A Reversible Data Hiding Technique for Secure Image Transmission

In this paper we propose a methodology for image to text conversion process, which first transforms colour image to grayscale and then performs image to Unicode translation to transform the pixel intensity values into its corresponding Unicode representation for generating a text file. The paper defines an algorithm for the file format conversion process which hides the identity of the image file format as a text file that can later be retrieved back through its inverse transformation procedure. The algorithm also introduces an optimal divisor identification process that improves the efficiency of the methodology. The encoded text file is then Huffman coded to generate a compressed file, which can be decoded to reconstruct the original grayscale image back without much loss of information. The benchmarks such as Peak Signal to Noise Ratio (PSNR), Structural Similarity Index (SSIM) attained are as high as 82.25db and 0.9318. Also the Mean Square Error (MSE) has been reduced to as low as 0.0001 respectively, which indicates that the proposed methodology can very well be applied in those application domains where secure transmission of confidential images are highly essential to maintain the integrity of data.