Fair use or lack of fair play?

I have a column (/var/opinion) in an upcoming issue that deals with my struggles to get a MythTV system working. The column ends with a tease about yet another column on Linux standards. I don't want to spoil either, so I'll leave it at that. However, I have another beef about the way my MythTV system is shaping up, or more accurately, falling apart. I suspect the problem is that our fair use rights are being denied and we are deliberately prevented from capturing high quality content.

First, let me bring you up to date. My television fried, so I replaced it with a great deal on an Samsung HDTV. I have an old TiVo unit that simply doesn't do justice to the new picture quality. So I swapped my old cable box with an HDTV-capable cable box. This particular cable box has a PVR in it, but it stinks. So I figured I'd put together a MythTV system to replace the PVR capability in the cable box.

Here's a point I didn't make clear in the upcoming column, which will probably lead to a number of unfortunate "you dummy" letters:

I'm using a Hauppauge WinTV PVR-500MCE as my TV Tuner card for MythTV. I know that the Hauppauge unit does not do HDTV, and I didn't expect it to. The plan was to tune the Hauppauge card to channel 3 (or just connect to the unit via the AVI or S-Video) and use an IR blaster to make my Scientific Atlanta Explorer 8000HD cable box do the actual channel surfing. I assumed (and I still haven't found out if this assumption is right or wrong) that when I watch regular SDTV, I can set it up to expand the resolution of SDTV to one of the better resolutions of the HDTV. This is, after all, how the cable box itself works.

If I want to watch real HDTV, however, I'll have to change the source at the TV from the PC back to the cable box. I have no problem with that.

Ideally, I'd rather connect the output of the cable box directly to the Linux box, and use that as my source for the PVR. That way I could record both standard and high-resolution content. That's my ultimate goal. The Hauppauge unit was meant to be an intermediate step.

Strangled by cable

Here's the problem. I connected the cable output of the 8000HD to the TV input of the Hauppauge card. I get nothing. Upon more careful examination of the 8000HD manual, I find that the cable box works in two modes. It can output a signal to the DVI connector or the YPbPr cables when you set the unit in HDTV-capable mode, or it can output a signal to the coaxial cable, S-Video, or AVI output cables if you put it in SDTV mode. When you have it in HDTV mode, it shuts off any output to the coaxial cable, S-Video and AVI cables. When you have it in SDTV mode, it shuts off any output to the DVI or YPbPr cables.

In other words, if I leave the cable box in the desired HDTV mode, there's nothing I can do to hook up the cable box to the Hauppauge unit. Even this wouldn't be so bad if I had a one-button switch that flip-flopped the cable box between HDTV and SDTV mode. But that's not how the cable box works. You have to go through a series of contortions to get the box in one mode or the other. You have to turn off the cable box, press two buttons on the front panel and then mess with the remote control to swap modes.

A better way

Okay, so here's what I envision would be an ideal solution, given the absurd restrictions imposed by the cable box. I'd love to buy an HDTV input card (preferably with an MPEG hardware encoder/decoder on it) with an HDMI connector for input and/or a YPbPr+audio input. Assuming I could get Linux drivers for this fictional card (a bold assumption, I admit), this would make it easy for me to turn my Linux box into the ideal HDTV-capable PVR.

As far as I can see, there is no such animal. I can find HDTV tuner cards, but that's not what I'm looking for. I don't want to replace my cable box, particularly because that would limit the number of channels I can receive. I simply want to take the output of the cable box and plug it into my Linux-based PVR.

Something rotten in the state of technology

It is at this point that I begin to smell a rat. Even if I could find a card that has HDMI input, which I can't, I don't think I'd want one. The main purpose of HDMI, as far as I can tell, is to create a standard that supports the ability to block people from making illegal copies of high-quality content.

I don't want to make illegal copies of anything, but I do want to exercise my fair use rights. However, I don't think anyone is going to make a card that permits fair use, because fair use opens the possibility of illegal copying. It amazes me that people are clamoring for HDMI connectors on new equipment when it seems as if the purpose of HDMI is to limit what customers can do.

Regardless, it seems as if the only input card that would allow me to do what I want to do would have to support a YPbPr+audio connection. Maybe I simply missed one in my search, but I couldn't find anything like it. If you know of such a card, please leave a link in comments. Maybe that would settle the issue.

But if no such card exists, that leaves me with some final questions for those of you who may have trodden this territory before me.

Is there really a way to accomplish what I'm seeking to accomplish as my ultimate goal? Can I create my own Linux-box-based PVR that can use the output of a digital HDTV-capable cable box like the Scientific Atlanta Explorer 8000HD, considering the fact that it can only output to DVI or YPbPr plus audio in that mode?

More important, is the brick wall I'm hitting an artificial one? Is it just that PC capture cards haven't caught up to the latest technology (I find that hard to believe, but is it true)? Or is this a situation where legal restraints and special interests have handcuffed companies in order to protect content, even though I should be able to record this content according to fair use? In other words, if the card I'm looking for doesn't exist, what is the real reason it doesn't exist?

Have we really gotten to a point where fair use is being eliminated by legal restrictions on technology? I know this has been the goal of many companies for a long time, but it has been subverted in the past by people who stand up for fair use. Unless I'm missing something, this time it seems to have worked. It looks like there is no such thing as a DVI capture card (or equivalent), and this is the result of the deliberate intention of preventing people from capturing high quality content.


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HD capture / output

BD Productions's picture


there are other options, but that is the least expensive professional card I have found.

Good luck...

Pricey? If more people purchased them, prices could come down... but maybe not enough.


HD capture / edit / output

BD Productions's picture

The card I linked to below is only one of many.

Thanks to HD hardware encoding cards and cheap computer hardware, HD is now in reach of those willing to spend around $2500.00 for a solid HD capture and edit box, add another $6-700 for HD editting software unless you are comfortable in Linux... where there is a free editting solution that is broadcast quality: Cinelerra.

Not wanting to learn about Linux? Next free solution (happens to also work in Linux) is: Jashaka.

Please feel free to Google for either...

- More later,


Paul Archer's picture

A capture card that takes YPbPr as an input isn't available--not because of DRM, but because of the technical issues of encoding a HD video stream in realtime. Think about it: SD is 480p, while HD can go up to 1080p (although 1080i is still much more common). That's over four times the video information. And the data coming out of a YPbPr connection is the raw (decoded) data that the TV needs to display the image, *not* the encoded data that gets sent over the cable or through the air.
In order to capture and compress a signal like that, you'd need a lot of processor power.
If you wanted to capture it, but not encode/compress it, you'd need massive amounts of hard drive space. The raw data from a SD camcorder with firewire output is what, 20GB/HR? So, you could be looking at 80GB an hour for HD.


Anonymous's picture

One possible option could be to use something similar to gnuradio to capture the analogue signals of YPbPr
but it could be tricky in terms of bandwidth feeding into the PC, and the amount of overhead needed to combine the signals digitally and then re-compress

personally I'd be more enclined to look into using a more direct card via pchdtv and then attempting to hack the encrypted signals, assuming this is possible

I'm not sure about America, but over here in the UK HDTV is still something of a shiny new feature
we can pick it up via Satalite (Sky) but not yet via cable (probably sometime around the end of this year)
Once it becomes more common I'm sure someone somewhere will come up with some sort of hardware solution

Signal Source

Lee Parmeter's picture

I have a Samsung DirecTV HD reciever that will output HDTV content via the S-Video port while outputing HDTV via the component output. So, I can record HDTV programming in SDTV resolution using MythTV. However there is no current way to record HDTV programming in native format using cable or satellite boxes. My next project is to build a new MythTV backend/frontend that will connect directly to my Toshiba 50" projection TV via a video to component converter; setting X to 512 non-interlaced format. You can also use the MythTV frontend to play DVD's, music and show family photos.

Been there...done

Anonymous's picture

Been there...done that....can't be done. FCC won't enforce the firewire rule beyond activating it. Apparently it's ok for the cable companies to activate it, then block any programming from going through it. If you want to record any HDTV content, the only way is to record from over the air HDTV signals using the Linux based PCHDTV card to capture using Myth.

A Possible "Start" To A Work Around

Anonymous's picture

Connectivity: Back in the days of the K6 proccessors, when you wanted to add a DVD Drive for playing DVD's, you would use an add-in PCI card. You might even have one of these Hollywood DXR3 cards kicking around, or could find one cheap for testing purposes (at least, that is, until people find out, if this way works). They had very good hardware DVD decoding/proccessing, plus they had a (vga-vga)pass-through for your current video card's output (VGA)to connect to. A DVI to VGA adapter would get you connected into the pass through input port. The output port on the card is obviously VGA. Your HD monitor might have a VGA input, or another adapter for DVI could be used. You wouldn't need a separate/any tuner if you don't mind using only the cable box's tuner. I can't imagine why you would, since you would have direct access to all of the cable box's channels this way. (Linux drivers for these Hollywood DXR3 cards?) http://dxr3.sourceforge.net/ . This might get you past the cartel's intentional hardware lock-out strategy.

Software: The rest would need to be done be done in the PVR software. A lot of possibilities here, depending on the state of the Linux drivers. At worst, you would have to figure out how to use "screen capture" as your video source.

Further: I recall that these DXR3 cards have s-video out, but it won't be usefull to you because it is only accessible by the DVD decoder on the card. You don't need it for your HD monitor anyway.

This is the only way I can think of to get your cable box's available HDTV signal output sources into your PVR box. It's maybe a start. Let us all know if it works, will you?

That won't work. Look at a

Anonymous's picture

That won't work. Look at a DVI cable, the set of pins on one side are analog and the other pack is the digital signal. The TV only puts out digital, a computer video card puts out both. The converter only takes the analog part and puts it out in a vga format, it doesn't convert the digital to analog.


Nicholas Petreley's picture

You're right - you can't do it with a cable adapter. But is there a PCI card (or external device) that converts DVI to VGA? I did a search but didn't find anything.

Apparently No Adapters Available

Anonymous's picture

Checked briefly on google for an adapter that would help you. Nothing. Converting to s-video wouln't be an easy task.

If your not liking the attacks on your fair-use rights, consider stopping the level of cable services you purchase, just short of their criminal act. Saying "oh well", At least I have this or that improved functionality, won't help your cause. Because, they still get paid. If your unwilling to push back, then don't complain.


sledge's picture

My assessment of HDMI is similar to yours. HDMI encorporates High-Bandwidth Digital Content protection. Devices that do not support this (like DVI) will recieve drgraded signal quality from the source to prevent high quality duplication.

This card appears to take the place of your cable STB. However the decoder is software based.

Have you considered calling your provider and requesting a new "Firewire capable" or "IEEE 1394 enabled" HDTV cable box? There was an FCC regulation requiring cable companies to provide a cable box with Firewire to customers who ask.

This will expose the "transport stream" (TS) signal. I know that you can use VLC to transcode, stream, and/or play TS video. It should be possible to integrate VLC into MythTV if it isn't there already. Transport streams are large. Much bigger than their program stream cousins found in the video object (VOB) files on a dvd. But there are currently some ways to work around the limitations you mentioned. Perhaps only until the broadcast flag effort succeeds, however.


Poul Jones's picture

HDMI supports any TV or PC video format, including standard, enhanced, or high-definition video, plus multi-channel digital audio on a single cable. It is independent of the various DTV standards such as ATSC, and DVB (-T,-S,-C), as these are encapsulations of the MPEG movie data streams, which are passed off to a decoder, and output as uncompressed video data on HDMI. HDMI encodes the video data into TMDS for transmission digitally over HDMI.

If the "ways to work around

Curt Howland's picture

If the "ways to work around it" are software based, then there's hope for the future the same way that software decoding of DVDs has helped those of us who own DVDs with different region codes.

I've not heard of the IEEE1394 TS stream before, maybe there's a market here for a hardware-based MPEG encoder that could handle the TS signal in real time?


killerbeesateme's picture

As sledge stated, firewire might be your best bet. However, there are limitation in that system too. The firewire signals have broadcast flags in them (at least comcast's DVR box does) which prevent you from being able to view or capture content. If you do a google search for Comcast DVR firewire, you'll find a few links that kind of give you the lay of the land. everything on the net is mainly for Win XP, but the background of it is still the same.

You probably won't be able to get any movie channels, and possibly other random channels, as they set a flag that will say copy-never. basically a broadcast flag. However, most of your channels should work.

Now, another thing i noticed, was that my processor usage spiked big time when using firewire input. i was at about 70-80% processor usage watching over firewire. Also, you won't get the guide what so ever. Firewire gives you access to the raw channel, and anything the cable box overlays over the incoming channel will not show up. Channel changing takes awhile too.

Hope this helps.


Ken Dryden's picture

FireWire is integrated into Power Macs, iMacs, eMacs, MacBooks, MacBook Pros, and the iPod. FireWire ports were also integrated into many other computer products dating back to the Power Macintosh G3 "Blue & White" computers. All these machines include FireWire ports that operate at up to 400 megabits per second and the latest machines include FireWire ports that support 1394b and operate at up to 800 megabits per second.

Only Standard Channels

Sucellus33's picture

Only the standard channels work through the firewire port. And it sounded like (from the post) that he is trying to get all of the channels to work. Firewire isn't an option at this point.