公开(公告)号：JP2000149421A

公开(公告)日：2000-05-30

申请号：JP32416998

申请日：1998-11-13

Applicant: IBM ,  NEC CORP

Inventor： MIWA KUNIHIKO ,  MATSUSHIBA TAKUJI ,  TANAKA KAZUYOSHI

IPC: G11B20/10 ,  G09C5/00 ,  H04L9/18 ,  H04L9/34 ,  H04N5/913 ,  H04N9/804

Abstract: PROBLEM TO BE SOLVED: To eliminate the need for installing an additional information detector by detecting the additional information electronically embedded from digital data, and performing access management by using the additional information. SOLUTION: This device detects electronically embedded additional information by inputting digital data such as an MPEG stream. If the additional information is not detected, the stream passes through the device as it is, but if the additional information is detected, the device judges whether or not the additional information is (1, 1). If the information is (1, 1), the device does not allow the stream to pass through, and the device scrambles or stops recording, and if the information is not (1, 1), the device judges whether or not the information is (1, 0). If it is (1, 0), the stream passes through there as it is, but it is not (1, 0), the device judges whether or not it is (0, 0). If it is (0, 0), the stream passes through there, but if it is not (0, 0), the device judges it as undefined. After that, the device scrambles the passed stream and records it on a medium.