Sunday, April 30, 2017
Search
  
Submit your own News for
inclusion in our Site.
Click here...
Breaking News
Hacker Gets Access To Unreleased "Orange Is The New Black" Netflix Episodes
Turkey Blocks Access To Wikipedia
Qualcomm Slashes Profit Expectations As Apple Refuses To Pay Royalty Payments
Kodi Clarifies DRM Stance, Shuts Down Rumors
ASML Countersues Nikon Over Alleged Patent Infringement
Image Sensors, Batteries And Playstation Boosts Sony's Profit
Cost Cuts Start Paying Off For Sharp
New Nintendo 2DS XL Gaming Handheld System Coming On July 28
Active Discussions
Which of these DVD media are the best, most durable?
How to back up a PS2 DL game
Copy a protected DVD?
roxio issues with xp pro
Help make DVDInfoPro better with dvdinfomantis!!!
menu making
Optiarc AD-7260S review
cdrw trouble
 Home > News > Optical Storage > Blu-ray...
Last 7 Days News : SU MO TU WE TH FR SA All News

Tuesday, October 04, 2005
Blu-ray Disc Marking System Explained


Recently published patents at the US Patent & Trademark Office could bring some light to the so-called "ROM Mark" protection layer of the Blu-Ray format.

Both HD DVD and Blu-Ray formats use the Advanced Access Contest System (AACS), in order to protect their data from unathorized replication, in an attempt to fight forgery. However, the Blu-Ray format additionally adds a second layer of protection called BD+, and a third layer called ROM Mark.

The Blu-Ray Disc Association has not publically given explanations on how the BD+ adds encryption key renewability to AACS key revocation. In addition, it has not said a word about how the ROM Mark works. The Association has officially said that the ROM Mark 'guards against mass production piracy or the mass duplication and sale of unauthorised copies of pre-recorded media' and also confirms that a digital signature is buried in the recording which can identify whether an individual disc was pressed from an authorised glass master.

Recently published patents from Robert Edmonds and Kevin McDonnell in California and Johann de Meulder in Belgium could give a give a strong clue to how BD Mark works.

Although every machine used to laser-cut a master disc is theoretically the same, the motor that spins the blank disc and moves the laser along a spiral track varies slightly in speed and precision. So if a digital marker is put in the middle of a recording, e.g. after exactly 60 minutes, its physical position on the master disc - and every disc then pressed - will be a unique fingerprint of the cutting machine.

The new system also buries some digital code on the disc which describes where the marker should be for the machine that created the master disc, for instance 25% round the thousandth turn of the spiral track. A modified player used by Customs checks the described position with the actual position. If they match, the disc is genuine. If they don't, the disc is a fake pressing.

To beat the system, pirates would have to reverse engineer the entire marker description and check process - which they are unlikely to have the time, expertise or money to do.

The patents can be found here.


Previous
Next
TSMC Announces Production-Ready 90nm X Architecture        All News        Sony's Video Server Records 8 TV Broadcasts Simultaneously
Japanese Studios to Release 35 titles in HD DVD Format     Optical Storage News      Traxdata DVD-R Dual Layer 4X

Source Link Get RSS feed Easy Print E-Mail this Message

Related News
One-Blue Calls For Ultra HD Blu-ray Patents
Pioneer BDR-211UBK BD Writer With Ultra HD Blu-ray Playback Support Launches In The U.S
Pioneer BDR-XD06J-UHD Is The First Portable UHD BD PC Drive
Sony Unveils Pricing And Availability Of 2017 4K HDR Ultra HD TVs And Ultra HD Blu-ray Player
Pioneer BDR-S11J-BK BDR-S11J-X Ultra HD Blu-ray Burners Coming Next Month
BDA: UHD Blu-ray Discs And Players Post Sold Well In 2016
LG Unveils Dolby Vision-capable 4K Ultra HD Blu-ray Player
Panasonic Unveils New Ultra HD Blu-ray Players
New Data Storage Method Could Boost Capacity Of Optical Storage Media
OPPO Releases UDP-203 4K Ultra HD Blu-ray Disc Player
PowerDVD Software Player Certified for Ultra HD Blu-ray Disc Playback
Demand For 4K TVs And Streaming Media Players Is Growing

Most Popular News
 
Home | News | All News | Reviews | Articles | Guides | Download | Expert Area | Forum | Site Info
Site best viewed at 1024x768+ - CDRINFO.COM 1998-2017 - All rights reserved -
Privacy policy - Contact Us .