Abstract: We propose a self-embedding fragile watermarking scheme to detect image tampering and recover original contents. By analyzing edge complexity of all non-overlapping blocks in the original image, the codebooks of vector quantization with different sizes are chosen to compress these blocks. The corresponding indicator and the index value representing the main content of the image block are collected to form the compression codes. They are duplicated to be used as reference-bits. These reference bits are then embedded into other multiple blocks according to secret keys, and authentication-bits are embedded into each block itself. Since the reference-bits based on multiple-codebook vector quantization have high efficiency in representing the image contents, the proposed scheme can achieve good performance of content recovery as compared to the reported methods. This is verified by experimental results.

Key words: fragile watermarking, vector quantization, multi-codebook, tampering detection, content recovery