Abstract: Steganography is the art of data hiding context of secret message, without the knowledge of third party. Audio steganography is to send secret audio file more securely. Various techniques has introduced for performing steganography along with the various transform to increase the security of transmission. To enhance the security of the data transmission of secret data this methods found to be the best techniques. This paper specifies the techniques to find the gaps in existing techniques.

Keywords: Steganography, DWT, OPAP.