• 제목/요약/키워드: Gray coding

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A Study on the Block Truncation Coding Using the Bit-plane Reduction (비트평면 감축을 이용한 블록 절단부호화에 관한 연구)

  • 이형호;박래홍
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.24 no.5
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    • pp.833-840
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    • 1987
  • A new Block Truncation Coding(BTC) technique reducing the bit-plane and using differential pulse code modulation (DPCM) is proposed and compared with the conventional BTC methods. A new technique decides whether the subblock can be approximated to be uniform or not. If the subblock can be approximated to be uniform(merge mode), we transmit only the gray-level informantion. It not (split mode), we transmity both the bit-plane and the gray-level information. DPCM method is proposed to the encoding of gray-level information when the subblock can be approximated to be uniform. Also modified quantization method is presented to the encoding of gray-level information when the subblock is not uniform. This technique shows the results of coding 256 level images at the average data rate of about 0.75 bits/pel.

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A Ranking Method for Improving Performance of Entropy Coding in Gray-Level Images (그레이레벨 이미지에서의 엔트로피 코딩 성능 향상을 위한 순위 기법)

  • You, Kang-Soo;Sim, Chun-Bo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.4
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    • pp.707-715
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    • 2008
  • This paper proposes an algorithm for efficient compression gray-level images by entropy encoder. The issue of the proposed method is to replace original data of gray-level images with particular ranked data. For this, first, before encoding a stream of gray-level values in an image, the proposed method counts co-occurrence frequencies for neighboring pixel values. Then, it replaces each pay value with particularly ranked numbers based on the investigated co-occurrence frequencies. Finally, the ranked numbers are transmitted to an entropy encoder. The proposed method improves the performance of existing entropy coding by transforming original gray-level values into rank based images using statistical co-occurrence frequencies of gray-level images. The simulation results, using gray-level images with 8-bits, show that the proposed method can reduce bit rate by up to 37.85% compared to existing conventional entropy coders.

Coded Single Input Channel for Color Pattern Recognition in Joint Transform Correlator

  • Jeong, Man-Ho
    • Journal of the Optical Society of Korea
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    • v.15 no.4
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    • pp.335-339
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    • 2011
  • Recently, we reported a single input channel joint transform correlator for the color pattern recognition which decomposes the input color image into three R, G, and B gray components and adds those components into a single gray image in the input plane. This technique has the merit of a single input channel instead of three input channels. However, we found this technique has some problems with discrimination impossibility in the case of a simple primary color pattern which results in the same gray level through the addition process. Thus, we propose a modified coding technique which selectively recombines the decomposed three R, G, and B gray components instead of the simple adding process. Simulated results show that the modified coding technique can accurately discriminate a variety of kinds of color images.

Differential Spatial Modulation with Gray Coded Antenna (그레이 코드화된 안테나 순서의 차등 공간 변조)

  • Kim, Jeong-Su;Lee, Moon Ho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.5
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    • pp.51-59
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    • 2017
  • In this paper, we propose a gray code order of antenna index permutations for differential spatial modulation (DSM). To facilitate the implementation, the well-known Trotter-Johnson ranking and unranking algorithms are adopted, which result in similar computational complexity to the existing DSM that uses the lexicographic order. The signal-to-noise ratio gain achieved by the proposed gray code order over the lexicographic order is also analyzed and verified via simulations. Based on the gray coding framework, we further propose a diversity-enhancing scheme named intersected gray (I-gray) code order, where the permutations of active antenna indices are selected directly from the odd (or even) positions of the full permutations in the gray code order. From analysis and simulations, it is shown that the I-gray code order can harvest an additional transmit diversity order with respect to the gray code order.

An Implementation of efficient Image Compression JPEG2000 Based on DSPs (DSP를 이용한 JPEG2000 의 고효율 이미지 압축 구현)

  • 김흥선;조준기;황민철;남주훈;고성제
    • Proceedings of the IEEK Conference
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    • 2003.07e
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    • pp.2363-2366
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    • 2003
  • With the increasing use of multimedia technologies, image compression requires higher performance as well as new features such as embedded Tossy to lossless coding, various progressive order, error resilience and region-of-interest coding. In the specific area of still image encoding, a new standard, the JPEG2000, has been currently developed. This paper presents a new compression scheme based on JPEG2000. In the proposed scheme, gray coding is applied to the wavelet coefficient. Since gray coding produces an image whose bit plane is will clustered. The proposed method improves compression efficiency of the JPEG2000.

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Bitwise Decomposition Algorithm for Gray Coded M-PSK Signals (Gray 부호화된 M-PSK 신호의 비트 정보 분할 알고리듬)

  • Kim Ki-Seol;Hyun Kwang-Min;Park Sang-Kyu
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.8A
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    • pp.784-789
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    • 2006
  • In this paper, we propose a bitwise information decomposition algorithm for an M-PSK signal based on the Max-Log-MAP algorithm. In order to obtain the algorithm, we use a coordinate transformation from M-PSK to M-PAM signal space. Using the proposed algorithm, we analyze the performance of a Turbo iterative decoding method. The proposed algorithm can be applicable not only for a communication with PSK and iterative decoding method but for adaptive modulation and coding system.

A Robust Sequential Preprocessing Scheme for Efficient Lossless Image Compression (영상의 효율적인 무손실 압축을 위한 강인한 순차적 전처리 기법)

  • Kim, Nam-Yee;You, Kang-Soo;Kwak, Hoon-Sung
    • Journal of Internet Computing and Services
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    • v.10 no.1
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    • pp.75-82
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    • 2009
  • In this paper, we propose a robust preprocessing scheme for entropy coding in gray-level image. The issue of this paper is to reduce additional information needed when bit stream is transmitted. The proposed scheme uses the preprocessing method of co-occurrence count about gray-levels in neighboring pixels. That is, gray-levels are substituted by their ranked numbers without additional information. From the results of computer simulation, it is verified that the proposed scheme could be reduced the compression bit rate by up to 44.1%, 37.5% comparing to the entropy coding and conventional preprocessing scheme respectively. So our scheme can be successfully applied to the application areas that require of losslessness and data compaction.

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Identification of Botrytis cinerea, the Cause of Post-Harvest Gray Mold on Broccoli in Korea

  • Aktaruzzaman, Md.;Afroz, Tania;Hong, Sae-Jin;Kim, Byung-Sup
    • Research in Plant Disease
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    • v.23 no.4
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    • pp.372-378
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    • 2017
  • In this study, we identified the causative agent of post-harvest gray mold on broccoli that was stored on a farmers' cooperative in Pyeongchang, Gangwon Province, South Korea, in September 2016. The incidence of gray mold on broccoli was 10-30% after 3-5 weeks of storage at $3^{\circ}C$. Symptoms included brownish curd and gray-to-dark mycelia with abundant conidia on the infected broccoli curds. The fungus was isolated from infected fruit and cultured on potato dextrose agar. To identify the fungus, we examined the morphological characteristics and sequenced the rDNA of the fungus and confirmed its pathogenicity according to Koch's postulates. The results of the morphological examination, pathogenicity test, and sequencing of the 5.8S rDNA of the internal transcribed spacer regions (ITS1 and ITS4) and three nuclear protein-coding genes, G3PDH, HSP60, and RPB2, revealed that the causal agent of the post-harvest gray mold on broccoli was Botrytis cinerea. To our knowledge, this is the first report of post-harvest gray mold on broccoli in Korea.

A Study on LIFS Image Coding via Gram-Schmidt Orthogonalization - Fast Coding Algorithm - (Gram-Schmidt 직교화를 이용한 LIFS 영상 부호화법에 관한 연구 -부호화 고속 알고리즘-)

  • 유현배
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.4 no.2
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    • pp.96-101
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    • 2003
  • Recently, Fractal Image Coding has been studied as a way of efficient data compressing scheme. In the beginning, Fractal Image Coding has been studied for the data compressing in black & white images and linear images. A. E. Jacquin suggested LIFS which expends to Fractal Image Coding for a gray scale image. Currently, YTKT's LIFS scheme which is using Gram-Schmidt is so efficient that enough to compete with the JPEG which is the national standards. This paper investigates the way of greatly reduced calculation for the orthogonalization algorithm.

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First Report of Gray Mold Disease of Sweet Basil (Ocimum basilicum) Caused by Botrytis cinerea in Korea

  • Aktaruzzaman, Md.;Kim, Joon-Young;Afroz, Tania;Hong, Sae-Jin;Kim, Byung-Sup
    • The Korean Journal of Mycology
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    • v.43 no.4
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    • pp.277-280
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    • 2015
  • In August 2015, we collected samples of gray mold from sweet basil growing in Sachunmeon, Gangneung, Gangwon Province, Korea. Symptoms included extensive growth of mycelia with gray conidia on young leaves, stems, and blossoms. The pathogen was isolated from infected leaves and blossoms and the fungus was cultured on potato dextrose agar. For identification of the fungus, morphology and rDNA sequencing analysis of the fungus were performed, which confirmed its pathogenicity according to Koch's postulates. The results of morphological examinations, pathogenicity tests, and the rDNA sequences of the internal transcribed spacer regions (ITS1 and ITS4) and the three nuclear protein-coding genes G3PDH, HSP60, and RPB2 showed that the causal agent was Botrytis cinerea. This is the first report of gray mold caused by Botrytis cinerea on sweet basil in Korea.