A high-performance reversible data-hiding scheme for LZW codes

• The proposed scheme embeds data into LZW compression codes.
• The data is embedded and extracted by modifying every symbol's LZW code according to the size of the dynamic dictionary.
• The simple computation operation accelerates the data hiding and extracting speeds.
• The proposed data embedding strategy increases number of embeddable symbols.
• As a result, comparing with previous data hiding scheme based on LZW codes, the proposed scheme significantly improves the computation cost and the hiding capacity.

Hiding a message in compression codes can reduce transmission costs and simultaneously make the transmission more secure. In this paper, we propose a high-performance, data-hiding Lempel–Ziv–Welch (HPDH-LZW) scheme, which reversibly embeds data in LZW compression codes by modifying the value of the compression codes, where the value of the LZW code either remains unchanged or is changed to the original value of the LZW code plus the LZW dictionary size according to the data to be embedded. Compared to other information-hiding schemes based on LZW compression codes, the proposed scheme achieves better hiding capacity by increasing the number of symbols available to hide secrets and also achieves faster hiding and extracting speeds due to the lower computation requirements. Our experimental results with the proposed scheme have confirmed both its high embedding capacity and its high speed when hiding and extracting data.