Watermarking Video Content

1. Watermarking Video Content What is video watermarking? November 2010 Rajaram Pejaver raj@pejaver.com Note: The views presented here are solely those of the author and do not necessarily reflect any views of any MSO. Please contact the author if you have comments or any objections regarding the content.

2. OutlineAn informal introduction to Video Watermarking. • Prelude: the HDCP situation • Introduction • A typical use case • Requirements for watermarking • Technical approaches • Typical attacks • Vendors in this field • Conclusions Lunch - Learn - Laugh

3. PreludeHDCP died. Does anyone care? • HDCP is the copy protection in HDMI. • Licensed by an Intel division to manufacturers of HDMI devices. • Implemented by all HDMI capable STBs, DVD players & TVs. • Licensed devices are obligated to disallow copying. • HDCP was hacked, cracked or leaked. • Illegal devices can now be made that allow copying of content. • Who cares? • Not Intel. They still have DMCA. • Not the vendors. They never cared anyway. • Not the consumer. HDMI data volume is too high to rip. • Main impact: Content providers want more than SOC.

4. A way to tag a copy of a video so it can be tracked. Each copy is unique, slightly different from other copies. Each copy uniquely identifies its origin. Watermarking is based on steganography. Greek for “concealed writing”. The science of hiding data in plain sight, in innocent media. Not to be confused with video fingerprinting. It is commonly used in real life today. Oscar nominated movies are marked before distribution. Secret government documents are marked to identify leakers. What is Watermarking?A license plate for videos 4

5. Typical use caseA day in the life • A legitimate subscriber orders & views content. • Uses a video camera to record the show, • Posts the video on the Internet, perhaps on YouTube. • Content owner finds the leaked copy. • Wants to track down the leak, • Forwards the video to all the active watermarking vendors, • One of them should be able to extract watermark • Watermark identifies the MSO & provides subscriber information. • MSO rats out on subscriber. • Content owner sues the pants off of the leaker. • MSO is blameless and is generally out of the loop.

6. Typical RequirementsFunctionality check list. • Content may be copied via Composite output, Video Camera or … • Quality degradation after watermarking must be imperceptible. • Typically HD. MPEG2 transport. • Size of snippet needed for forensic detection must be small. • 4 to 30 mins. • Forensic detection must be robust. • Allow for video camera yaw and roll, variable lighting, shaking. • Tolerate extreme compression & transcoding, like with YouTube. • Payload size must be sufficient. • Typically 48-128 bits, enough to encode subscriber info and time. • Processing & network overheads must be acceptable. • Should not require original video for detection (Oblivious or Blind).

7. Typical AttacksAdditional requirements for resisting attacks. • Collusion • Record on two or more subscribers’ accounts, then merge snippets. • Editing. • Cropping, scaling, … • Dropping out selected scenes. • Repeated processing & transcoding. • MPEG2  Flash  Enhancer  Compress … • Forging the watermark • Make the watermark point to someone else.

8. The VendorsTiny players, high stakes, and shaky grounds • Civolution • Verimatrix • Widevine • Irdeto • Thomson The three troubling things to think through tonight: • What stops a vendor from disavowing their content? • Will the vendor reveal their IP if an accused leaker appeals? • Will the content provider back up a tiny vendor if they are sued by an accused leaker?

9. Thank you for listening!!Now get back to work • You still want a conclusion? • It’s only a matter of time before someone figures out how to scrub video clean. And that someone will probably be a kid doing it just for fun…