DVDs and TPMs: how often is CSS used?

On June 2, the Canadian government tabled Bill C-32, its third attempt to implement anti-circumvention laws and other changes to the Copyright Act of Canada. The proposed changes would significantly impact the way Canadians are allowed to interact with copyrighted works stored in digital form, such as movies stored on DVDs. Not much information is available on the DVD situation in particular so there is significant uncertainty as to whether C-32 prohibits DVD backups (as an example):

  • xentac: “with BillC32 can I buy DVDs and rip them…?”; Tony Clement: “So long as no TPM”
  • Drew Wilson: “If you have a home movie recorded on a DVD and you back that movie up…, you’ve broken the anti-circumvention law.”; anonymous commenter: “This isn’t correct. Home movies you burn onto a DVD-R/RW are not CSS encrypted, only commercial DVDs are.”

By “CSS”, the anonymous commenter means Content Scramble System, an optional method of obfuscating the data on DVDs (what some would call DRM). CSS seems to be a “technological protection measure” (TPM) according to C-32 (“any effective technology, device or component that, in the ordinary course of its operation, controls access to a work…”) so I will proceed under this assumption. Hopefully someone closer to the bill can comment on the validity of this assumption.

To provide some clarity to the issue of which DVDs are encumbered by CSS (and thus could not be legally backed up or used for fair dealing under C-32), I analyzed 66 DVDs in my household’s DVD collection to determine if they used CSS. Here are the results:

DVDs encumbered by CSS

(illegal to backup or use for fair dealing under C-32)

Big Six and mini-majors

Title Publisher Year Regions
Gattaca Columbia 1998 1
Monty Python and the Holy Grail Columbia 2001 1
Radio Columbia 2004 1
Reign Over Me Columbia 2007 1 3 4
The Net Columbia 2005 1 2 3 4
The Patriot Columbia 2000 1 2 3 4 5 6 7 8
The Pursuit Of Happyness Columbia 2007 1
Prince Caspian Disney 2008 1
Mr. Holland’s Opus Disney (Hollywood) 1
Good Will Hunting Disney (Miramax) 1998 1
The Boy In The Striped Pajamas Disney (Miramax) 2009 1
The Chorus Disney (Miramax) 1 4
Tsotsi Disney (Miramax) 2006 1
Dead Poets Society Disney (Touchstone) 2006 1
Gone In 60 Seconds Disney (Touchstone) 1 4
Sweet Home Alabama Disney (Touchstone) 1
Catch Me If You Can Dreamworks 2003 1 4
Gladiator Dreamworks 2000 1
The Island Dreamworks 2005 1
The Time Machine Dreamworks 2002 1
Australia Fox 2009 1
Edward Scissorhands Fox 2005 1
Tristan and Isolde Fox 2006 1
The Red Violin Lions Gate 1998 1 2 3 4 5 6 8
Antitrust MGM 2001 1
Hotel Rwanda MGM 2004 1
Raise the Red Lantern MGM 2007 1
Rocky Balboa MGM 2006 1
The Terminator MGM 2004 1
Forrest Gump Paramount 2006 1
Love Story Paramount 2001 1
Rat Race Paramount 2001 1
Sleeper Cell Season 2 Paramount 2007 1 2 3 4 5 6 7
A Beautiful Mind Universal 2002 1
Evan Almighty Universal 2007 1
Ray Universal 2005 1
Schindler’s List Universal 2004 1
The Emperor’s Club Universal 2003 1
The Office Season 3 Universal 2007 1
Die Zauberflote Universal (Decca) 2006 1 2 3 4 5 6 7 8
Chariots of Fire Warner 2005 1 2 3 4
Robin Hood: Prince Of Thieves Warner 1997 1
The Fountainhead Warner 2006 1 2 3 4
The Shawshank Redemption Warner 1999 1
Rome Season 1 Warner (HBO) 2006 1 4

“Independent” studios

Title Publisher Year Regions
Der Freischutz Arthaus Musik 1999 1 2 3 4 5 6 8
Carmen Deutsche Grammophon 2005 1 2 3 4 5 6 7 8
Die Zauberflote by Opernhaus Deutsche Grammophon 2007 1 2 3 4 5 6 7 8
La Boheme Deutsche Grammophon 2005 1 2 3 4 5 6 7 8
Le Nozze Di Figaro by Claus Guth Deutsche Grammophon 2006 1 2 3 4 5 6 7 8
Rigoletto Deutsche Grammophon 2004 1 2 3 4 5 6
Testimony: The Story of Shostakovich Digital Classics 2006 1 2 3 4 5 6 7 8
For the Bible Tells Me So First Run Features 2007 1 2 3 4 5 6 7 8
Aida Opus Arte 2004 1 2 3 4 5 6 7 8
Cosi fan tutte by Glyndebourne Opus Arte 2007 1 2 3 4 5 6 7 8
Die Entfuhrung aus dem Serail TDK 2006 1 2 3 4 5 6 8
L’Elisir d’Amore Virgin Classics 2006 1 2 3 4 5 6

DVDs not encumbered by CSS

(legal to backup or use for fair dealing under C-32)

“Independent” studios

Title Publisher Year Regions
Cardillac BelAir classiques 2007 1 2 3 4 5 6 8
Don Giovanni by Peter Brook BelAir classiques 2006 1 2 3 4 5 6 8
La Traviata BelAir classiques 2007 1 2 3 4 5 6 8
Le Nozze di Figaro by Rene Jacobs BelAir classiques 2006 1 2 3 4 5 6 8
The Genius Club Cloud Ten 1 2 3 4 5 6
Aida Deutsche Grammophon 2000 1 2 3 4 5 6
Klimt Mongrel Media 2006 1
Chopin: Desire for Love MTI Home Video 1 2 3 4 5 6
Chicago Symphony Orchestra Video Artists International 2003 1 2 3 4 5 6


  • Of the 66 DVDs tested, 57 (86.4%) were encumbered with CSS and 9 (13.6%) were CSS-free
  • All of the 45 DVDs from the Big Six and mini-major film studios were encumbered with CSS (they are all illegal to backup or use for fair dealing under C-32)
  • Of the 21 DVDs from “independent” studios (those that don’t appear to be directly linked to a Big Six or mini-major studio), 12 (57.1%) were encumbered with CSS and 9 (42.9%) were CSS-free


The use of CSS in DVDs is very prevalent, especially among the Big Six and mini-major film studios, which made up over 98.23% of the market in 2009 (adding the top 18 figures from Market Share for Each Distributor in 2009). Given this market share figure, the sample of DVDs I used in testing was disproportionately skewed toward toward “independent” studios, and thus had fewer CSS-encumbered DVDs than the average household’s DVD collection would have. I suspect that 98% of the DVDs in an average household’s collection would be encumbered by CSS and therefore would be illegal to backup or use for fair dealing under Bill C-32.

I agree with the anonymous poster who said that home movies are not encumbered by CSS and so they can be backed up legally under C-32. Adding CSS to a DVD is not done by default and is difficult to do, requiring a license from the DVD CCA.


To determine whether a DVD used CSS or not, I wrote the following C program, which I linked with libdvdcss 1.2.10 and ran after inserting each DVD:

#include <dvdcss.h>
#include <stdio.h>

int main(void)
        dvdcss_t dvd;

        dvd = dvdcss_open("/dev/cdrom");
        if (NULL == dvd) {
                printf("cannot open DVDn");
                return 1;

        printf("scrambled (1=yes, 0=no): %dn", dvdcss_is_scrambled(dvd));

        return 0;

I obtained region code information from the debug output of libdvdcss that appeared when I ran the above program.

libdvdcss and Bill C-32

Ironically, downloading libdvdcss would likely become illegal in Canada under C-32 because it states “No person shall…import…any technology…if…the technology, device or component is designed or produced primarily for the purposes of circumventing a technological protection measure” (Section 47 of Bill C-32, proposed Section 41.1(1)(c)(i) of the Copyright Act). This is because the primary purpose of libdvdcss is to circumvent CSS (which I’m assuming is a TPM), even though it can be used for other purposes, such as checking whether a DVD uses CSS or not. I would appreciate clarification on this point from those close to the bill.

It’s important to note that the primary use case for libdvdcss is playing DVDs using free software, such as VLC, not to make illegitimate copies of DVDs. Because the DVD CCA will not provide a license for free software players (because they cannot comply with Section 6.2.4 of the CSS Procedural Specifications, which states “All implementations…shall include features clearly designed to effectively frustrate…attempts to discover decrypted confidential CSS Keys”), people who wish to play CSS-encumbered DVDs with free software must necessarily circumvent the CSS.

A major reason for publishing the above list of DVDs which use CSS is that I couldn’t find an existing online source that provided similar information. Perhaps it is because of the effective ban on libdvdcss in the US due to the DMCA that such information is not more widely available. It is important for those considering new laws to consider these and other unintended consequences of anti-circumvention clauses. The EFF has compiled a detailed list of such unintended consequences of the DMCA: Unintended Consequences: Twelve Years under the DMCA. Perhaps we can learn from the US’ mistakes.

1 Response to “DVDs and TPMs: how often is CSS used?”

  • I have a vhs – dvd burner. When attempting to transfer home movies from less than perfect home movie videotapes recorded with glitches and dropout, this machine has informed me that I am infringing copyright and shuts down. I can get around this by playing the tape later on, past the bad patches, but necessarily I loose some of the filmed image. In the old days if film home movies you could watch the bad bits if they were important enough.

    Is this not a DRM/TPM issue?

    Also, I have had a terrible time trying to burn home movie compilation DVDs. I wanted to make home movies for Christmas gifts a couple of years ago so I went out and bought video editing software called Pinnacle. I destroyed maybe 20 DVDs trying to burn my home movies before researching it. Turned out upgrading wouldn’t have helped at all, since this is a common problem with that software.

    So I went and bought Sony Vegas, which has a better chance of burning a DVD but the DVDs it burns don’t reliably play in all players.

    My assumption is that all these are DRM/TPM problems.

    Am I correct? And if I am, doesn’t that mean that correcting these problems would be illegal under Bill C-32?

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