音訊秘密分享以數學計算的方式進行機密音訊的分享與還原，故而能提供良好的還原品質，甚至以無失真還原的方式出現。音訊秘密分享技術具有(t,n)門檻值(t<=n 且 2<=n)的特性。分享時將機密音訊分享成n把金鑰及與金鑰相對應的分享音訊，n為分享者的數目，且每位分享者僅握有一把金鑰及一份分享音訊，還原時只要取得t把金鑰及與金鑰相對應的分享音訊，經過還原計算後，即可獲得原機密音訊。如此，我們便無須擔心部份金鑰及分享音訊遺失會造成機密音訊無法復原，或是因複製多份機密音訊而降低安全性的問題。本論文採用極具效益的中國餘式定理為分享技術，在Android平台實際開發以達到高效率的音訊秘密分享系統。

This study presents an (s, t, n) progressive method for sharing an audio. In an (s, t, n) progressive audio sharing scheme, n shared audios are generated from the secret audio, gathering s shared audios acquires coarse resolution of secret audio, and using t shared audios can reconstruct the original secret audio losslessly. The Chinese Remainder Theorem is adopted in the proposed scheme to share coefficients acquired from 1-D integer wavelet transform with different thresholds. First, the maximum wavelet level number needed in 1-D integer wavelet transform is determined from thresholds s and t. Then, the proposed scheme applies the secret audio to 1-D integer wavelet transform for acquiring coefficients under different levels. At last, all wavelet coefficients are partitioned to (t-s+1) groups and share each group with different thresholds under inverse wavelet transform. Experimental results demonstrate that the proposed scheme can share secret audios efficiently and progressively.

目錄
第一章	緒論	1
1.1	研究背景與動機	1
1.2	研究目的與方法	2
1.3	論文架構	3
第二章	相關文獻探討	4
2.1	整數小波轉換技術	4
2.1.1	整數小波轉換公式	5
2.1.2	整數小波轉換音訊分解	5
2.2	中國餘式定理(t,n)分享技術	6
2.2.1	分享階段	6
2.2.2	還原階段	7
2.3	PCM音訊介紹	8
第三章	具音訊秘密分享功能之Android分享技術	9
3.1	(s,t,n)漸進式音訊秘密分享演算法	10
3.2	(s,t,n)漸進式音訊秘密還原演算法	11
3.3	子音訊分區策略	12
第四章	實驗結果與分析比較	14
4.1	實驗結果	15
4.2	分析比較	17
第五章	結論	21
參考文獻	22
附錄-英文論文	24

圖目錄
圖1、一維整數小波轉換圖	4
圖2、單聲道和雙聲道PCM音訊格式	8
圖3、二階小波轉換示意圖	12
圖4、機密音訊作門檻值(2,3,4)秘密分享和還原波形圖	15
圖5、機密音訊作門檻值(3,6,8)秘密分享和還原波形圖	17
圖6、門檻值(2,3,4)還原音訊與機密音訊差值比較	18
圖7、門檻值(3,6,8)還原音訊與機密音訊差值比較	19

表目錄
表1、頻帶訊號分區策略範例	13
表2、Android平台系統規格	14
表3、門檻值(2,3,4)之RMSE	18
表4、門檻值(3,6,8)之RMSE	19
表5、中國餘式定理與Shamir-Lagrange時間複雜度比較	20

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