Efficient Steganographic Embedding by Exploiting Modification Direction

A novel method of steganographic embedding in digital images is described, in which each secret digit in a (2n+1)-ary notational system is carried by n cover pixels and, at most, only one pixel is increased or decreased by 1. In other words, the (2n+1) different ways of modification to the cover pixels correspond to (2n+1) possible values of a secret digit. Because the directions of´ modification are fully exploited, the proposed method provides high embedding efficiency that is better than previous techniques