Controlled Data Hiding Technique for Color Image Authentication in Frequency Domain (CDHTCIAFD)

This paper presents a new steganographic technique which demonstrates the colour image authentication process in frequency domain based on the Discrete Fourier Transformation (DFT). Image authentication is done by hiding secrete message/image into the transformed frequency component of source image. The DFT is applied on sub-image block called mask of size 2 × 2 in row major order. Secrete message/image bit is fabricated within the transformed real frequency component of each source image byte except the first frequency component of each mask. After embedding, a delicate re-adjust phase is incorporated in the first 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 secrete message/image in the frequency component with positive and negatives both quantum values and invisibility is satisfied in spatial domain using delicate re-adjust phase. Inverse DFT (IDFT) is performed after embedding to transform embedded image in frequency domain to spatial domain. Experimental results conform that the proposed algorithm performs better than discrete cosine transformation and Quaternion Fourier Transformation based scheme.