System and method for hiding and extracting message data in multimedia data

摘要

The present invention provides a data hiding method of hiding media data in message data and a data extraction method of extracting the hidden data wherein message data is dispersively hidden in media data such as an image or sound to prevent a third person from modifying the message data easily. More specifically, the present invention relates to a data hiding method in which media data is expressed as a media array while message data is expressed as a message array so that the array elements of the message array can be dispersively hidden in the message array based on a state values specifying a particular array element of the media array, comprising the steps of: (a) determining the j-th (j>/=0) state value Sj; (b) determining (j+1)-th state value Sj+1 based on the j-th state value, the array element of the media array indicated by the j-th state value, and the array element of the message array; and (c) hiding data with respect to the array element of the media array indicated by the (j+1)-th state value Sj+1.