在彩色視覺密碼技術中產生具有意義的彩色視覺分享

Generating Friendly and Colorful Shares in Color Visual Cryptography

10.29614/DRMM.201104.0004

陳宗和；曹凱翔；張述傑

影像加密 ； 視覺密碼學 ； 有意義的分享影像 ； image encryption ； visual cryptography ； meaningful

資訊安全通訊

17卷2期（2011 / 04 / 01）

37 - 47

繁體中文

對於影像及視訊等多媒體資訊的保護，在近年來已經成為十分重要的議題，許多對於影像加密的研究文獻中是以視覺密碼學(Visual Cryptography, VC)作為研究及改良的基礎，VC 技術將一張秘密影像分解成兩張看似無意義的分享影像(share image)，由單張的分享影像並不能得知任何跟原始秘密有關的資訊；若是蒐集到全部的分享影像並相疊之後，傴靠視覺即可得知原秘密，完全不必借助電腦設備。典型的視覺密碼學只能加密黑白影像，並且會產生出兩張無意義的分享影像(share)以解密，然而這些看似雜訊的分享影像，使用者在使用或管理上並不方便。本篇論文將改良傳統視覺密碼學，能夠加密彩色影像，所產生的彩色分享影像也將是有意義的彩色影像，因此，能方便使用者使用或管理大量的分享影像。此外，值得注意的，本方法並沒有產生額外的像素擴展。

Recently, multimedia security has drawn much attention in academia and industry. A lot of research aiming at the confidentiality of images has been proposed based on Visual Cryptography (VC) which encrypts a binary image by generating two meaningless share images. Subsequently, in case of stacking two collected share images, the original secret can be disclosed by human visual system without involving any computational resource. Unfortunately, it is inconvenient for users to manage more and more meaningless share images. In this paper, an enhanced scheme which encrypts a color secret image into two colorful and meaningful share images is proposed to facilitate the management and usage of numerous share images.

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