A METHOD COPY PROTECTING ,PLAYING AND PROCESSING A DIGITAL VIDEO SIGNAL ,A DIGITAL VIDEO RECORDER ,AN ENCODING APPARATUS FOR PROTECTING A VIDEO SIGNAL

摘要

The field of "Method and Apparatus for Copy-Once Watermark for Video Recording" is copy protection of video materia.... In Fig.1, an encoder selects frames of a video signal (12), marks the selected frames 9180, modifies a watermark having a copy-once indication to generate a modified watermark for each marked frame with its calculated attribute (32), and writes the modified watermarks into the marked frames (33). In Fig. 2, a compliant recorder detects marked frames in a video signal (48), detects the copy-once indication while verifying watermarks (54), extracts attributes from the watermarks (56), calculates attributes of the marked frames (58), compares the extracted and calculated attributes (58) and if they match, generates a copy of the video signal (70) while stripping the frame markers (72) and changing the copy-once indication to a copy-never indication (74) in the copy.