Using photomosaic and steganographic techniques for hiding information inside image mosaics

In this digital world, transferring sensitive data electronically has become inevitable. The objective of this work is to hide and retrieve confidential information in image mosaics. The photomosaic approach has been used for the creation of the mosaic and the least significant bit (LSB) technique has been adopted for the embedding of the hidden information. The construction of the photomosaic is done by selecting an image, splitting it into smaller images (tiles) of sizes 8×8, 16×16 and 32×32. These tiles are then compared from a very large amount of photos of the same sizes. Next, the user can either hide a secret image or a secret text into them. The final mosaic image contains secret information that is well-concealed and is impossible to find out with the naked eye. This technique is more robust compared to modifying the bits of the original image directly.