隨著網路通訊的持續成長，資訊安全已成為一項重要的課題，秘密影像分享技術就是一種能夠保護我們秘密影像的方法。這項技術也被稱為(k,n) 門檻方法，它將秘密影像切分成n張子影像，並交由n位參與者保管，當我們收集到任意k張以上的子影像時就能成功還原回秘密影像，但假如我們只收集到少於k張的子影像時，則無法獲得足夠的資訊來還原秘密影像。
在這篇論文中，我們實作了三種現有的秘密影像分享的方法以及我們所提出的方法，這方法的主要精神是基於中國餘式定理來還原。跟其他方法相比，它需要較少的參數，但是需要一個額外的影像來確保我們能夠無失真的還原回秘密影像，而假如我們缺少這張影像，我們仍然可以還原出一張與秘密影像非常相似的影像。

The information security is more and more important while the internet communication grows up, so the secret image sharing technique will be a useful method to protect our secret. This technique, also called (k,n) threshold scheme, distributes secret image to n shadow images which can be preserved by n participants, and we can reveal the secret image by any more than k of the shadow images. If we only collect fewer than k shadow images, we cannot get sufficient information to reveal the secret image.
In this thesis, we implement three existing secret sharing method and the proposed method. The main idea of the proposed method is based on Chinese Remainder Theorem. It needs fewer parameters than other methods but needs an additional image to ensure we can completely reveal the secret image. However, if we do not have this image, we still can reveal a very similar image.

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[web01] http://mathworld.wolfram.com/LagrangeInterpolatingPolynomial.html, last access on March 7, 2013.
[web02]
http://en.wikipedia.org/wiki/Secret_sharing, last access on March 7, 2013.