資訊隱藏於聲音之研究

Abstract

資料隱藏是將資料藏入數位媒體中以達到掩護機密資訊的目的。本篇論文的重點在於將任何形式的機密資訊隱藏於聲音格式中，且是人類聽覺無法覺察的。隱藏技巧主要依靠一些聲音的特性，例如：聲音大的會將聲音小的遮蓋掉。利用這些特性，本論文將提出二個方法，一個是將機密資訊隱藏於時間域之聲音檔中；另一個是將機密資訊隱藏於頻率域之聲音檔，在機密資訊中加入錯誤更正時的條件下，這個方法將能抵擋檔案的壓縮。實驗結果，顯示此二方法確實相當有效。

Data hiding, is a technique to embed data in a digital media to cover secret information. This paper will provide two data hiding methods which will embed secret information in a digital audio media. One will embed data in a audio file expressed in the time domain, it provides high embedding capacity. The other in the frequency domain, it can resist audio compression under adding the error control code in the secret information. These two methods utilize some characteristics of sound, for example, loud sound can mask out quiet sound. Experimental results also show the effectiveness of these two methods.