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Hoi-kwong Lo - One of the best experts on this subject based on the ideXlab platform.

  • A quantum analog of Huffman Coding
    IEEE Transactions on Information Theory, 2000
    Co-Authors: Samuel L. Braunstein, Daniel Gottesman, Christopher A Fuchs, Hoi-kwong Lo
    Abstract:

    We analyze a generalization of Huffman Coding to the quantum case. In particular, we notice various difficulties in using instantaneous codes for quantum communication. Nevertheless, for the storage of quantum information, we have succeeded in constructing a Huffman Coding inspired quantum scheme. The number of computational steps in the enCoding and deCoding processes of N quantum signals can be made to be of polylogarithmic depth by a massively parallel implementation of a quantum gate array. This is to be compared with the O(N/sup 3/) computational steps required in the sequential implementation by Cleve and DiVincenzo (see Phys. Rev., vol.A54, p.2636, 1996) of the well-known quantum noiseless block-Coding scheme of Schumacher. We also show that O(N/sup 2/(log N)/sup a/) sequential computational steps are needed for the communication of quantum information using another Huffman Coding inspired scheme where the sender must disentangle her enCoding device before the receiver can perform any measurements on his signals.

  • A quantum analog of Huffman Coding
    arXiv: Quantum Physics, 1998
    Co-Authors: Samuel L. Braunstein, Daniel Gottesman, Christopher A Fuchs, Hoi-kwong Lo
    Abstract:

    We analyze a generalization of Huffman Coding to the quantum case. In particular, we notice various difficulties in using instantaneous codes for quantum communication. Nevertheless, for the storage of quantum information, we have succeeded in constructing a Huffman-Coding inspired quantum scheme. The number of computational steps in the enCoding and deCoding processes of N quantum signals can be made to be of polylogarithmic depth by a massively parallel implementation of a quantum gate array. This is to be compared with the O (N^3) computational steps required in the sequential implementation by Cleve and DiVincenzo of the well-known quantum noiseless block Coding scheme of Schumacher. We also show that O(N^2(log N)^a) computational steps are needed for the communication of quantum information using another Huffman-Coding inspired scheme where the sender must disentangle her enCoding device before the receiver can perform any measurements on his signals.

KASEI ARIMOTO - One of the best experts on this subject based on the ideXlab platform.

  • CAM-based VLSI architecture for Huffman Coding with real-time optimization of the code word table [image Coding example]
    2005 IEEE International Symposium on Circuits and Systems, 2005
    Co-Authors: Takeshi Kumaki, K. Dosaka, H Noda, T. Koide, Hans Jurgen Mattausch, Y. Kuroda, KASEI ARIMOTO
    Abstract:

    Huffman Coding is probably the best known and most widely used data compression technique. Nevertheless, the task of further decreased compression ratio through Huffman code up-dating in real-time is still a largely unsolved problem. In this paper, a novel architecture for CAM (content addressable memory)-based Huffman Coding with real-time optimization of the code word table, called CHRC, is proposed. A CAM is exploited to implement fast Huffman enCoding, and simultaneously the code word table is reconstructed and up-dated in realtime. The effectiveness of the proposed architecture is verified by structure, enCoding flow and simulation results. The example of a JPEG application shows that our proposed CHRC method is able to achieve up to 40% smaller encoded picture sizes, and 6 times smaller clock cycle number for the enCoding hardware than conventional Huffman Coding methods.

Takeshi Kumaki - One of the best experts on this subject based on the ideXlab platform.

  • CAM-based VLSI architecture for Huffman Coding with real-time optimization of the code word table [image Coding example]
    2005 IEEE International Symposium on Circuits and Systems, 2005
    Co-Authors: Takeshi Kumaki, K. Dosaka, H Noda, T. Koide, Hans Jurgen Mattausch, Y. Kuroda, KASEI ARIMOTO
    Abstract:

    Huffman Coding is probably the best known and most widely used data compression technique. Nevertheless, the task of further decreased compression ratio through Huffman code up-dating in real-time is still a largely unsolved problem. In this paper, a novel architecture for CAM (content addressable memory)-based Huffman Coding with real-time optimization of the code word table, called CHRC, is proposed. A CAM is exploited to implement fast Huffman enCoding, and simultaneously the code word table is reconstructed and up-dated in realtime. The effectiveness of the proposed architecture is verified by structure, enCoding flow and simulation results. The example of a JPEG application shows that our proposed CHRC method is able to achieve up to 40% smaller encoded picture sizes, and 6 times smaller clock cycle number for the enCoding hardware than conventional Huffman Coding methods.

  • multi port cam based vlsi architecture for Huffman Coding with real time optimized code word table
    Midwest Symposium on Circuits and Systems, 2005
    Co-Authors: Takeshi Kumaki, K. Dosaka, H Noda, T. Koide, Y. Kuroda, Jurgen H Mattausch, Kazutami Arimoto, Kazunori Saito
    Abstract:

    This paper presents a multi-port CAM based VLSI architecture for Huffman Coding with real-time optimized code word table as a novel architecture for high-speed parallel Huffman Coding. The multi-port CAM technology exploited is the FMCAM (flexible multi-port content addressable memory) architecture (Kumaki et al., 2004), which enables fast parallel Huffman enCoding. At the same time, the code word table is reconstructed according to the frequency of received input symbols and is up-dated in real-time. Since two the functions work in parallel, the proposed architecture realizes fast parallel enCoding and keeps a constantly high compression ratio. The simulation results for the JPEG application show that the proposed architecture can achieve up to 20% smaller encoded picture sizes, and four times reduced clock cycle numbers for the enCoding hardware (8 port case) in comparison to conventional fast Huffman Coding architectures.

Samuel L. Braunstein - One of the best experts on this subject based on the ideXlab platform.

  • A quantum analog of Huffman Coding
    IEEE Transactions on Information Theory, 2000
    Co-Authors: Samuel L. Braunstein, Daniel Gottesman, Christopher A Fuchs, Hoi-kwong Lo
    Abstract:

    We analyze a generalization of Huffman Coding to the quantum case. In particular, we notice various difficulties in using instantaneous codes for quantum communication. Nevertheless, for the storage of quantum information, we have succeeded in constructing a Huffman Coding inspired quantum scheme. The number of computational steps in the enCoding and deCoding processes of N quantum signals can be made to be of polylogarithmic depth by a massively parallel implementation of a quantum gate array. This is to be compared with the O(N/sup 3/) computational steps required in the sequential implementation by Cleve and DiVincenzo (see Phys. Rev., vol.A54, p.2636, 1996) of the well-known quantum noiseless block-Coding scheme of Schumacher. We also show that O(N/sup 2/(log N)/sup a/) sequential computational steps are needed for the communication of quantum information using another Huffman Coding inspired scheme where the sender must disentangle her enCoding device before the receiver can perform any measurements on his signals.

  • A quantum analog of Huffman Coding
    arXiv: Quantum Physics, 1998
    Co-Authors: Samuel L. Braunstein, Daniel Gottesman, Christopher A Fuchs, Hoi-kwong Lo
    Abstract:

    We analyze a generalization of Huffman Coding to the quantum case. In particular, we notice various difficulties in using instantaneous codes for quantum communication. Nevertheless, for the storage of quantum information, we have succeeded in constructing a Huffman-Coding inspired quantum scheme. The number of computational steps in the enCoding and deCoding processes of N quantum signals can be made to be of polylogarithmic depth by a massively parallel implementation of a quantum gate array. This is to be compared with the O (N^3) computational steps required in the sequential implementation by Cleve and DiVincenzo of the well-known quantum noiseless block Coding scheme of Schumacher. We also show that O(N^2(log N)^a) computational steps are needed for the communication of quantum information using another Huffman-Coding inspired scheme where the sender must disentangle her enCoding device before the receiver can perform any measurements on his signals.

Xinpeng Zhang - One of the best experts on this subject based on the ideXlab platform.

  • reversible data hiding in encrypted images based on multi msb prediction and Huffman Coding
    IEEE Transactions on Multimedia, 2020
    Co-Authors: Youzhi Xiang, Xinpeng Zhang
    Abstract:

    With the development of cloud storage and privacy protection, reversible data hiding in encrypted images (RDHEI) has attracted increasing attention as a technology that can: embed additional data in the image encryption domain, ensure that the embedded data can be extracted error-free, and the original image can be restored losslessly. In this paper, a high-capacity RDHEI algorithm based on multi-MSB (most significant bit) prediction and Huffman Coding is proposed. At first, multi-MSB of each pixel was predicted adaptively and marked by Huffman Coding in the original image. Then, the image was encrypted by a stream cipher method. At last, the vacated space can be used to embed additional data by multi-MSB substitution. Experimental results show that our method achieved higher embedding capacity while comparing with the state-of-the-art methods.

  • reversible data hiding in encrypted images based on multi msb prediction and Huffman Coding
    IEEE Transactions on Multimedia, 2020
    Co-Authors: Zhaoxia Yin, Youzhi Xiang, Xinpeng Zhang
    Abstract:

    With the development of cloud storage and privacy protection, reversible data hiding in encrypted images (RDHEI) has attracted increasing attention as a technology that can: embed additional data in the image encryption domain, ensure that the embedded data can be extracted error-free, and the original image can be restored losslessly. In this paper, a high-capacity RDHEI algorithm based on multi-MSB (most significant bit) prediction and Huffman Coding is proposed. At first, multi-MSB of each pixel was predicted adaptively and marked by Huffman Coding in the original image. Then, the image was encrypted by a stream cipher method. At last, the vacated space can be used to embed additional data by multi-MSB substitution. Experimental results show that our method achieved higher embedding capacity while comparing with the state-of-the-art methods.