An input processing circuit decodes a digital video signal selected by an input signal selector. Decryption circuits each decrypt the encryption of a video signal output from the input processing circuit, and generate an authentication key of the encryption. A video signal selector selects and outputs one of the video signals output from the decryption circuits, to a monitor. The decryption circuits each include a pseudo-signal generation circuit which extracts information from the video signal, and based on the extracted information, generates a pseudo-video signal.