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HDTV PC Capture Solutions?
Akai asks: "With HDTV DVR's costing upwards of a thousand US dollars or more, I was looking for a HiDef capture card that would work with Linux and an external HD receiver.
The pchdtv card looks nice but it's RF input only for HiDef content, and only supports OTA at this point.
Both DirecTV and DishNetwork HD STBs can be hacked with FireWire ports, but it's not cheap, so I was trying to find a capture card with either DVI or Component inputs, or a converter to take either of those to FireWire. The old Dish Network model 5000 receivers had an option to output HDTV RF but they are no longer compatible with Dish's current HDTV broadcasts.
Google has not been helpful in this regard, and all I've found is professional (>$2000US) format conversion gear.
Is there a PC (hopefully Linux) based video capture solution that can capture the output of a cable of DBS STB (RGBA, DVI, or Component out) without a significant loss of image fidelity?"
I have been asking the exact same question... without much luck
The way I understand it, DVI is encrypted, so your odds of finding anything in that regard are very low. Composit seems to be your best chance, but as of yet, I havent seen an affordable video capture card.
ATI however, does make a HDTV card, but the problem with it is it only does broadcast free to air type HD, which is basically non existant in my area. If you are in New York, or a similar area, it may be feasible. The ATI card was about 400$ and included an antenna.
Other then that, I think your SOL. Expressvu, rumour has it, is coming out with a 600 HDTV/PVR next year, but Ill believe it when I see it. Also, due to storage requirements, it will only record something in the neighbourhood of 8 hours at HD resolutions.
That's a cheap, well-built solution that would suit your needs. Linux users really need to try harder to force ATI to create a small team for creating these drivers.
Here's an idle thought I had. Probably more effort than it's worth, but an interesting exercise...
Devise a circuit to take a 720p component signal, and convert it to 4 s-video feeds, one for each quadrant of the raster (top-left, top-right, bottom-left, bottom-right).
Feed these to 4 standard def mpeg2 capture cards (PVR250, etc.).
Do some mpeg processing magic to combine the 4 captures into one stream, handling frame synchronization and sound from one of the cards.
I have NO idea if such a circuit is possible, and I don't know enough about mpeg2 to even suggest potential algorithms.
I'll let those with a little more clue dismiss the idea or generate their own little light bulbs and start a project...
Steve (CoffeeBreath!)
-- If you don't understand it, blame it!
I agree.
But I would also like to point out that there is a *huge* market for a "wife proof" AV solution.
Of course, when I say "wife proof", I mean "non techie" proof. The former certainly isn't politically correct. I realize that. However, in my case, it is what I'm seeking.
Basically, the whole concept of multiple sources and multiple remotes has failed miserably. It is too wonderfully complicated. We shouldn't require a flow chart to operate the AV equipment. Here's what we need:
1) A communication method for devices that does not rely on line of sight. My programmable Sony IR remote works great except for those cases when the sun is setting and interrupts a portion of a macro, etc. Then the whole system needs a technician.
2) Discrete on and off codes for this system. See problem #1.
3) No more AV component switching. Just daisy chain all the damn stuff and give each device a priority. If I want to watch a DVD, then I turn on the DVD player which has priority over television content. All devices recognize this priority and do their own switching accordingly. Additionally, a single box that does everything (TV, PVR, DVD and Media) would simplify greatly. I'm open for realistic alternatives.
4) A friggin' industry standard. If everyone wasn't trying to make a buck for themselves, we'd be light years ahead.
What am I missing here?
Life is the leading cause of death in America.
The new Comcast DVR (Motorola 6208) allows capturing
of the HDTV stream through FireWire. It's a little tricky to get it working. I needed to patch libavc1394 to recognize the device correctly. Once that works you just need to send it a signal to start sending the stream (dvcont record) and then you can capture it with ddr1394. The Comcast DVR is $9.99 a month here, so that's a cheap way of capturing HDTV.
i don't know if it was based on anything else, but on some Mac site i read about a piece of software that used the firewire output on the back of digital cable boxes. you just connected it to your machine with a normal firewire cable and the software could capture HDTV. supposedly if you have digital cable and your box does not have a FW port you can demand one (some FCC rule because some HDTV ready TVs have firewire inputs?). it seems only the HDTV channels would come through the port though, so on my system that's maybe a dozen channels if you had the full subscription package.
i realize you wanted a linux solution, but if there is this OS X solution that require no additional hardware, and some shareware software... maybe there is a Linux version? or could be? sorry i forget where i saw it and the name, i just stumbled across it a few months back. i dont have FW cable box and i am awaiting the PVR cable boxes to upgrade so i'll cope till then.
Not true. DVS sell capture cards for uncompressed HDTV, which work with standard PCI slots and give you the raw video signal (at just over 1 gigabit per second). Not cheap - we paid $16k for ours, although they've gone down since then - but definitely possible.
We use it for uncompressed HDTV video conferencing on Linux... The capture card isn't the expensive part :-(
You can't record uncompressed HDTV signals on your PC without a really muscular hardware-based encoding system. The raw, uncompressed signal is too much bandwidth to put to disc and I'm unaware of any consumer-level MPEG chips capable of real-time encoding of an HD stream.
.5-.75 real time encoding to MPEG. You can do it faster, but the quality sux0rs. And yes, there are pro boards that can do this, but for $$$$ and they're *only* real-time, not multiples of real time.
The solution would be a CableCard based TV card. CavbleCard is the new standard for enabling digital/HD/premium cable tuning capabilities directly in TVs and other devices. Basically you get a smart card from the cable company that fits a slot in the device, providing the authentication and decoding capabilities otherwise provided by a cable box. You still can't do interactive stuff like PPV and some of the stop/start movie functions, but for HBO and digital tier channels you can finally ditch the cable box.
With a CableCard based TV card, you'd be able to do what DirecTivo and cable-provided DVRs do -- take the *pre-compressed* signal off the cable line and write it to disc. No encoding required, no encoding hardware required. Playing these files just means pumping the data through the tuner portion of the card as if you were watching a live stream.
The challenges for most would be (A) will they authorize CableCard for PC-based DVR setups and (B) would there be any easy way to transcode the files to open standards? My guess is "maybe" for (A) and "unlikely" for (B). I'd wager that "they" really, really don't want people getting even well-encrypted/encoded HD video on their hard disks.
Slightly off topic: Why aren't there inexpensive real-time or faster MPEG encode/transcode boards for the PC? There are so many DVD recorders that use hardware encoding setups these days, that it would seem trivial to provide a hardware MPEG trans/encoding setup for PCs for a couple of hundred dollars. I hate spending
I have a DVR/HDTV cable box from Comcast. It has a firewire out.
I am able to send the MPEG2 Transport Stream down to my OS X machine via a couple of tools available on OS X (AVCBrowser, etc.), and then open it directly using VLC, and show it on my cinema display. Pretty neat stuff! I watched a recent Patriots game in HDTV with some friends this way.
That stream eats gigs of HD space fast, though!
And it's most definitely not "wife-proof"... yet
Um, guys? those BT shows marked HD aren't true HD, or at least not the level of HD that was broadcast (1080i for most, 720p for some) most BT shows are 480i, *SOME* might be 480p, but that can be argued if it's HD or not. Basically, if your download is less then a gig for an hour, it aint HD. There are *SOME* HD offerings, but those are fairly large, and won't play on an Xbox ;-)
Watch one of these downloaded shows, then turn on the HD version of the show, if you can't tell a difference, you're fairly blind, or don't have a High Def compat. tv.
The question was how could he record HDTV without losing quality. This is losing quality. It's nice to not have ads, but it's FAR from HD.
Heck ATI still doesn't have an acceptable Windows driver for that product.
We are the 198 proof..
"The satellite/cable box then decodes that stream to produce the full HDTV-resolution signal, that gets delivered to your monitor (either via analog component or digital DVI/HDMI).
That full-resolution bandwidth required to re-digitize/re-encode the full bandwidth signal to a recordable transport stream is currently beyond the capabilities of any pc-based solution under that $2000 price-point."
If the "satellite/cable box" can decode it, and doesn't cost $2000 why isnt there a card that can do the same thing?
Heck ATI still doesn't have an acceptable Windows driver for that product.
Newsflash: ATI doesn't have an acceptable Windows driver for *any* product.
How many times have you had ATI software lock up a machine? I've even had it trash partition tables on crash.
Absolute garbage. Even though the hardware is good quality and theoretically does what I need, the cards are useless.
At the very least, they should be open-sourcing drivers for obsolete products.
Don't ask me about the time I installed over 150 ATI AIW Pros at a Toronto TV station... then had *no end* to the problems when Windows 2000 came out and they wanted to upgrade a year later.
Unless they start to take their responsibilities to produce working (and free of silly UI "embellishments" which makes ATI's MultiMedia Center look like it was designed by a 14-year-old anime fan with Downs Syndrome) software for their hardware, their hardware shall remain utterly useless, and I shall continue to warn people away from it.
Fire and Meat. Yummy.