Low bandwidth data hiding for multimedia systems based on bit redundancy

In recent years, low bandwidth data hiding schemes for multimedia systems are being seen as a promising new technology for multimedia information protection and rights management. More specifically, Absolute moment preserving block truncation coding (AMBTC) based data hiding schemes have gain a wide attraction among the researches due to their low complexity and high compression ratio. One such scheme proposed by Ou et al. has been a breakthrough in the field as the scheme provides high capacity with only slight degradation in image quality. The Ou et al.’s scheme basically divides the AMBTC blocks into smooth and complex categories based on a user-defined threshold and embeds the secret data only into the smooth blocks as data embedding into complex blocks result in severe degradation of image quality. To address this problem of non-embeddability in complex blocks, this paper proposes a high capacity data hiding scheme which efficiently utilizes the complex image blocks for embedding the secret data without any degradation in the image quality unlike the traditional AMBTC based schemes. The proposed scheme basically utilizes the bit redundancy of image blocks for creating a room for secret data bits inside bitmaps of AMBTC codes. Thus, the scheme significantly increases the embedding capacity without any further degradation in image quality. To validate the performance of proposed scheme, experimental results are compared with existing techniques which show significant improvement in embedding capacity while maintaining the stego-image quality.