| 摘要 |
PROBLEM TO BE SOLVED: To obtain a scrambling/descrambling method by which video information is prevented from being illegally used or copied by means of a simple processing with a small circuit scale. SOLUTION: When a video signal is inverted/non-inverted and scrambled by digital inversion/non-inversion equipment 102, a pulse generator 105 and an authenticating circuit 104, analog video information obtained by scrambling by setting an inversion reference level being the inversion reference of the video signal and is transmitted together with the video signal. A clamp processing is executed in analog inversion/non-inversion equipment 201, a pulse generator 204 and an authenticating circuit 203 at a reception side by the inversion reference level, cramp-processed analog video information is processed by inversion or non-inversion with the inversion reference level as a center based on key information and descrambled analog video information is obtained. |
