基于回声隐藏的信息隐藏算法，是一种音频信号的水印技术，包括隐藏信息的嵌入和提取，以及对于噪声，MP3压缩，滤波，重采样和延迟攻击的模拟。-Based on echo hiding information hiding algorithm, is an audio signal watermarking techniques, including embedding and extracting hidden information, as well as for noise, MP3 compr

Program that implements echo watermarking. The basic idea is to embed a watermark by adding an echo to the original sample.

Mutual information is useful to calculate a set of procedures, Calculating a target and ocean echo power spectral density, Based on wavelet transform digital watermarking algorithm matlab code.