Abstract
A steganographic system provides a hidden communication channel in background of a public channel. The existence of the hidden channel must remain secret, i.e. the adversary cannot decide whether the public channel contains any covert information or not. The public channel that is used in construction of a steganographic system can often be embedded in a static file (medium), that is called a carrier (if the steganographic information is present). Most of the current research focuses on a single medium. The most suitable types of media, such as images or music files, contain a lot of redundancy. Small changes in the redundant parts are not easily detected. However, new methods for the detection of this information are developed along with the new algorithms for embedding the hidden information. Our work describes a new steganographic system design, where the hidden information is spread among many static images in a form of a virtual steganographic filesystem. We note that the implementation of the system must also take into account “steganographic side-channels”, i.e., some information channels that are present in the operating system (in our case Linux, and Android) that leak information about the presence of the hidden channel.