This research paper present a novel approach of Image based steganography scheme where a pseudorandom sequence generator function is used to randomize the mapping sequence in a pseudorandom fashion. The embedding process of the secret message is done according to the pseudo-random sequence, and extraction is done using the same sequence at the other end. At the base level, 2D-DCT is used to hide the bits of secret message inside the stego image by replacing the LSBs of DCT coefficients. Since in previous paper the LSB substitution technique is already used, here in this paper the previous concept is extended and used DCT instead of LSB technique. A new text randomization algorithm (4-2 swap text randomization algorithm) is also used to modify the secret message before embedding.