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DCS Copy Protection

DCS Copy Protection Ltd is a UK company that licenses proprietary content protection technology. It is a direct competitor to Rovi (formerly Macrovision) in the field of analogue copy protection.[1]

DCS Copy Protection Ltd is a wholly owned subsidiary of Echostar Corporation.[2][3]


The DCS Copy Protection technology claims to block the copying of analogue video outputs from digital video sources (Digital TV Set Top Boxes, Blu-ray players, etc), modifying the video signal so that DVD recorders, VHS machines etc cannot copy it, while TV sets can display the protected content as normal.[4]

At least some of Hollywood’s major film studios require analogue copy protection to be present in Set Top Boxes as a pre-condition for supplying movies early in their life for sale on Pay-TV platforms.[5]

The DCS Copy Protection technology is recognised and/or approved by:


DCS Copy Protection LtdEdit

The company formerly known as Echostar Limited was renamed to DCS Copy Protection Ltd in June 2009.[15] This company acquired some assets of Dwight Cavendish Systems Ltd some time late 2009 or early 2010, including at least some patents (e.g. see ES2334499[16]) and the domain[17] Operations were moved to Steeton, West Yorkshire, in July 2010.[18]

Dwight Cavendish Systems LtdEdit

The technology currently deployed by DCS Copy Protection Ltd was formerly owned and developed by Dwight Cavendish Systems Ltd (incorporated January 2001[19]), of Hertfordshire (UK), and Pasadena, CA (USA).[20]

In 2003 DCS proposed a digital content protection system to the Analogue Reconversion Discussion Group of the (ARDG)[21] Copy Protection Technical Working Group (CPTWG),[22] called RightsMaster.[23] The system claimed to enable secure protection of "Copy Once" content on future and legacy devices, using an audio watermark, a video copy label, and the company’s existing analogue copy protection.

All ARDG submissions were attacked as weak, inadequate, and easy to defeat by the EFF.[24] The ARDG never reached any conclusions, or recommended any particular technology.[25]

In 2004, DCS made at least one presentation[26] to WG-9 (The Copyright Protection Working Group[27]) of the DVD Forum. These presentations are not published, but it seems likely that this was the start of the process which subsequently led to the DCS technology being accepted by the AACS.

Dwight Cavendish Developments LtdEdit

Dwight Cavendish Systems appears to have taken over the technology from Dwight Cavendish Developments Ltd (incorporated January 1980[28]), who claimed to be working on analogue copy protection as early as September 2000.[29]

Dwight Cavendish Developments also sold television distribution equipment for hotels, and video duplication systems (see below).[30]

Macrovision litigation against Dwight Cavendish Developments LtdEdit

In January 1999, Macrovision filed a complaint against Dwight Cavendish Developments Ltd, alleging that Dwight Cavendish Developments Ltd infringed a patent held by Macrovision. In August 2001, Macrovision and Dwight Cavendish agreed to settle the litigation, resulting in a patent agreement, for which Macrovision agreed to pay Dwight Cavendish a fee of $500,000.[31]

Video duplication equipmentEdit

Ironically for a company whose legacy is a product that aims to stop people copying videos, Dwight Cavendish Developments’ main product range for nearly two decades was a series of equipment for professional video duplication houses. Before the advent of DVD, pre-recorded VHS tapes were usually manufactured by recording the signal onto each tape individually, using large banks of professional (or sometimes domestic) VCRs. Dwight Cavendish Developments sold equipment to run such systems, including distribution amplifiers, and systems to control large banks of VCRs.[32] The company also promoted a quality control system, to automatically check for faults on the pre-recorded tapes,[33] though it is not clear if this system was ever used widely.[34]

Laser projection TVEdit

One of the most novel DCD products was a colour projection TV system based on multiple laser beams (for red, green, and blue light).[35] The system boasted (for the time) impressive brightness / image size, and also, due to the coherent nature of laser light, did not require focussing. However, the coherent laser beam gave rise to a Speckle pattern in the projected image. This was ameliorated by using a rapidly vibrating screen.

The system was intended for commercial and industrial applications, using 28 kW of electricity, and requiring 4.75 gallons of water per minute for cooling.[36]


This history of the company and its technology has been pieced together from the changes listed in the INPADOC LEGAL status on Espacenet for the following patents:

  • US4613201 Light projection apparatus(Laser TV system; 1982)
  • US6882490 System for protection against copying on magnetic tape recorders (Analogue audio copy protection; 1999)
  • EP1319308 Method and apparatus for processing a video signal for attaining copy protection, a video signal obtained therewith and the use thereof (Analogue video Copy Protection: vertical sync modification; 2000)
  • WO03065716 Anti-copy protection for a video signal (Analogue video Copy Protection: two signal modifications; 2002)
  • EP1926318 An improved method and apparatus for providing an anti-copy video signal (Analogue video Copy Protection: three signal modifications; 2002)
  • WO2004110060 Digital processing disruption systems (Digital video Copy Protection: two or three signal modifications; 2003)
  • US7471479 System for protection against copying on magnetic tape recorders (Analogue audio copy protection; 1999)
  • WO2006040565 Audio copy protection system (Analogue audio copy protection: pulsed signal modification; 2004)
  • WO2007000585 Copy protection method and apparatus (Analogue video copy protection: frequency modification; 2005)
  • WO2009053685 Method and apparatus for generating a security signature (Digital video copy protection: fingerprint generation; 2007)
  • ES2334499 Method for preventing copying if (sic) a programme signal (Analogue video Copy Protection: three signal modifications; 2002 pub 2010)


  1. ^ post by Keith Jack, Sigma Designs
  2. ^ DCS Copy Protection Ltd Homepage
  3. ^ Echostar link to DCS Copy Protection Ltd
  4. ^ DCS Copy Protection Ltd Website 'Technology' section
  5. ^ Archived 28 July 2011 at the Wayback Machine Content Protection - Process Overview - The Walt Disney Studios
  6. ^ "Archived copy" (PDF). Archived from the original (PDF) on 29 September 2011. Retrieved 17 June 2010.CS1 maint: archived copy as title (link)
  7. ^
  8. ^
  9. ^ Content Protection Enabling new choices for consumers - Jim C. Williams, Senior Vice President & Chief Technology Officer, Motion Picture Association of America - slide 8
  10. ^ Archived 28 July 2011 at the Wayback Machine Content Protection - Process Overview - The Walt Disney Studios - page 12
  11. ^ CPCM Compliance Framework, Table 10, Rules for Analogue Consumption
  12. ^[permanent dead link] Secure Video Processor Device Manufacturer License Agreement, section 6, Output Rules
  13. ^ US Patent Application US2010/0064331
  14. ^ US Patent Application 20080263621 - Set top box with transcoding capabilities
  15. ^ UK Companies House search April 2010, Company No. 04667708
  16. ^ ES2334499 on Espacenet (retrieved April 2010)
  17. ^ DCS Copy Protection Ltd
  18. ^ DCS Copy Protection press release about office relocation
  19. ^ UK Companies House search April 2010, Company No. 04145237
  20. ^ Directory Entry for former Dwight Cavendish systems offices in Pasadena, CA
  21. ^ Analog Reconversion Discussion Group Page
  22. ^ CPTWG Home Page
  23. ^ RightsMaster presented to ARDG 2003-10-23
  24. ^ EFF: General Comments on Analog Reconversion Discussion Group
  25. ^ Cruelty to Analog
  26. ^ Status Report from WG9/DVD Forum on Copy Protection System, slide 6
  27. ^ DVD Forum Charter
  28. ^ UK companies House search April 2010, Company No. 01474951
  29. ^ Dwight Cavendish Developments presentation to the Copy Protection Technical Working Group - 20 September 2000
  30. ^ Wireless world, Volume 89 - Page 314, 1983
  31. ^ 10-Q SEC Filing, filed by MACROVISION CORP on 8/15/2001
  32. ^[permanent dead link] Small list of end-of-line Dwight Cavendish equipment from US distributor’s website. Retrieved April2010
  33. ^ BM/E: The magazine of broadcast management/engineering, Volume 25, Part 2, page 70, Mactier Pub. Corp., 1989
  34. ^ "Quality Master:" Dwight Cavendish's Kent Kjellgren on video QC. Tape-Disc Business, 1 December 1997
  35. ^ Electronics, Volume 56, McGraw-Hill Pub. Co., 1983, Page 88
  36. ^ Popular Science, December 1986, Page 20, Laser TV