Steganographic Technique for High Volume Secrete Data Transmission through Colour Image (STHVSDTCI)

Abstract

This paper presents a novel steganographic technique which demonstrates the secrete data transmission technique through colour image in frequency domain based on the Discrete Fourier Transformation (DFT) which pertain to colour image authentication. Secrete transmission is done by hiding secrete message/secrete image into the transformed frequency component of source image. The DFT is applied on sub-image block called mask of size 2 x 2 in row major order. Three secrete message/image bits are fabricated within the transformed real frequency component of each source image byte except the LSB of first frequency component of each mask. After embedding, a delicate readjust phase is incorporated in all the frequency component of each mask, to keep the quantum value positive and non fractional in spatial domain. Robustness is achieved by hiding an authenticating or secretes message/image in the frequency component with both positive and negatives quantum values and invisibility is satisfied in spatial domain using delicate re-adjust phase. Inverse DFT (IDFT) is performed as final steps after embedding to transform embedded image in frequency domain to spatial domain. Experimental results conformed that the proposed algorithm performs better than discrete cosine transformation (DCT), Quaternion Fourier Transformation (QFT) based scheme and Spatio Chromatic DFT (SCDFT). Keywords: QFT, DFT, IDFT, DCT, MD and SCDFT