• Annual Conference of KIPS
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• 2003.11b
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• pp.987-990
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• 2003

인터넷 회선이 빨라짐에 따라 고속라우터에 대한 요구가 증가하고 있다. 본 논문에서는 고속 라우팅의 핵심인 포워딩 룩업의 고속화를 위하여 비트맵을 이용한 기존의 룩업 알고리즘의 문제점을 실행-구동 시뮬레이션을 통하여 정확히 진단한 후, 카운티드 테이블을 추가하고, 룩업과정에서 사용되는 트랜스퍼 테이블의 중복된 라우팅 정보를 제거함과 아울러 주소 검색범위를 다원화함으로써 성능을 획기적으로 향상시킨 알고리즘을 소개한다. 이 방법은 기존 알고리즘의 룩업시간을 최소 46%, 최대 18%로 단축시키며, 카운티드 테이블을 간단한 하드웨어로 구현한다면 보다 향상된 성능을 기대찬 수 있을 것이다.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.6
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• pp.111-120
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• 2005

A cost effective three-dimensional color gamut mapping architecture is described. The conventional three-dimensional reduced resolution look-up table is considered and the concept of three-dimensional reduced resolution difference look-up table is introduced for cost effective and real-time color gamut mapping. The overall architecture uses one-dimensional memory decomposition of three-dimensional gamut mapping look-up table, three-dimensional interpolation and simple addition operation for generating the final gamut mapped colors. The required computational cost is greatly reduced by look-up table resolution adjustment and further reduced by the gamut mapping rule modification. The proposed architecture greatly reduces the required memory size and hardware complexity compared to the conventional method and it is suitable for real-time applications. The proposed hardware is suitable for FPGA and ASIC implementation and could be applied to the real-time display quality enhancement purposes.

• Journal of IKEEE
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• v.5 no.1 s.8
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• pp.24-34
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• 2001

IP address lookup is a major bottleneck of IP packet processing in high speed router. Existing IP lookup methods are focused only on lookup throughput without considering lookup table update. So their slow update can lead to lookup blocking or wrong routing decision based on obsolete routes. Especially existing IP lookup methods based on CAM(content addressable memory) have slow update of O(n) cycles in spite of their high throughput and low area complexity In this paper we proposes a new IP address lookup method based on pipelined CAM architecture(PICAM) with fast update of O(1) cycle of lookup table and high throughput and low area complexity.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.2 s.314
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• pp.12-18
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• 2007

The three dimensional interpolation is widely used for many kinds of color signal transformation such as real-time color gamut mapping. Given input color signal, the output color signal is approximately calculated by the interpolation with the input point and extracted values from a lookup table which is constructed by storing the values of transformation at regularly packed sample points. Apparently, errors of the interpolated approximation heavily depend on the selection of the lookup table. In this paper, a least square method is applied to assigning values of the lookup table with fixed size in order to minimize error of three-dimensional interpolation. The experimental result shows that the proposed method has better interpolation performance.

• Proceedings of the KIEE Conference
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• 2005.07d
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• pp.2950-2952
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• 2005

색각 이상자는 특성 색상에 대한 판별이 떨어지므로 색 정보에 대한 판별 향상을 위해서는 색상의 적절한 변형이 필요하다. 본 논문은 전 세계의 1/12에 해당하는 색각 이상자를 위한 실시간 색역폭 사상 구현에 관한 것이다. 색각 이상자를 위한 실시간 색역폭 사상은 3차원 룩업 테이블과 이를 이용한 3차원 보간기로 구성이 되며, 여기서 3차원 룩업 테이블은 각각의 색각 이상자들의 특성을 고려한 보정 데이터를 사용한다. 제안된 방식은 DTV와 같이 고속의 영상 신호에 적용이 용이하고 또한 3차원 룩업 테이블의 변경에 따라 여러 유형의 색각 이상자에도 적용이 가능하다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.12C
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• pp.1068-1074
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• 2008

In this paper, we propose the algorithm for generating the array of elemental image by using look-up table (L UT) in a computer generated integral imaging system. It makes the LUT independently for the projection point of x and y. The algorithm using LUT to the existing ones needs less computing time to generate the array of elemental image. By comparing the computing time of proposed algorithm with that of the existing algorithms e xperimently, we proved the efficiency of proposed algorithm.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2018.06a
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• pp.182-184
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• 2018

본 논문에서는 HDR 영상 신호의 고속 광전변환을 위한 파라미터 룩업 테이블 기반 구간 선형 근사 방법을 제안한다. 제안하는 방법은 고속화하기 위한 광전변환함수의 입력 값의 범위를 다수개의 구간으로 나누고 각 구간마다 별도의 선형 근사함수를 구하여 광전변환함수를 근사하고 각 구간별로 필요한 선형 근사함수의 파라미터를 룩업 테이블에 미리 저장하고 사용함으로써 보다 빠른 근사 값 계산이 가능하다. 제안한 방법의 성능 평가를 위해 MPEG 에서 제공하는 참조 소프트웨어인 HDRTools 를 기반으로 실험을 수행했고 이를 통해 참조 소프트웨어에 구현되어 있는 기존의 고속화 방법과 비교하여 더 적은 연산 수를 가지며 평균 24% 빠른 처리속도와 약 0.05dB 의 평균 PSNR 손실을 보임을 확인하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.7B
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• pp.647-659
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• 2003

LPM(Longest Prefix Matching)searching in If address lookup is a major bottleneck of IP packet processing in the high speed router. In the conventional lookup table for the LPM searching in CAM(Content Addressable Memory) the complexity of fast update take 0(1). In this paper, we designed pipeline architecture for fast update of 0(1) cycle of lookup table and high throughput and low area complexity on LPM searching. Lookup-table architecture was designed by CAM(Content Addressable Memory)away that uses 1bit RAM(Random Access Memory)cell. It has three pipeline stages. Its LPM searching rate is affected by both the number of key field blocks in stage 1 and stage 2, and distribution of matching Point. The RTL(Register Transistor Level) design is carried out using Verilog-HDL. The functional verification is thoroughly done at the gate level using 0.35${\mu}{\textrm}{m}$ CMOS SEC standard cell library.

• Journal of KIISE
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• v.44 no.3
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• pp.253-260
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• 2017

In computer graphics, high-quality lens flares have been generated using costly offline rendering. A recent matrix-based approximation has enabled generation of high-quality lens flares suitable for real-time applications, but its quality degrades due to the lack of nonlinear patterns of lens flares. This paper introduces a method for high-quality lens-flare rendering, which includes blending of both nonlinear as well as linear patterns. The nonlinear patterns are pre-rendered or photo-graphically captured offline and stored in a look-up table. The online stage reads only the pattern by looking up the table using a light angle, hence making its performance drop negligible while greatly improving the quality.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.9
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• pp.724-733
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• 2003

Generally, dividers have been designed to use iteration, but recently the research on the pipelined divider is underway. It is a difficult point in the known pipelined division unit that a large lookup table is required. In this paper, the cost-effective pipelined divider is proposed, that needs a lookup table smaller than that of the other pipelined divider. The latency of the proposed divider is 3 cycles. We obtain a 30% reduced area than that of P. Hung.