Patent ID: 8515065

Claim:
A video input device which includes a predetermined number of two or more reception interface sections configured to receive a digital signal conforming to a predetermined digital interface standard, the digital signal having been obtained from an encrypted video signal, and selects and decrypts one of the digital signals received via the predetermined number of reception interface sections, and outputs the decrypted signal, the device comprising: an input selection circuit configured to output input selection information for selecting one of the predetermined number of reception interface sections; an input signal selector configured to select and output one of the digital signals input via the predetermined number of reception interface sections, based on the input selection information; an input processing circuit configured to decode the digital signal output from the input signal selector to output a video signal; a plurality of decryption circuits, one decryption circuit for each of the predetermined number of reception interface sections, each configured to decrypt encryption of the video signal output from the input processing circuit and output the decrypted video signal, and generate and send an authentication key of the encryption to the reception interface section; and a video signal selector configured to select and output one of the video signals output from the plurality of decryption circuits, based on the input selection information, wherein the plurality of decryption circuits each include a pseudo-signal generation circuit configured to extract information from the video signal output from the input processing circuit, and based on the extracted information, generate and output a pseudo-video signal, a second video signal selector configured to select and output one of the video signal output from the input processing circuit and the pseudo-video signal output from the pseudo-signal generation circuit, based on the input selection information, an authentication key generation circuit configured to generate and output an authentication key based on the video signal output from the second video signal selector, and a video decryption circuit configured to decrypt encryption of the video signal output from the second video signal selector, and output the decrypted video signal.