• Title/Summary/Keyword: lossless compression

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Lossless Compression Algorithm using Spatial and Temporal Information (시간과 공간정보를 이용한 무손실 압축 알고리즘)

  • Kim, Young Ro;Chung, Ji Yung
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.5 no.3
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    • pp.141-145
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    • 2009
  • In this paper, we propose an efficient lossless compression algorithm using spatial and temporal information. The proposed method obtains higher lossless compression of images than other lossless compression techniques. It is divided into two parts, a motion adaptation based predictor part and a residual error coding part. The proposed nonlinear predictor can reduce prediction error by learning from its past prediction errors. The predictor decides the proper selection of the spatial and temporal prediction values according to each past prediction error. The reduced error is coded by existing context coding method. Experimental results show that the proposed algorithm has better performance than those of existing context modeling methods.

Modification of the integer transform in H.264/AVC for lossless compression (무손실 압축을 위한 H.264/AVC 정수 변환의 변형)

  • Yoo, Hoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.10
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    • pp.2254-2260
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    • 2010
  • This papers describes modification of the integer transform used in H.264/AVC in order to efficiently apply to lossless compression. The previous reversible integer transform is not efficient for lossless compression due to large dynamic range of the transform coefficients. To reduce the problem, efficient and reversible integer transforms are proposed. The modified transforms are designed based on the lifting scheme for fast transforms. This paper introduces signal flow graphs for the proposed fast transforms and provides corresponding experimental results. The results indicate that the proposed modified reversible integer transform are superior to the previous transform in terms of lossless compression efficiency.

A Preprocessing Algorithm for Efficient Lossless Compression of Gray Scale Images

  • Kim, Sun-Ja;Hwang, Doh-Yeun;Yoo, Gi-Hyoung;You, Kang-Soo;Kwak, Hoon-Sung
    • 제어로봇시스템학회:학술대회논문집
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    • pp.2485-2489
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    • 2005
  • This paper introduces a new preprocessing scheme to replace original data of gray scale images with particular ordered data so that performance of lossless compression can be improved more efficiently. As a kind of preprocessing technique to maximize performance of entropy encoder, the proposed method converts the input image data into more compressible form. Before encoding a stream of the input image, the proposed preprocessor counts co-occurrence frequencies for neighboring pixel pairs. Then, it replaces each pair of adjacent gray values with particular ordered numbers based on the investigated co-occurrence frequencies. When compressing ordered image using entropy encoder, we can expect to raise compression rate more highly because of enhanced statistical feature of the input image. In this paper, we show that lossless compression rate increased by up to 37.85% when comparing results from compressing preprocessed and non-preprocessed image data using entropy encoder such as Huffman, Arithmetic encoder.

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Depending on PACS Operating System Differences Analysis of Usefulness of Lossless Compression Method in Medical Image Upload: SNR, CNR, Histogram Comparative Analysis (PACS운영 시스템 차이에 따른 의료 영상 업로드 시 무손실 압축 방식의 유용성 분석: SNR, CNR, Histogram 비교 분석을 중심으로)

  • Choi, Ji-An;Hwang, Jun-Ho;Lee, Kyung-Bae
    • The Journal of the Korea Contents Association
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    • v.18 no.3
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    • pp.299-308
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    • 2018
  • This study focused on the fact that medical images that are issued at different hospitals may affect image quality on PACS when different software is used. A university hospital image was copied to the DICOM file and registered on the PACS of the university hospital B. The capacity and image quality of the software used in the university hospital were evaluated by SNR, CNR and histogram. As the compression ratio increased, SNR and CNR tended to decrease. Note that Lossless Compression decreased the data size by half compared to No Compression, but SNR and CNR did not change. As a result of the histogram analysis, the information loss due to the underflow phenomenon was conspicuous. When moving to another hospital, No compression or lossless compression method should be used. In conclusion, it is useful to use the lossless compression method, considering waiting time and economic efficiency in uploading.

Predictor Switching Algorithm for Lossless Compression (무손실 압축을 위한 예측기 스위칭 알고리즘)

  • Kim, Young-Ro;Yi, Joon-Hwan
    • 전자공학회논문지 IE
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    • v.47 no.2
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    • pp.27-31
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    • 2010
  • In this paper, a predictor switching algorithm for lossless compression is proposed. It uses adaptively one of two predictors using errors obtained by MED(median edge detector) and GAP(gradient adaptive prediction). The reduced error is measured by existing entropy method. Experimental results show that the proposed algorithm can compress higher than existing predictive methods.

Efficient rate control algorithm for video near-lossless compression (비디오 준무손실 압축을 위한 효율적인 레이트 컨트롤 알고리즘)

  • Joh, Beom Seok;Kim, Young Ro
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.6 no.2
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    • pp.11-17
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    • 2010
  • In this paper, we propose efficient rate control algorithm for video near-lossless compression. The proposed method adjusts pixel error range using amounts of previous encoded bits and target bits at a slice encoding interval. Thus, encoded bits by the proposed method are transmitted well through limited bandwidth without overflow. Also, target bits and encoded bits can be controlled according to transmission policy. Experimental results show that our proposed method not only almost fits compression ratio, but also has better image quality.

Near Lossless Compression of Medical luges with Vector Quantizer (Vector quantizer를 이용한 near lossless 의학 영상 압축)

  • Song, Y.C.;Ahn, C.B.
    • Proceedings of the KIEE Conference
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    • pp.1362-1364
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    • 1996
  • In this paper a Dear lossless compression of medical images with vector quantizer is proposed. In order to apply the vector quantizer to medical images, the peak error in the reconstructed image is reduced down to 1. Simulation results show that the proposed coding scheme provides better performance with a PSNR improvement compared to the conventional JPEG standard.

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Improving the Lifetime of NAND Flash-based Storages by Min-hash Assisted Delta Compression Engine (MADE (Minhash-Assisted Delta Compression Engine) : 델타 압축 기반의 낸드 플래시 저장장치 내구성 향상 기법)

  • Kwon, Hyoukjun;Kim, Dohyun;Park, Jisung;Kim, Jihong
    • Journal of KIISE
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    • v.42 no.9
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    • pp.1078-1089
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    • 2015
  • In this paper, we propose the Min-hash Assisted Delta-compression Engine(MADE) to improve the lifetime of NAND flash-based storages at the device level. MADE effectively reduces the write traffic to NAND flash through the use of a novel delta compression scheme. The delta compression performance was optimized by introducing min-hash based LSH(Locality Sensitive Hash) and efficiently combining it with our delta compression method. We also developed a delta encoding technique that has functionality equivalent to deduplication and lossless compression. The results of our experiment show that MADE reduces the amount of data written on NAND flash by up to 90%, which is better than a simple combination of deduplication and lossless compression schemes by 12% on average.

Forward Adaptive Prediction on Modified Integer Transform Coefficients for Lossless Image Compression (무손실 영상 압축을 위한 변형된 정수 변환 계수에 대한 순방향 적응 예측 기법)

  • Kim, Hui-Gyeong;Yoo, Hoon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.7
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    • pp.1003-1008
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    • 2013
  • This paper proposes a compression scheme based on the modified reversible integer transform (MRIT) and forward adaptive prediction for lossless image compression. JPEG XR is the newest image coding standard with high compression ratio and that composed of the Photo Core Transform (PCT) and backward adaptive prediction. To improve the efficiency and quality of compression, we substitutes the PCT and backward adaptive prediction for the modified reversible integer transform (MRIT) and forward adaptive prediction, respectively. Experimental results indicate that the proposed method are superior to the previous method of JPEG XR in terms of lossless compression efficiency and computational complexity.