本論文提出一個基於布林函數且具還原順序性之(t, n)秘密影像分享技術。本論文使用布林函數進行互斥或運算產生中間影像，每組的中間影像彼此之間具有關聯性，因此還原的時須依照順序還原中間影像，才能還原秘密影像。先將秘密影像分割，將分割後的子影像使用重排函數產生亂數子影像，將亂數子影像做(t, n)秘密影像分享，當中每一組有n個分享影像，且還原回秘密影像時，需收集t個分享影像，其中分享影像包括指定的分享影像，且指定的分享影像經雜湊函數產生出的中間影像，與其餘分享影像進行互斥或運算產生各組的分享影像。在此技術中還原具有順序性，必需從第一組還原，如果還原缺少指定的分享影像或無順序性，則無法還原後面組數。

This paper proposes a Boolean-based (t, n) secret image sharing scheme with recovering on pre-defined sequence. The proposed scheme first generates intermediate images, in which each intermediate image is related to different owner. The recovering process should follow a pre-defined sequence to obtain the intermediate images sequentially.
The proposed scheme performs as the following steps. First, the secret image is segmented to intermediate images. These intermediate images are then permuted to random-like images. Each random-like intermediate image is then applied to conventional (t, n) secret image sharing approach and XOR processing for obtaining n shared images. Moreover, results of performing hash and generation from some shared images are applied the XOR calculation to the shared images, excepting the pre-defined owner. In the recovering process, the intermediate images should be recovered sequentially. Moreover, the pre-defined owner should be included in the intermediate image’s recovery. Experimental results show that the proposed scheme can efficiently preserving a multi-person image’s face privacy.

目錄
第一章 緒論	1
1.1 研究背景與動機	1
1.2 研究架構	2
第二章 文獻探討	3
2.1 Li等人的方法	3
2.2 Yang等人的方法	4
2.3 Chen的方法	4
2.4 Chen等人的方法	5
2.5 Li等人的方法(2018)	5
2.6 Wu等人的方法	6
2.7 Beugnon等人的方法	6
第三章 本論文提出方法	8
3.1 GF(28)在秘密分享中的運算	8
3.2 本論文目的	9
3.3 基於布林函數並具還原順序性之(t, n)秘密影像分享技術演算法	12
3.3.1基於布林函數具還原順序性之(t, n)秘密影像分享的分享演算法	12
3.3.2基於布林函數具還原順序性之(t, n)秘密影像分享的還原演算法	15
第四章 實驗結果及討論	17
4.1 實驗結果	17
4.2比較與討論	26
第五章 結論	29
參考文獻	30
附錄一 英文論文	33
圖目錄
圖 1為本研究分享流程圖	9
圖 2為三人分享示意圖	11
圖 3本論文基於布林函數並具還原順序性之(t, n)秘密影像分享示意圖	14
圖 4本論文基於布林函數並具還原順序性之(t, n)秘密影像還原示意圖	16
圖 5本論文方法在三人分割且經重排函數示意圖	19
圖 6本論文方法在三人秘密影像分享實驗圖	19
圖 7本論文方法的三人秘密影像分享影像	20
圖 8本論文方法在五人分割且經重排函數示意圖	23
圖 9本論文方法在五人秘密影像分享實驗圖	24
圖 10本論文方法的五人秘密影像分享影像	25
表目錄
表 1本論文方法和七個秘密影像分享[2, 3, 6, 10, 11, 27, 29]中的比較表	27
表 2本論文方法和四個秘密影像分享[3, 10, 11, 27]中的比較表	28

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