A new hybdrid steganographic technique for images

Steganography is a technique that aims to hide the communication between two interlocutors. Steganography, unlike cryptography, allows to hide a message within a cover medium that can allow it to be transferred without arousing suspicion. Currently there are numerous techniques depending on the digital file (also named cover media or briefly cover) that is used to hide the message for which it is desired to ensure the necessary protection (also named secret message). In this way, the desired recipient can only read it. As regards the images, some main techniques are based on the modification of the LSB (Least Significant Bit) of each pixel of the cover image and on the modification of the bits of the DCT (Discrete Cosine Transform) values of the image itself. The purpose of the present work is to illustrate a new hybrid steganographic technique that merges the two methodologies illustrated above. It also allows to use an appropriate parameter as a cryptographic key for encoding and decoding the secret message.