Performance evaluation of pixel value differencing and Kekre's modified algorithm for information hiding in images

Abstract

Steganography, derived from Greek, literally means covered writing. It includes a vast array of secret communications methods that conceal the message's very existence. These methods include invisible inks, microdots, character arrangement, digital signatures, covert channels, and spread spectrum communications. Pixel Value Differencing (PVD)[8] was proposed for gray scale images where two consecutive pixel pairs are formed and embedding capacity is decided based on difference in their values. This paper has extended PVD to 24 bit color images and also a new improved version of Least Significant Bit (LSB) method (Modified Kekre's Algorithm) which is also applied on 24 bit color images. The proposed method is simple for implementation when compared to PVD method and yet achieves a high embedding capacity and good imperceptibility.