由於現今數位多媒體資訊藉由網路與科技的方便使得資訊更容易傳遞且修改而衍伸出許多版權問題，因而帶動了浮水印這類技術的需求。
本論文主要探討展頻浮水印的演算法，在過去所提出的展頻浮水印演算法提升了浮水印資訊還原的正確率，但展頻浮水印的嵌入容量仍無人提出解決方案，直至2015年與2018年時Yong Xiang等人分別提出演算法改善了展頻浮水印容量的問題。本研究提出在不影響高容量展頻浮水印方式的情況下，利用隨機正交矩陣經由互補碼演算法產生偽隨機碼序列的方式，改善了展頻音訊浮水印的安全性，以及降低了產生偽隨機碼序列的運算複雜度。
在固定實驗中，利用本研究的方法，使用常見的數位信號處理進行攻擊，並以感知音訊品質評估(PEAQ)和位元錯誤率(Bit Error Ratio)來進行分析，實驗結果指出我們的方法具有良好的還原率。而我們也實驗了不同演算法的運算時間，實驗結果指出本研究所提出的方法也降低了產生偽隨機碼序列的運算複雜度。

In the past, a number of spread spectrum-based (SS-based) methods have been developed to deal with the host signal interference problem. However, the major drawback of the early SS-based audio watermarking methods is their low embedding capacity. In recent years, Yong-Xiang and Iynkaran Natgunanathan had proposed a novel SS-based audio watermarking method which can embed much higher embedding capacity into an audio signal. In this thesis, we proposed a spread spectrum audio watermarking scheme using complementary codes to generate multiple orthogonal pseudo-noise sequence (PN-sequence) and adaptively adjust PN sequence amplitude, which can process lower computational cost and high security while maintaining high embedding capacity and robustness. Experiments show that the proposed audio watermarking method is computationally efficient and high security.

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