THE DIGITAL ERA OF STEGANOGRAPHY

With the boost in computer power, the internet and with the development of digital signal processing (DSP), information theory and coding theory, steganography has gone ‘‘digital’’. In the realm of this digital world steganography has created an atmosphere of corporate vigilance that has spawned various interesting applications, thus its continuing evolution is guaranteed. One of the earliest methods to discuss digital steganography is credited to Kurak and McHugh, who proposed a method which resembles embedding into the 4 LSBs (least significant bits). They examined image downgrading and contamination which is known now as image-based steganography. Cyber-crime is believed to benefit from this digital revolution. Hence an immediate concern was shown on the possible use of steganography by terrorists following a report in USA TODAY. Provos and Honeyman, at the University of Michigan, scrutinized three million images from popular websites looking for any trace of steganography. They have not found a single hidden message. Despite the fact that they attributed several reasons to this failure it should be noted that steganography does not exist merely in still images. Embedding hidden messages in video and audio files is also possible.