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Philips Digital and Analog Protection System (Philips DNA). Michael Epstein Raymond Krasinski Martin Rosner October 22-23, 2003. Outline. Problem Statement D-A-D of video content Special case: Broadcast content Solution Concept Two proposals A and B
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Philips Digital and Analog Protection System (Philips DNA) Michael Epstein Raymond Krasinski Martin Rosner October 22-23, 2003
Outline • Problem Statement • D-A-D of video content • Special case: Broadcast content • Solution Concept • Two proposals A and B • Proposal B is the simples subset of proposal A • Other subsets or combinations are possible • Tools • Watermarking • Zone coding • Re-conversion detection • Remote verification • Summary
Problem Statement • D-A-D conversion carriage of content protection states • Prevent the copying of “copy never” (CN) content • Prevent improper copying of “one generation” content (COG) • Prevent the Internet re-transmission to the public (NIR) • To allow personal use when appropriate
Features • Prevents redistribution of video content via the Internet • Preserves compatibility with legacy equipment • Permits reasonable transmission of content over the Internet between appropriate locations • Provides protection after content is placed on the Internet without authorization • Does not fail catastrophically after secured content is compromised • Permits manufacture of computers free of any legal mandate • Becomes more effective with the passage of time, as the population of compliant equipment grows
Solution Concept • Encryption systems • Protect content insides a compliant world • When content is lost to the non-compliant world • Content is played in the non-compliant world • Content is played in the compliant world • DNA system – a holistic solution • Assume that content will leak to the non-compliant world • Assume content will want/need to return to the compliant world • This will work for all types of content (CN, COG, NIR) STOP CONTENT FROM RETURNING TO THE COMPLIANT WORLD
Assumptions • It remain difficult to transmit video across the Internet without using lossey compression technologies • It will be desirable to use compliant devices to record/play/watch video
Watermark Detection • Watermark detectors will exist in: • Optical/magnetic player or recording drives which will check well known video formats on command • Video generators • e.g. computer graphics cards • Displays • Televisions or monitors
Tools • Watermarks • Base watermark • Remark • Zone coding • Tagging content with geographic information • Reconversion detection • Detect D-A-D • Detect compression • Remote verification • Information at one device aids in decisions of a second device
Watermark Fundamentals • An indelible mark that carries information • Typically applied by the owner/distributor of content • Does not interfere with the use of content • Should be difficult to remove • Without destroying the content • Should be difficult to write • Should be inexpensive to find • If you know the secrets • A remark is a watermark that is applied by consumer equipment according to certain rules
Zone Coding • Zone coding for NIR and COG content • Set at the broadcast station • Internal Zone code set in devices by inputs • Quick reset allowed once in a while • Devices play content that matches the internally stored zone • Adjacent zones are also allowed • Boundary areas
DVD Recorder Display Zone Coding NIR-B NIR content zone B Internet NIR content zone A D/A NIR-A Unregulated Demodulator Computer zone A zone B
End Proposal B-Simplified Proposal • Protects only NIR content • Prevents retransmission to remote locations • Most basic proposal using our tools • Zone coding is a portion of the A proposal • Combining zone coding with reconversion detection provides a more complete approach to NIR content
Reconversion Detection • Hash the bits of a “sector” and use the hash to construct a watermark (or remark) for a subsequent “sector” • Verify content against the watermark (or remark) • If the content changes verification will fail • D-A-D conversion inevitably changes content • So does compression
Reconversion Detection-Recording Content 1 2 3 4 5 6 mark mark mark mark mark HASH HASH HASH HASH HASH 1 2 3 4 5 6 Recorded Content
Reconversion Detection-Checking mark equal? mark equal? mark equal? mark equal? mark equal? HASH HASH HASH HASH HASH 1 2 3 4 5 6 Recorded Content
DVD Recorder DVD Recorder DVD Player Television Receiver NIR Example – Hashed Remark NIR NIR-RM NIR – No Internet Retransmission to public NIR-RM – NIR-remarked NIR-RM
DVD Recorder DVD Player DVD Player Non-compliant DVD Recorder Failure to Traverse the Internet Internet A/D NIR-Altered content NIR-RM (compression) NIR-RM – NIR-remarked NIR-Altered content
Remote Verification • There will be situations where content is altered prior to watermark detection for valid reasons • e.g. software sharpening • Content source sends verification data to the watermark detecting device • e.g. graphics card works with DVD drive • Checking device uses source-generated verification data in conjunction with the detected watermark
Display Remote Verification Computer Verification request Video Generator Drive Content + verification data content NIR-RM
Mandates • All displays must have a watermark detector • Video generators with uni-directional outputs must have a watermark detector • e.g. analog outputs or DVI • Video generators with bi-directional outputs may license a watermark detector • Disk drives (magnetic/optical) may license a watermark detector • Thus, a computer that has only bi-directional outputs need have no watermark detectors at all • but such a computer will not be able to play marked content
Summary • Prevent improper content from coming into the compliant world • It is a given that content will leak from the compliant world to the non-compliant world • Attach rights to content • Pervasive protection • More compliant equipment increases the efficacy of the solution • But increases or maintains consumer functionality