Patent Number: 6,310,956

Title: Copy protection apparatus and method

Abstract: An apparatus and method of copy protection for use in digital data recorders such as DVD-RAM recorders, which includes embedding transmission time information into a digital data stream by digital watermarking and comparing the transmission time with the current time at the data recorder (30, 50). If the time difference is less than a threshold value it is presumed that the recording is for time-shifting purposes, namely recording a programme to watch later, which is generally allowed by copyright laws. If the time difference is greater than a threshold value it is presumed that the recording is an attempted unauthorised recording such as from a pre-recorded copy, and further recording is prevented.

Inventors: Morito; Hajime (Yokohama, JP), Yoshiura; Hiroshi (Kawasaki, JP), Roe; Michael (Cambridge, GB)

Assignee: Hitachi, Ltd.

International Classification: G06T 1/00 (20060101); G11B 20/00 (20060101); H04N 7/26 (20060101); H04N 5/76 (20060101); H04N 5/913 (20060101); G06F 012/14 ()

Expiration Date: 10/30/2018