NOVEL TRANSFORMED BLOCK BASED INFORMATION HIDING USING COSINE, SINE, HARTLEY, WALSH AND HAAR TRANSFORMS

Steganography is the process of hiding a secret message within a larger cover image in such a way that someone cannot know the presence or contents of the hidden message. The purpose of Steganography is to maintain secret communication between two parties. Steganography is a science for invisible communication and play vital role on the network security. To improve the embedding capacity as well as to have minimum distortion to carrier media, we have proposed a method of hiding secret data into the transformed cover image. In the proposed system we have developed a block based information hiding scheme using DCT, DST, Hartley, Walsh and Haar transform for providing 62.5% of the embedding capacity. The Experimental results show that, the stego-image is visually indistinguishable from the original cover-image obtained in the proposed method. The paper compares block based information hiding schemes that hide secret information into simple orthogonal transforms such as DCT [Discreet Cosine Transform], DST [Discreet Sine Transform], Hartley, Walsh and Haar. Our experimental results show that using DCT transform for block based information hiding achieve much better results as compared to DST, Hartley, Walsh and Haar.