論文中文摘要

資訊隱藏或資訊嵌入的技術，是使我們能夠秘密的嵌入某些重要資訊到數位媒體檔案上的技術，這些數位媒體檔案包括了影像檔、電影檔、以及聲音檔。近年來，資料隱藏的實際應用與需求越來越廣泛，例如可以應用在著作權保護、秘密通訊、資料註解、真實性與完整性的驗證上。端看我們的應用與需求，若應用在著作權保護方面的話，則我們強調於資訊隱藏的強韌性，通稱做數位浮水印。若應用在秘密通訊上的話，就稱做隱像學，著重的則是我們隱藏的資訊與我們能夠秘密嵌入的資料量有多少。

初期對於數位視訊檔案所發展的資訊影藏技術，多半是從針對影像檔案的技術加強衍生而來的，但是對於現今許多視訊壓縮的方法並不適合。近年來有部分文獻提出對於數位視訊壓縮格式專屬的資訊隱藏方法，但是詳細探究這些方法的運作原理，絕大部分只能對於獨立框頁(INTRA-frame)做資訊隱藏，如此一來便限制了其應用範圍，例如說無法對於交互引用框頁(INTER-frame)做資訊隱藏，便無法保障全部檔案內容的真實性與完整性的驗證，並且其能夠秘密嵌入的資料量也倍受限制，因此這個問題是值得去探討以及進一步去加以研究的。

在本篇論文中我們發展出一套有效的數位影片資訊隱藏技術，提出的方法是在交互引用框頁(INTER-frame)做資訊隱藏，此方法可以在壓縮或是未壓縮的數位影片的中藏入資訊；並且可以針對我們資訊隱藏所需求的應用來決定如何調整數位視訊的品質與藏入資訊量的比重。此外所藏入的資訊可以直接的被抽取出來，而不需要用到原始的視訊。詳細的實驗結果證明了我們所提出的方法是可行的，並且相較於所參考的文獻，我們提出的方法有更好的表現。

Abstract

There are many of research have been proposed for embedding information into digital video. However, most of those schemes extending information hiding technique for still image to video by treating each single frame as a still image and embed data in intra-frame.

In this paper, we propose an effective information-hiding scheme for digital video. This scheme embeds information in digital video using the phase angle of the motion vector of the macroblock in the inter-frame. We can apply this scheme to either compressed or uncompressed videos. Furthermore, the embedded information can extracted directly without using the original video sequences. Our experimental results prove the feasibility of the proposed methods. Comparing with the other literature, our method has better performance.

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