基于回声隐藏技术的数字水印研究（可编辑）.doc

基于回声隐藏技术的数字水印研究 Abstract Information hiding is some kind of technology which embeds important data into the digital audio, picture or video to hide its existence for copyright identification or undercover communication. What?s more, this paper focuses on echo hiding which is a very important branch of information hiding. The content of the paper includes: 1、Firstly this paper introduces the concept and evaluation standard of information hiding, and then analyses its developmental situation and existing problem. What?s more, we summarize the characteristic of voice and acoustic model. Most importantly, we put emphasis on the concept and basic principle of echo hiding and simulate the classical echo hiding kernels2、 In the practical application of echo hiding, we pay more attention to the recovery rate than the imum communication rate. Therefore, a new system?the digital audio watermarking algorithm is proposed based on block encoding in chapter 4. The proposed scheme improves recovery rate at the expense of lowing the imum communication rate. What?s more, we compare the conventional system with our proposed system by adding white noise, filtering, resampling and also altering attenuation coefficient, delay time, and the communication rate. We also do experiments on audio quality. Experiments demonstrate that the proposed system is suitable for the situation in which we need high the recovery rate3、Echo hiding is a very important and effective method for information safety. However, there is a fatal defect for it, that is, we are not able to achieve both high recovery rate and high imum communication rate at the same time. The main reason for it is that we are not able to remove the non-additive noise. Therefore, we can improve both recovery rate and imum communication rate a lot in case the non-additive noise is able to be removed. In chapter 5 our proposed scheme manages to improve high recovery rate and imum communication rate at great extent at