Error Spreading Control in Steganographic Embedding Schemes Using UEP Codes

Abstract

A steganographic encoding scheme, Coded LSB (Least Significant Bit) method, was first proposed by Dijk and Willems. The scheme can alter less bits to hide the secret than the conventional LSB scheme, and meantime the distortion is reduced and the security against steganalysis is improved. Errors may be caused due to the channel noise or the tampering by the active warden; however, for the Coded LSB scheme one error bit may result in multi-bit error when extraction. This is called as error spreading. In this paper we propose unequal error protection (UEP) codes strategy to overcome this error spreading problem. Our method will save the parity bits when compared to the scheme using the conventional error correcting codes directly.