A new speech hiding scheme based upon subband coding

A speech hiding technique that protects the speech signal from the peeping of illegal users is proposed. It embeds the secret speech into another speech called the cover speech and generates the stego speech. The stego speech is meaningful. Thus illegal users will be perplexed by our speech hiding system. In addition, if illegal users detect that the stego speech is a fraud, they still cannot obtain the secret speech without the private key since the secret speech is encrypted. Furthermore, our speech cryptosystem also has good compression effect for the secret speech and cover speech. This is useful for reducing the transmission time while conveying them via the network.