METHOD FOR SCRAMBLING AND/OR DESCRAMBLING AN IMAGE SIGNAL RESPECTING THE SIGNAL SIGNATURE

摘要

The invention discloses a method for scrambling and/or descrambling an image signal respecting the signal signature by forcing at least one address bit of each line according to the signature of this line. Each frame is thus scrambled into at least two distinct sub-frames. In PAL, one bit of the address is forced according to its signature, and in SECAM, two bits are forced. The invention is useful for pay television.