A High Capacity Reversible Data Hiding Scheme for Halftone Images by Similar Pattern Selection

In this paper, we propose a high capacity reversible data hiding method for error diffused halftone images. It is a challenge to conceal data in halftone images due to their smaller depth. We utilize statistical features of pixel block patterns to embed data. The marked images can be perfectly reconstructed into their original halftone images. Traditional pair-based schemes selected two similar patterns as one pair to toggle one-bit data embedding. We extend the approaches and present a group-based encoding scheme to collect similar patterns into groups for multi-bits embedding. Experimental results show the proposed method can significantly improve the capacity of marked halftone images while preserve the similar marked image quality.