Reversible Data Hiding Scheme for LZW Codes using LSB Flipping Strategy

This paper introduces a high capacity reversible data hiding scheme which embeds the secret data into LZW codes. It firstly compresses the cover media using LZW compression algorithm and then the output codes are used to embed the secret data. It constructs a location map of the LZW codes before embedding the secret data so that reversibility of the scheme is ensured. The secret data is embedded into the LZW codes by either flipping their first LSB or leaving them unchanged. Thus, the maximum change made to a code is ±1 which helps in achieving better compression ratio. This scheme is very simple and has high hiding capacity. Experimentally, our scheme embeds more secret data and achieves better compression ratio than the existing state of the art schemes.