English  |  正體中文  |  简体中文  |  Post-Print筆數 : 27 |  全文笔数/总笔数 : 110941/141868 (78%)
造访人次 : 47506522      在线人数 : 949
RC Version 6.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
搜寻范围 查询小技巧：
  • 您可在西文检索词汇前后加上"双引号"，以获取较精准的检索结果
  • 若欲以作者姓名搜寻，建议至进阶搜寻限定作者字段，可获得较完整数据
    •  进阶搜寻


    请使用永久网址来引用或连结此文件: https://nccur.lib.nccu.edu.tw/handle/140.119/113742


    题名: 利用小波轉換及向量化編碼法之影像隱藏技術
    作者: 歐陽彥杰
    黃育銓
    关键词: Data Hiding Vector Quantization Discrete Wavelet Transform Least Significant Bit
    日期: 2005
    上传时间: 2017-10-17 17:06:40 (UTC+8)
    摘要: 本文主要探討三種大小相同之灰階影像，機密影像（Secret Image）、掩護影像（Cover-Image）、及偽裝影像（Stego-Image）。本文主要目的是希望能夠將一張機密影像隱藏至一張掩護影像後產生一張所謂偽裝影像，偽裝影像與掩護影像幾近相同，因此機密影像於網路上傳遞將不易被察覺甚至破壞。即使，一旦掩護影像被有心人士竄改、壓縮、或裁切破壞等，依據本文之技術仍可以取出機密影像。在我們所提出之資料隱藏（Data-hiding）技術裏，首先為了提高隱藏的資料量，機密影像會先經過PNN、LBG、及編碼簿（Codebook）排序等向量編碼（Vector Quantization）方法做資料壓縮。接者，為了增強抗壓縮之強韌性，掩護影像會先經過三階之離散小波轉換（Discrete Wavelet Transform）後，再將索引值隱藏在小波係數裏。最後，再經由反離散小波轉換（Inverse Discrete Wavelet Transform）後產生一張具有強韌性的偽裝影像。我們所重建的機密影像當JPEG壓縮品質在百分之十五以下的壓縮率，其影像品質完全不受影響，甚至在百分之五十的壓縮率，其影像仍可清晰辨識。
    This work primarily explores three grey-level images of the same size 256×256 pixels, the secret image, the cover-image, and the stego-image. We embed a secret image into a cover-image to constitute a so-called stego-image such that the stego-image is visually indistinguishable from the original cover-image. Hence, the interceptors will not notice the existence of secret data in the stego-image. Furthermore, through our proposed data hiding scheme, the secret image still can be extracted from the stego-image even when the stego-image was attached or modified by popular image processing techniques, such as cropping and image compression.
    In our proposed scheme, first, in order to increase the hiding capacity, the secret image was compressed by those techniques of vector quantization. To enhance the robust property JPEG against compression attack , the indices were embedded into the lower band through three-level discrete wavelet transform. Finally, a robust stego-image can be retrieved through the processing of inverse discrete wavelet transform. The experimental results. Show that the reconstructed secret image can keep its original quality against JPEG compression at the compression ratio of 11% and is still be recognizable at the compression ratio of 50%.
    全文: 01
    關聯: TANET 2005 台灣網際網路研討會論文集
    資訊安全技術
    数据类型: conference
    显示于类别:[TANET 台灣網際網路研討會] 會議論文

    文件中的档案:

    档案 描述 大小格式浏览次数
    358.pdf1377KbAdobe PDF2189检视/开启


    在政大典藏中所有的数据项都受到原著作权保护.


    社群 sharing

    著作權政策宣告 Copyright Announcement
    1.本網站之數位內容為國立政治大學所收錄之機構典藏，無償提供學術研究與公眾教育等公益性使用，惟仍請適度，合理使用本網站之內容，以尊重著作權人之權益。商業上之利用，則請先取得著作權人之授權。
    The digital content of this website is part of National Chengchi University Institutional Repository. It provides free access to academic research and public education for non-commercial use. Please utilize it in a proper and reasonable manner and respect the rights of copyright owners. For commercial use, please obtain authorization from the copyright owner in advance.

    2.本網站之製作，已盡力防止侵害著作權人之權益，如仍發現本網站之數位內容有侵害著作權人權益情事者，請權利人通知本網站維護人員(nccur@nccu.edu.tw)，維護人員將立即採取移除該數位著作等補救措施。
    NCCU Institutional Repository is made to protect the interests of copyright owners. If you believe that any material on the website infringes copyright, please contact our staff(nccur@nccu.edu.tw). We will remove the work from the repository and investigate your claim.
    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - 回馈