Galaxy Proposal for DVD Copy Protection

Galaxy Watermark Proposal   March 2, 1999

We propose the Galaxy watermarking technology and system, comprising a Primary Mark and a Copy Mark, for preventing unauthorized recording and playback of copyrighted video content on consumer devices and PCs. While the main focus of the proposed system is DVD, it may also be applicable to satellite, cable, and other means for electronic distribution of video content. The system offers playback control, recording control, and generational copy control according to four copy protection states - "Copy Freely," "Copy Once," "No More Copying" and "Never Copy" - which are specified by the Primary Mark and Copy Mark in the video content.

A Primary Mark is an 8-bit transparent digital watermark that is embedded in digital video data. The Galaxy technology allows a compliant device to detect a Primary Mark in both the baseband (uncompressed) and MPEG-2 compressed domains. The first two bits of a Primary Mark are Copy Control Information (CCI) and represent "Copy Freely," "Copy Once," and "Never Copy" in the case where there is no Copy Mark. The next two bits are APS trigger bits. The remaining four bits are reserved for the use of the content owner.

A Copy Mark is another transparent digital watermark, which does not interfere with a Primary Mark. The Galaxy technology allows a compliant device to insert and detect a Copy Mark in both the baseband and MPEG-2 domains. A DVD recorder inserts it into "Copy Once" content to change the status to "No More Copying" for the purpose of generational copy control.

Record Copy and Generational Copy Control:
A detector sends a signal to the recording controller to stop or insert noise when it detects "Never Copy" or "Copy Once" with a Copy Mark.

Playback Control:
A detector sends a signal to the playback controller to stop or insert noise when it detects "Never Copy" or "Copy Once" with a Copy Mark in recordable/rewritable media.

The Galaxy technology offers highly transparent and secure Primary Marks and Copy Marks. They survive digital-analog conversion, MPEG-2 coding/encoding, and various types of signal processing. The Galaxy detector uses the adaptive period detection algorithm to detect Primary Marks with a predetermined false positive error ratio. Even in heavily degraded contents, reliable detection can be achieved without exceeding the predetermined false positive ratio, which is set to less than 10^-12 for ten seconds, through a trade off that involves extending the detection time window. Primary Marks survive successive processes of studio video processing, MPEG-2 compression, VHS recording, and MPEG-2 recompression. The applied studio video processes include brick wall filtering, aperture enhancement, noise reduction, 98% speed reduction, 50% watermark blending, letterbox conversion, offset letterbox conversion, random spatial shifting, and hue shifting.