TiVo/Macrovision DRM seen on IFC shows

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TiVo/Macrovision DRM seen on IFC shows

After a few days of reading near and far about the TiVo/Macrovision DRM flap, I fully believe the response that TiVo has given is true. TiVo says some noisy broadcast video has tripped the flag accidentally, and that it shouldn't occur under normal conditions with cable and satellite connections. However, Aaron Hurley has reported seeing it on a IFC show recorded over cable, and he's posted photos of it on his box:

It's not just local stations. There is a red flag on IFC right this minute. Check it out if you can.

My Tivo is currently recording a conversation with Lauren Bacall and it has the red flag showing up saying that the program will be deleted by 9/23.

You can see evidence here and here
--Aaron Hurley

It could be another bug tripping the flag, but it looks like this might not just be limited to syndicated shows on a Fox station recorded from an antenna connection. I'm curious what caused the bug in this case.

by Matt Haughey September 16, 2005 in TiVo

Comments

Just FYI, this was on Turner Classic Movies not IFC (via Comcast New England in Boston). I mistyped in my original comment.

Posted by: Aaron H at Sep 16, 2005 10:30:04 AM

The red flag I got on the Simpson's episode occurred through an analog Comcast cable. I did not watch the entire episode before it deleted itself, but I don't remember any visual or audible distortion. I can't be certain of the station, but most of my Season Pass Simpson's come from KCBA (a Fox affiliate in the California Monterey Bay Area).

Posted by: seaan at Sep 16, 2005 11:01:32 AM

Others have already posted that Macrovision engineers have "laughed out loud" at the idea of this being caused by noise. The flag isn't a simple bit you flip on an off, it's part of a checksum. Noise is NOT going to properly compute a checksum.

Posted by: Joshua Ochs at Sep 16, 2005 11:15:30 AM

I have Comcast Digital Cable in Boston and TCM is on 213 - clearly in the digital range.

I've been thinking about this and wondering if it is possible that some flag on the channel that the cable company sends to the cable boxes (i.e., Yes, you get this channel) is also read by Tivo and misinterpreted.

Doing a few experiments I've found out that if I record ANY channel that I DON'T get, the Tivo will record with the red flag. So, any time I record the "Call this number to order" channels, Tivo sets it to delete after 7 days.

Could it be that these channels carry/don't carry a required bit of code and that trips the Tivo? Could we have competing info in the video blanking area? If my cable box doesn't get the digital OK to display the channel in time will Tivo decide I have to be DRM'd?

Posted by: Aaron H at Sep 16, 2005 11:51:05 AM

Aaron, that is an interesting diagnostic finding. I suggest you share it with the TiVo people -- maybe try the tivocommunity.com boards.

Joshua, history if full of laughing engineers with egg on their faces. Enough random bits will eventually spoof any code/checksum. Depending on Macrovision's system, and TiVo's implementation, it is possible that enough random bits are being supplied.

Posted by: Bucky the Cat at Sep 16, 2005 12:22:17 PM

And it wasn't MacroVision engineers, it was engineers at a DRM conference - the original post is one of Cory's at BoingBoing. He's editorial slant seems to be trying to stir things up, so I read with a grain of salt. It isn't clear that the people he talked to are familiar with this MacroVision system (MacroVision is an entire family of systems, each different from the others), and they certainly aren't familiar with TiVo's code.

The MacroVision system is a set of flags in the VBI. Now, perhaps there is supposed to be a checksum to confirm the flags to avoid false positives and that's the problem - TiVo isn't doing the calculation right, etc. They admit it is a bug after all.

Posted by: MegaZone at Sep 16, 2005 3:28:36 PM

Ever notice how trivial it is fix the other guy's program, but how difficult if it is the speaker's own program? The armchair engineering speculations that Cory related are half baked.

In security systems, your failure mode is not to allow access. Obviously, the content industry likes that sort of approach. Jim Denney's remarks to CNET imply that Tivo is taking the opposite point of view.

If your DVR code comes across a line 21 VBI extended data field with what appears to be CGMS macrovision data, but data is malformed- eg. the checksum doesn't match, what do you do?

Studio example code no doubt says assume someone tried to muck with the field- lock it down and assume protected.

Permissive school would be to assume it is unprotected until it passed all tests that it was a genuine macrovision flag used by an channel authorized to use it.

Tivo code (from what I could understood Denney's non technical gloss to mean) should be- ignore it if it is not on a known PPV or VOD channel.

It would be helpful if Macrovision simply stated to consumers what they are contractually binding licensee manufacturers to do when these flags or their protections are detected. Further it would be helpful to know what product behavior is not required though strongly recommended.

That way, consumers can make up their own mind if Tivo's DVR behavior makes more sense than Sony's or one from the carriers.

Posted by: Justin Thyme at Sep 16, 2005 4:12:58 PM

Anyone else find it interesting (and by "interesting" I mean "totally irresponsible") that even though the IFC/TCM error was corrected immediately by the original poster, that Matt went ahead and posted IFC anyway? And it was corrected again here, but he hasn't bothered to correct either the headline or the story content? I suppose IFC makes for a better conspiracy story than TCM.

Hey, Matt, I heard a rumor that Tom Rogers killed Kennedy. Now you can post a headline that reads "TiVo's Tom Rogers Killed Kennedy." No, it isn't true, but it will generate a lot of hits for your web site, and that's more important than the truth, isn't it?

Jackass.

Posted by: Bucky the Cat at Sep 17, 2005 8:12:19 AM

I've tripped the Macrovision flag with a DVD Recorder (and no, the source was not copy-protected to begin with). We discover it was because of some white type with a black edge that simulated the levels of Macrovision enough to trip it up. Once we lowered the brightness levels a little, it recorded fine.

Posted by: EjG3 at Sep 17, 2005 12:24:01 PM

I don't buy the "checksumming would prevent false positives" argument for a moment. This is the same kind of information as closed caption data - it lives in the vertical blanking interrupt section of the signal. I've seen numerous examples of noise corrupting closed captioning but retaining valid checksums, and it's not unreasonable to think that actually-corrupt data would pass checksumming for these flags as well. Perhaps Cory's room full of DRM engineers ought to talk to some broadcast engineers in the real world sometime soon. This ain't a secure hash we're talking about here, folks, it's just a checksum, and a not-very-wide one at that.

If TiVo does what I think they're doing, which is to treat a program as having DRM if it sees the right bits set at any point during the recording, or with a very small threshold, that's as many as 54,000 opportunities to get it wrong every half hour, once per frame.

Perhaps TiVo needs to make its implementation a little more robust in terms of avoiding false positives, since they've obviously got a bug. They've got an actual business need for a Macrovision license (as in: they'd be sued out of existence without one, never mind that DVD TiVos couldn't exist at all), though, and Macrovision sets the rules as far as paying attention to these bits go. Since they're a recording device, they *might* even be legally bound to honor Macrovision under the same legislation that mandates it for VCRs.

Justin, while it sounds reasonable to just ignore the bits if you know you're on a non-PPV/non-premium channel, that only works if you're using the internal tuner (which would still be reasonable to do). If you're using an outboard tuner, that'd leave a hole that would almost certainly be unacceptable to Macrovision, i.e. record a show on a "in the clear" channel and just change the external tuner to the protected channel without the TiVo knowing about it (and since most cable boxes don't drop sync on a channel change, there'd be no way for the TiVo to know about it.)

Posted by: Dennis at Sep 17, 2005 9:19:52 PM

"They've got an actual business need for a Macrovision license (as in: they'd be sued out of existence without one, never mind that DVD TiVos couldn't exist at all)"

Perhaps you can explain this a bit more. I don't see why TiVo needs a Macrovision license at all to make standalone DVRs. They could spin off a separate company to make the DVD TiVos, so they wouldn't have to implement MV in *all* their products, and those of us with standalone units wouldn't be victimized by this bug.

Posted by: Mr2001 at Sep 18, 2005 4:07:17 PM

First off, they're a recording device. That alone might make them required to support Macrovision, under the same legislation that forces VCRs to support it, although I suspect that would require a visit to court for any real determination. After all, TiVo was a Macrovision licensee long before the DVD-TiVo combos existed.

Secondly, Macrovision's terms are such that if you need a license, they can and do require that you support their flags on anything you ship. Put a different way, to meet their license requirements that permit them to have the DVD combo units, the standalones have to support it, too. There's nothing to "spin off", either, remember that TiVo doesn't manufacture the DVD units right now, but as the platform vendor they still need the license.

Macrovision is a pretty crafty company (yes, you're free to read that as "pure evil." ;). Not only do they patent their copy protection techniques, they also try to patent as many of the methods that can be used to strip them as they can envision (check out US Patent 6,295,360 for just one example.) Their licensing people are easily as sneaky as, if not more sneaky than, their patent attorneys.

Posted by: Dennis at Sep 18, 2005 5:34:19 PM

I'm quite sure that any of the pvr/dvr mfg'ers would love to be "the iPod of video"... shifting millions of units and racking up profits while the content industry reels under the scourge of digitally enabled piracy.

If Macrovision's technology will prevent the decimation of the movie business that has befallen the music industry, then I'm 100% behind them. Better technology integration with licensees will eliminate these bugs with time.

Without protection from digital enabled piracy, its inevitable that the incentive to invest in expensive entertainment products (movies, music, games) would evaporate. Its already come to pass in music... there are 30 percent *fewer* artists under major label contract today than there were in 1996, resulting in less choice and less diversity to the mainstream consumer, not more. The only rights specifically denoted in the first ratified version of the US Constitution is protection of intellectual property; the amendments known as the Bill of Rights was added years later.

I haven't come across a so-called "fair use advocate" (my term is "copyright hater") whose ever been responsible for exploiting a catalog of creative content to recoup costs or fund, develop and invest in creative works.

Its a pity that the culture of "ripping and trading" music products has been fostered and encouraged by those who wish to achieve disproportionate intermediation in the value chain... building empires on stolen intellectual property.

Posted by: CopyrightFAN at Sep 18, 2005 9:33:53 PM

I called that the cable co.s would roll out there PVRs' in 2001 before anyone knew what I was even talking about. When I heard a cable person confirm there looking into it I knew it was the death of tivo--which is why the stock has done absolutly nothing in years. Of course hollywood is going to weasel in somehow but tivo is not the issue--tivo users are more high tech and will drop it if there are intrusions but the avg schmo who gets a simple PVR from cable co. will put up with it--and the big cable co.s will find ways to control usage and commercialize it somehow. The only recourse will be to have a stand alone DVR that is not networked into the cable and well have to buy filters and hacking programs to take out filters and controls--the other 80% of users will simply submit.
This will all happen by 2008.

Posted by: joben04 at Sep 19, 2005 7:19:22 AM

Dennis:
The idea that theres less diversity because people can share files is sillyness--I would argue the oppisite--I can make "music" and post it to millions of people in about 17 seconds, for free. 10 years ago I would need a record contract and tons of cash.

And as far as movies I love buying a bootleg for 5$ on the street instead of paying $10 in the theatre (with the $20 popcorn). The studios are doing much of the movies on a PC and prob. are making alot more $ on them--I have no sympathy for them, or the music industry.

Posted by: joben04 at Sep 19, 2005 7:28:00 AM

joben84 -- I don't think it was my post you were reading when you replied.

I'm not a fan of DRM myself, but neither am I a "copyright hater". I'm more than happy to pay a reasonable cost for my music and movies, and if I think the cost is unreasonable I simply go without. I'm a commercial software developer, and my works rely on copyright just as much as a movie does. That said, once I've purchased a movie, I also think it's perfectly reasonable that I could copy that movie onto my home media server so I can watch it where and when I choose to, or to record a show and keep it around until I get around to watching it.

I do understand why TiVo did this, and the content to which it is supposed to apply, though, and am not overly concerned by it, assuming they fix the issue with false positives. I don't buy "slippery slope" arguments in general.

Posted by: Dennis at Sep 19, 2005 12:50:22 PM

CopyrightFAN:

The idea that the music industry has been "decimated" is simply ridiculous. There may be 30% fewer artists under major label contract, but there are more artists overall - they're just signing with smaller labels or going directly to consumers. And despite having fewer releases, the major labels are still making more money per release, at least according to the last figures I saw (which admittedly are a few years old).

Finally, as long as you're citing the Constitution, remember that it says "for limited times". I don't think the founding fathers imagined that copyright terms would be extended every couple decades in order to prevent Steamboat Willie from entering the public domain, or that computer software would be protected by copyright for so long that by the time it enters the public domain, the only computers that can run it will be in museums.

Dennis:

I don't think TiVo needs a Macrovision license at all, and you don't need to go to court to see why. The only law that mandates Macrovision is the DMCA (see subsection (k) at http://www4.law.cornell.edu/uscode/html/uscode17/usc_sec_17_00001201----000-.html), and it specifically refers to VCRs: VHS, 8mm, and Beta "analog video cassette recorders".

Posted by: Mr2001 at Sep 19, 2005 9:01:45 PM

Mr2001:

The legal issue is only part of the problem (and although I forget the specific legislation, the Macrovision requirement predates the DMCA -- VCRs were mandated to recognize it long before DMCA.) In any case, if Macrovision is seen as a copy control technology, the DMCA would still applicable if a TiVo is seen as a circumventing technology.

Even taking a legal requirement to incorporate Macrovision out of the picture, TiVo has a product line to ship, and third-party licensees of their own to support, that requires that they have a Macrovision licence (having a DVD license means having a CSS license which means having a Macrovision license.)

TiVo, and other DVR manufacturers (note that at least one ATI capture card user also got hit by this same issue, as noted above,) really don't have much choice. Even if you make the assumption that they aren't strictly required to do this, would it be prudent from a business standpoint to open themselves up to possible lawsuits? Why are the complaint about this not being leveled more appropriately, at your local congresscritter?

Posted by: Dennis at Sep 20, 2005 6:53:29 AM

I am surprised that the title of this story still hasn't been corrected. The problem occured on TCM not IFC.

Posted by: riffola at Sep 20, 2005 5:39:50 PM

Tivo made a bad business decision in their chosen implementation of this technology. They should never have agreed to the new Macrovision license, since it is so restrictive. They should have said, well gee, we'd like to help you out but our users need to be able to use their Tivo boxes in the way they were intended, without broadcaster interference.

http://mrshiney.froppy.com/blog/

Posted by: Mr. Shiney at Sep 22, 2005 8:20:12 AM

Reading the various DRM postings really saddens me. We can debate and rationalize TiVo's decision to implement DRM all we want, but to me it comes down to a single very simple issue: When I bought my first TiVo the slogan was 'TV your way'. It's not TV my way anymore - it's TV their way, which to me ultimately means the death of TiVo. Very sad indeed.

Posted by: JR at Sep 22, 2005 3:45:11 PM

They wouldn't add this feature if they didn't plan to use it. Simple. Digital Restrictions Management (DRM) is right around the corner.

Posted by: CH at Sep 22, 2005 7:14:23 PM

I love my TiVo Series 1 - but no longer evangelize TiVo...I haven't changed - TiVo has (to an anti-Macintosh, DRM encumbered ech). My series 1 does what I want - DRM restrictions are coming...Foolish to think otherwise.

Posted by: KevinH at Sep 23, 2005 7:37:16 AM

Although I haven't had this issue with my Tivo, it does remind me of the issues I've had with a new DVD-recorder.

It's a unit with a DVD-RAM disk, and in theory, I should be able to time-shift HBO and Cinemax programming, but am prevented from making a copy to share with someone else. Not a big issue for me.

But the reality is that I am unable to record any HBO/Cinemax programming. The cable company and HBO blame the DVD Recorder manufacturer, although I know for a fact it's an issue that isn't just limited to this particular machine.

This is my problem with DRM schemes. It isn't the idea of copyright protection, it's the practical experience that DRM prevents authorized use. And when it doesn't work correctly, the attitude is "Hey, it's not our problem."

Posted by: Rick Ellis at Sep 23, 2005 9:51:22 AM

I'd have to agree--DRM has to be on the agenda. Todd Lokken.

Posted by: Todd Lokken at Sep 24, 2005 7:59:09 PM

This is not a mistake. If there's that much noise on the line, the video signal would have been obviously affected. For months, those who provide cable operators with the equipment for their business (set-top boxes, headends, Etc.) have been preparing products to secure the digital content. The cable operators and content provides (movie studios), not the consumer, will determine what can be recorded and on what media what can stay on recorded media and how long. HDTV-DVR will be no different. Even units with DVD burners will have downloadable firmware that will require digital signatures.

Posted by: InTheKnow at Sep 25, 2005 7:01:10 PM

Just wondering if a cable filter (with the technical features stated from this site, http://www.hdfilters.com) is installed in your box while recording the show, can Fox still detect such recording and cut the show? Just curious here.

Posted by: Youngblood at May 24, 2006 8:13:36 AM

TiVo/Macrovision DRM seen on IFC shows

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