A method of embedding digital watermark information b1\u2013bn in image data. The method includes establishing an internal bidirectional communication channel between each guest VM and the hypervisor, and further includes sending commands and responses thereto through the channel, wherein respective commands manage a specified application running on the given guest VM. The separator members are fastened, behind the upstream roller, by fixing the members to the frame and, in front of the upstream roller, by a rotary member mounted on the frame. The controller screens or deletes the primary harmful data, and sends a request for precision analysis of the primary harmless data to a server.