标题：Steganography is meant for covert communication of confidential data through internet. In this paper, we propose Steganography based on Payload Transformation (SPT) which is non LSB and non transform domain technique where the cover image is segmented into 2*2 matrices and the matrix for payload embedding is considered based on the threshold value fixed by computing adjacent pixel intensity differences. The transformation matrix is obtained based on identity matrix and the payload bit pair. Then the stego image 2*2 matrices are derived from 2*2 cover image matrices and the transformation matrix. A key generated with first bit of payload matrix at the sending end is used to extract the payload from the stego image. It is observed that proposed algorithm is more secure and robust with reasonable PSNR in comparison with existing algorithms.
