyung Hwa;Seo, Seok Yong
    • Journal of Advanced Navigation Technology
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    • v.19 no.6
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    • pp.614-622
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    • 2015
  • Binary MQ arithmetic coding is widely used recently as a basic entropy coder in multimedia coding system. MQ coder esteems high in compression efficiency to be used in JBIG2 and JPEG2000. The importance of arithmetic coding is increasing after it is adopted as an unique entropy coder in HEVC standard. In the binary MQ coder, arithmetic approximation without multiplication is used in the process of recursive subdivision of range interval. Because of the MPS/LPS exchange activity happened in MQ coder, output byte tends to increase. This paper proposes an enhanced binary MQ arithmetic coder to make use of a lookup table for AQe using quantization skill in order to reduce the deficiency. Experimental results show that about 4% improvement of compression in case of JBIG2 for bi-level image compression standard. And also, about 1% improvement of compression ratio is obtained in case of lossless JPEG2000 coding. For the lossy JPEG2000 coding, about 1% improvement of PSNR at the same compression ratio. Additionally, computational complexity is not increasing.

Efficient All-to-All Personalized Communication Algorithms in Wormhole Networks (웜홀 방식 망에서의 효율적인 완전교환 통신 알고리즘)

  • Kim, Si-Gwan;Maeng, Seung-Ryoul;Cho, Jung-Wan
    • Journal of KIISE:Computer Systems and Theory
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    • v.27 no.5
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    • pp.464-474
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    • 2000
  • All-to-all personalized communication, or complete exchange, is at the heart of numerous applications, such as matrix transposition, fast Fourier Transform(FFT), and distributed table lookup.We present an efficient all-to-all personalized communication algorithm for a 2D torus inwormhole-routed networks. Our complete exchange algorithm adopts divide-and-conquer approach toreduce the number of start-up latency significantly, which is a good metric for network performancein wormhole networks. First, we divide the whole network into 2x2 basic cells, After speciallydesignated nodes called master nodes have collected messages to transmit to the rest of the basic cell,only master nodes perform complete exchange with reduced network size, N/2 x N/2. When finishedwith this complete exchange in master nodes, these nodes distribute messages to the rest of the masternode, which results in the desired complete exchange communication. After we present our algorithms,we analyze time complexities and compare our algorithms with several previous algorithms. And weshow that our algorithm is efficient by a factor of 2 in the required start-up time which means thatour algorithm is suitable for wormhole-routed networks.

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Six Color Separation for Reducing Graininess in a Middle Tone Region (중간 계조 영역에서 낟알 무늬 특성을 감소시키기 위한 6색 분리 방법)

  • 손창환;김윤태;조양호;하영호
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.6
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    • pp.51-59
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    • 2004
  • This paper proposes an improved six-color separation reducing the graininess in a middle tone region based on the standard deviation of the lightness and chrominance in S-CIELAB space. Graininess is regarded as visual perception for the fluctuation of the lightness of the light cyan and cyan or light magenta and magenta. In the conventional methods, the granularity is extremely heuristic and inaccurate due to the use of the visual examination score. Accordingly, this paper proposes a method to calculate the objective granularity for six color separation. First, we use the lightness, redness-greenness, and yellowness-blueness of the S-CIELAB space reflecting the spatial-color sensitivity of the human and normalize the sum of the three standard deviations. Finally, we apply the proposed granularity to the six color separation after assigning the granularity to the lookup table and obtain the result reducing the graininess in a middle tone region.

Motion Adaptive Temporal Noise Reduction Filtering Based on Iterative Least-Square Training (반복적 최적 자승 학습에 기반을 둔 움직임 적응적 시간영역 잡음 제거 필터링)

  • Kim, Sung-Deuk;Lim, Kyoung-Won
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.5
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    • pp.127-135
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    • 2010
  • In motion adaptive temporal noise reduction filtering used for reducing video noises, the strength of motion adaptive temporal filtering should be carefully controlled according to temporal movement. This paper presents a motion adaptive temporal filtering scheme based on least-square training. Each pixel is classified to a specific class code according to temporal movement, and then, an iterative least-square training method is applied for each class code to find optimal filtering coefficients. The iterative least-square training is an off-line procedure, and the trained filter coefficients are stored in a lookup table (LUT). In actual noise reduction filtering operation, after each pixel is classified by temporal movement, simple filtering operation is applied with the filter coefficients stored in the LUT according to the class code. Experiment results show that the proposed method efficiently reduces video noises without introducing blurring.

A Design of Adder and Multiplier on GF ( $2^m$ ) Using Current Mode CMOS Circuit with ROM Structure (ROM 構造를 갖는 電流방식 COMS 回路에 依한 GF ( $2^m$ ) 上의 演算器 설계)

  • Yoo, In-Kweon;Seong, Hyeon-Kyeong;Kang, Sung-Su;Kim, Heung-Soo
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.10
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    • pp.1216-1224
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    • 1988
  • In this paper, it is presented element generation, addition, multiplication and division algorithm over GF ($2^m$) to calculate multiple-valued logic function. The results of addition and multiplication among these algorithms are applied to the current mode CMOS circuits with ROM structure to design of adder and multiplier on GF ($2^m$). Table-lookup and Euclid's algorithm are required the computation in large quentities when multiple-valued logic functions are developed on GF ($2^m$). On the contrary the presented operation algorithms are prefered to the conventional methods since they are processed without relation to increasing degree m in the general purpose computer. Also, the presened logic circuits are suited for the circuit design of the symmetric multiplevalued truth-tables and they can be implemented addition and multiplication on GF ($2^m$) simultaueously.

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A Study of the Modulus Multiplier Design for Speed up Throughput in the Public-key Cryptosystem (공개키 암호시스템의 처리속도향상을 위한 모듈러 승산기 설계에 관한 연구)

  • 이선근;김환용
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.40 no.4
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    • pp.51-57
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    • 2003
  • The development of the communication network and the other network method can generate serious social problems. So, it is highly required to control security of network. These problems related security will be developed and keep up to confront with anti-security field such as hacking, cracking. The way to preserve security from hacker or cracker without developing new cryptographic algorithm is keeping the state of anti-cryptanalysis in a prescribed time by means of extending key-length. In this paper, we proposed M3 algorithm for the reduced processing time in the montgomery multiplication part. Proposed M3 algorithm using the matrix function M(.) and lookup table perform optionally montgomery multiplication with repeated operation. In this result, modified repeated operation part produce 30% processing rate than existed montgomery multiplicator. The proposed montgomery multiplication structured unit array method in carry generated part and variable length multiplication for eliminating bottle neck effect with the RSA cryptosystem. Therefore, this proposed montgomery multiplier enforce the real time processing and prevent outer cracking.

Development of a Temperature Control Model for a Hot Coil Strip using on-line Retrainable RBF Network (온라인 재학습 가능한 RBF 네트워크를 이용한 열연 권취 온도 제어 모델 개발)

  • Jeong, So-Young;Lee, Min-Ho;Lee, Soo-Young
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.8
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    • pp.39-47
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    • 1999
  • This paper describes on-line retrainable RBF network in order to control the coiling temperature for a hot coil strip at Pohang Iron & Steel Company(POSCO). The proposed neural network can be used for improving conventional rule-based lookup table, which generates a heat transmission coefficient. To cope with time-varying characteristics of hot coil process, additional synaptic weights for on-line retraining purposes are introduced to hidden-to-output weights of conventional RBF network. Those weights are locally adjusted to newly incoming test data while preserving old information trained with off-line past data. Hence the effect of catastrophic interference can be greatly alleviated with the proposed network. In addition, rejection scheme is introduced for reliability concerns. From the experimental results applied to the actual process, it is noticed that overall control performance represents about 2.2% increase compared to the conventional one.

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Multi-scale Texture Synthesis (다중 스케일 텍스처 합성)

  • Lee, Sung-Ho;Park, Han-Wook;Lee, Jung;Kim, Chang-Hun
    • Journal of the Korea Computer Graphics Society
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    • v.14 no.2
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    • pp.19-25
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    • 2008
  • We synthesize a texture with different structures at different scales. Our technique is based on deterministic parallel synthesis allowing real-time processing on a GPU. A new coordinate transformation operator is used to construct a synthesized coordinate map based on different exemplars at different scales. The runtime overhead is minimal because this operator can be precalculated as a small lookup table. Our technique is effective for upsampling texture-rich images, because the result preserves texture detail well. In addition, a user can design a texture by coloring a low-resolution control image. This design tool can also be used for the interactive synthesis of terrain in the style of a particular exemplar, using the familiar 'raise and lower' airbrush to specify elevation.

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A Design of Low-power/Small-area Arithmetic Units for Mobile 3D Graphic Accelerator (휴대형 3D 그래픽 가속기를 위한 저전력/저면적 산술 연산기 회로 설계)

  • Kim Chay-Hyeun;Shin Kyung-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.5
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    • pp.857-864
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    • 2006
  • This paper describes a design of low-power/small-area arithmetic circuits which are vector processing unit powering nit, divider unit and square-root unit for mobile 3D graphic accelerator. To achieve area-efficient and low-power implementation that is an essential consideration for mobile environment, the fixed-point f[mat of 16.16 is adopted instead of conventional floating-point format. The vector processing unit is designed using redundant binary(RB) arithmetic. As a result, it can operate 30% faster and obtained gate count reduction of 10%, compared to the conventional methods which consist of four multipliers and three adders. The powering nit, divider unit and square-root nit are based on logarithm number system. The binary-to-logarithm converter is designed using combinational logic based on six-region approximation method. So, the powering mit, divider unit and square-root unit reduce gate count when compared with lookup table implementation.

A new pyramid structure for progressive transmission of palletized color images (팔레트를 가지는 칼라 영상의 점진적 전송을 위한 새로운 피라미드 자료 구조)

  • Jo, Yeong-U;Kim, Yeong-Mo
    • The Transactions of the Korea Information Processing Society
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    • v.3 no.6
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    • pp.1624-1635
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    • 1996
  • Palletized color images are the dominant type of the image used on Internet and World-Wide Web. In spite of this, most image compression and progressive transmission algorithm have been designed for continuous-tone images. Pallettize images. Palletized images differ from continuous-tone images in such a aspect that values are lookup table indices a new pyramid structure for compression and progressive transmission of a palletized image. In the proposed pyramid structure, the color of a node at higher level is the one that occupies the most part in 4 sons and each node is represented by a type code and several color codes. Since the proposed method do not exploit spatial correlation in an image, it is ideally applied to lossless compression and progressive transmission of palletized images. We have confirmed this through the experimental results.

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