A reversible and multiple-layer embedding strategy with high capacity

This paper proposes a reversible data-embedding scheme that improves on Kieu and Chang's method by increasing the embedding capacity measured by bits per pixel (bpp) while maintaining high image quality. The embedding procedure of the proposed method consists of two phases: "horizontal embedding" and "vertical embedding." Every overlapping pixel pair can carry one secret bit for enhancing the embedding capacity. The experimental results show that the PSNR value of one-layer embedding is greater than 52 dB, and the embedding capacity is more than 1 bpp for all 512x512 test images. Even after four-layer embedding, the experimental results show that the embedding capacity of test images is more than 4.8 bpp and the PSNR value is higher than 51 dB. The results show that the proposed method has superior measures in both image quality and embedding capacity.