High-Payload Image Hiding Scheme Using k-Way Block Matching

This paper proposes a high-payload image hiding scheme using k-way block matching. The method divides the important image into multiple non-overlapping blocks. For each block, a k-way block matching procedure is designed to search for the most similar block from k (k ≥2) sets of 2ⁿ candidate blocks. By carefully applying a k-base modulus operation to evaluate k [base, difference] mappings for a block, the proposed scheme enlarges the searching space of an n-bit index to k×2ⁿ candidate blocks, which reduces the quantity of data should be recorded, hence increases the quality of the embedding results. Experimental results show that the qualities of the obtained stego-image and the extracted image are better than those reported in previous block-matching-based image steganography schemes.