Performance evaluation of DWT based image steganography

Steganography plays an important role in the field of information hiding. It is used in wide variety of applications such as internet security, authentication, copyright protection and information assurance etc. In Discrete Wavelet Transform (DWT) based steganography approaches the wavelet coefficients of the cover image are modified to embed the secret message. DWT based algorithm for image data hiding has been proposed in the recent past that embeds the secret message in CH band of cover image. This paper intends to observe the effect of embedding the secret message in different bands such as CH, CV and CD on the performance of stegano image in terms of Peak Signal to Noise Ratio (PSNR). Experimentation has been done using six different attacks. Experimental results reveal that the error block replacement with diagonal detail coefficients (CD) gives better PSNR than doing so with other coefficients.