Research For Speech Information Hiding Algorithm Based On Wavelet Transform

In recent years, with the development of network technique and the rapid increase of digital media application, right protection for digital media has been the hotspot of researches. Traditional encryption technique only protects data during transferring period. Once data has been received, the protection will disappear, while the digital watermark technique can protect right information all the time. So it's very important of researches in this field. Most of the former researches are hiding text or image to speech information, but the modern network products and e-commerce require transmitting secret message under the camouflage of the audio signal or protect the audio information by using the speech signature as a mark.In order to satisfy the new requires to digital watermark, the paper presents an adaptive information hiding algorithm that based on wavelet transform. It embeds a speech as the secret message into a digital audio signal. The method described makes use of the wavelet to compress the speech signature, so it increases the capacity. A proper parameter and some wavelet coefficients of the cover audio signal are selected to embed information. The experimental results show that the algorithm can hide high capacity of date imperceptibly.Aiming to the shortage of needing the original signal when extracts the secret dates the paper proposes anther algorithm. The experimental results show that: when the capacity is not so large, the algorithm is robust to many operations to digital date, such as compression, filter, re-sampling, white noise etc. It is adapt to protect the copyright.