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HDTV PC Capture Solutions?
Posted by
Cliff
on Thu Nov 18, 2004 10:09 AM
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?"
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Chances are... (Score:2, Informative)
Never mind about the chip (Score:2)
One word (Score:5, Funny)
Bah (Score:5, Insightful)
I was surprised to discover that, as of 7PM CST, last night's show (which would not be seen here for another hour) had been posted 11 hours earlier, most likely from an HD capture in euroupe. So, I got both shows. While I was at it I also grabbed the last couple Enterprise eps (620x320-ish avi), but I'm sure everyone here already knows about those.
If I had been on a "real" computer instead of my underpowered laptop, I could have watched last night's west wing (hi-def cap, but 480x480 svcd) an hour before it even aired in the US. I thought about getting a tuner, too - but why bother to do it myself when I can get it from someone else even quicker?
Parent
Cable (Score:5, Informative)
It's $3 more a month than the normal DVR Time Warner offers.
I know this might not be an option for you, but others might want to know that HD DVRs might just be $36/yr. away from them.
Re:Cable (Score:4, Informative)
Also, when you're renting a box from your cable provider, they expect it to be returned in the same condition when you cancel your service. Hardly a hacker-friendly policy.
If you want some basic (but flaky) recording capabilities without the hassle of a VCR, get the Time Warner-offered box. If you want reliability, flexibility, and the ability to hack it, I think you're SOL for now.
Parent
SA8300HD box not buggy (Score:3, Informative)
As someone who works at Time Warner Cable, I can tell you exactly what the problem is. You have a poor signal going to the box. If your Tuner level is -10 dbmv or below (along with poor FDC and RCD signals), the box will not be able to lock onto that channel properly. Sometimes, it may have a good enough signal at the start of the recording but t
Re:SA8300HD box not buggy (Score:3, Informative)
It's basic rule of thumb with any service based industry. We will not confont you with an issue you *might* be having. If you do
Re:Cable (Score:4, Insightful)
I know this might not be an option for you, but others might want to know that HD DVRs might just be $36/yr. away from them."
which is fine, if you like a buggy crashy DVR with a lousy interface and being locked out of doing anythign with the recorded programming. =)
e.
Parent
In the same boat (Score:3, Interesting)
The way I understand it, DVI is encrypted, so your odds of finding anything in that regard are very low. Composit seems to be your best chance, but as of yet, I havent seen an affordable video capture card.
ATI however, does make a HDTV card, but the problem with it is it only does broadcast free to air type HD, which is basically non existant in my area. If you are in New York, or a similar area, it may be feasible. The ATI card was about 400$ 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.
RE: In the same boat (Score:4, Informative)
Just FYI, you can find a listing of HDTV broadcast stations in your area with: CheckHD [checkhd.com]
Parent
Scan converters (Score:3, Informative)
Since free-to-air decoders are all we're likely to see for awhile, it's probably best to offload decryption to your set-top receiver.
Therefore, even though pcHDTV has no more stock of the HD-3000 [pchdtv.com], and none are available on eBay, it's worth exploring. HDTV input support may be limited to RF, but one can circumvent this problem with nominal quality loss by us
Your Only Hope... (Score:4, Interesting)
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.
Re:Your Only Hope... (Score:3, Informative)
Throw in the fact the ATI HDTV doesn't play well with any other cards except ATI, well they can keep it windoze only. =)
ATI Video Cards: Newsflash (Score:3, Interesting)
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
Bandwidth. (Score:5, Informative)
Re:Bandwidth. (Score:3, Interesting)
Not true. DVS [www.dvs.de] 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 [isi.edu] on Linux... The capture card isn't the expensive part :-(
Re:Bandwidth. (Score:3, Informative)
The video signal commonly referred to as "component" and having the 3 RCA connectors (Y,Pb,Pr) is analog, not digital. I can't tell you how many people are confused about this. (: Other than bandwidth and timing formats, it's not that much different than S-video, which is also a type of component signal and is sometimes written as (Y,Pb+Pr) or (Y,C).
So if yo
Was on /. before (Score:2, Informative)
Samsung SIR-T165 (Score:5, Informative)
I've hooked it up to my Mac, with a piece of sofware called VirtualDVHS and captured HD streams off of the device.
HD Streams gobble disk space like you wouldn't believe.
I think they may even have made a model that does satellite feeds also, with firewire ports, but you'd have to check around, and maybe hit ebay.
ATI has a HDTV card !!! (Score:2, Informative)
Not anytime soon (Score:5, Informative)
Fortunately, HDTV is broadcast as a MPEG2 stream to begin with (with additional error correction). So you can get a tuner card that simply saves the raw data that is broadcast. This works great for over-the-air signals. For satellite and cable, you need to get to the signal after it's been unencrypted, but before it's been decoded. Your two options are to use a decoder with firewire output, or to put your recorder into the decoder box (like TiVo does).
Re:Not anytime soon (Score:5, Informative)
Regular analog TV, whether broadcast NTSC/PAL/SECAM, older analog cable (for me, channels under 100), or regular VHS tapes, is a signal that is essentially fed directly to the electron beam in your traditional TV. There is some funky electronics magic going on, but essentially, each dot in each frame corresponds to a specific fraction of a millisecond of the signal. (Some analog cable channels are scrambled, and decoder boxes will correct the mangled signal. There was a project, fscktv, to do this with a video card, but I never saw it actually work.)
To record an analog signal, you have two important steps. First, you need a TV tuner card that digitizes the signal. Second, you need to compress the video into something managable, such as MPEG-2. The PVR-250 cards are popular because they do both steps.
Digital broadcast TV is simpler. You just need to extract the digital information from the broadcast, much like a modem gets the digital information encoded on a voice phone line. With digital broadcasts, the process of compressing the data is done by the broadcaster, so you don't need any extra work to get a MPEG-2 stream.
Satellite and digital cable, whether HDTV or regular resolution, are sent as MPEG-2 streams, but the problem is that they are selling access to the channels, so they usually encrypt the streams. They assume you'll use their decoder boxes that do two things. First, they unencrypt the stream. Then they decode the stream. By "decode," I mean play the MPEG stream. That means you're back to an analog signal, whether you're using composite, s-video, or component outputs. Even if you use DVI or HDMI, which are digital, it's a decoded signal, not the MPEG stream.
So to record digital cable or satellite broadcasts, you have to either re-encode the signal, which simply isn't feasible right now for HDTV, or you have to somehow get the signal before it's decoded. If your PVR is integrated with your cable or satellite box, it can get the original MPEG stream (which is how DirectTiVo works). The only other option is that some digital cable and satellite boxes have a firewire port that you can connect to your computer, where they send the MPEG stream. MythTV doesn't support that yet, but someone was working on it a while ago.
In theory, you can get a smart card from your cable company that plugs into devices with digital tuners, which allows them to unencrypt channels that you are subscribed to. Some of the more expensive HDTVs accept them so you can use them without a cable box. There's nothing really stopping someone from building a card for your computer that uses the same card.
Parent
My research (Score:5, Informative)
From my research, specifically, into HDTV, I discovered that all the cards only will decipher over the air (yes, with an antenna) HDTV signals and not HDTV from a cable or satelite provider. Highly disappointing. While I do live in the NYC area, I could have gotten an antenna and received NBC, CBS, ABC and Fox all in HDTV over the air, I could not receive HBO, Discovery HD, etc. Because of this current limitation, I temporarily gave up on the HTPC and am waiting for more reasonable resources.
Oh, and something else I found, the FCC has declared that all cable providers MUST have firewire interfaces on their decoder devices as of May 2004. This would mean you could connect a PC to your cable HD converter in order to record programs, but it does not mean that once the programs are on your PC, you will be able to access them from anything other than your cable box.
Re:My research (Score:3, Informative)
This website, Digital Connection [digitalconnection.com], provides much, much information regarding HDTC and HTPC. In fact, I see they have a which *may* work to decode HDTV signals from cable providers, however at the bottom of the page it says, "QAM decoding is under development due to the variations in Cable service providers. QAM256 generally has been reported to work, although QAM64 still poses problems with the decoding software. FusionHDTV QAM decoding is limited to only the non-encrypted chann [digitalconnection.com]
sorry... here's what i got (Score:4, Informative)
There's the firewire pull content/control from the hdtv box. The mac folks seem to have the easiest time with this...
There's OTA terrestial DTV cards (like the linux hdtv card mentioned, and ati's HDTV wonder)
There's a QAM capable card out there Fusion III QAM HDTV Tuner Card(no idea on linux drivers), but that's only useful if your cable company does NOT encrypt their QAM signal...
Ideally, IMHO... we need some sort of PCI CableCard docking device, but I doubt our content controlling masters will allow that. Although, the more CableCard ready HDTV sets I see, gives me hope that someone will take the chocolate and peanutbutter and come up with PC HDTV PVR reeces peanut butter cups...
a PCI card that was CableCard ready would allow legitimate digital cable subscribers to watch digital cable on their PC/etc.
You can get HD PBS for free with FTA DBA satellite cards.
e.
Uh, no. Sorry. (Score:5, Informative)
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.
There are only two close-to-usable solutions so far: IEEE-1394 keeps it's delivery from device to device as the compressed transport stream. The problem being that most transport streams from these devices are encrypted. Some aren't. You might get lucky. The other is to find a tuner tuner card that can decode the QAM signals that cable companies use. The problem being again, that most cable companies encrypt those signals (at least those you can't get over-the-air anyhow).
Check back in about five years.
Re:$2000 cable box? (Score:3, Informative)
DRM.
acronymonious much? (Score:5, Funny)
but then again , everybody knows that
STFU (Score:3, Funny)
Not cheap? (Score:3, Insightful)
Comcast DVR (Score:5, Interesting)
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.
Re:Comcast DVR (Score:5, Informative)
Now, if only I had a MPEG transport stream player that doesn't disrupt audio that VLC player does on my PowerMac..
Parent
RF...? (Score:3, Informative)
At first sounds like someone recording a symphony for an eventual release on SACD but then using their mom's answering machine to record the concert.
I looked into it a bit more. [pchdtv.com] The RF is actually a coaxial input. Which means it's the same exact input you'd get from, say, Comcast [comcast.com] or your local cable provider. I don't have time to do a lot of research but isn't this what you're looking for? Is there something I'm missing?
Re:RF...? (Score:3, Informative)
Yes, QAM decoding capabilities. The PCHDTV only decodes raw OTA HD broadcasts, and that's what it assumes is on the coax input. Unfortunately, the raw cable signals sent by cable companies over their coax use QAM encoding, as well as encryption for premium channels. And none of the digital HD cable boxes they give you output an OTA-style signal, they output DVI, component or something similar (which is, I guess, uncompressed HD video).
So in short, your method doesn't wor
FusionHDTV? (Score:5, Informative)
Pros:
- Supports OTA ATSC, as well as some support for QAM64 and QAM256 (unencrypted only).
- No broadcast flag hoops to jump through.
- Recorded DTV programming is saved directly to disk as non-DRM'd MPEG-2 TP files (with full AC3 audio) that are easily converted to MPEG-2 PS format.
- Recorded NTSC (analog) programming is saved in MPEG-2 PS that could be transcoded easily for DVD.
- Image captures are saved as TIFF at full
resolution.
- Cheap: ~$150
Caveats:
- Output is only via your video card (overlay). Works with DVI, but tweaking video card resolutions to those that "HDTV-ready" televisions like might be a pain.
- Only RF inputs, no component/DVI
- No Linux support that I'm aware of
- Works best with ATi RADEON-based video cards (can offload more CPU work)
- The recording scheduler is buggy--like first year compsci student buggy.
- Slow tech support response
- Haven't tried using it with any of the popular HTPC apps yet
- Needs a decently-strong HD signal (18db+), a Radio Shack amplifier
there is an OS X solution..... (Score:4, Interesting)
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.
A CableCard-based TV card is what you need (Score:4, Interesting)
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
Cable HDTV - QAM Encoded (Score:5, Informative)
webcam (Score:3, Funny)
(Seriously though, if you had multiple webcams aimed at different parts of the screen, and software to reintegrate the video streams... let's see them DRM that!)
What my current solution is (Score:3, Interesting)
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
Re:how about (Score:2)
One RF TV antenna coaxal reception port
Also, the FAQ (which isn't quite up to date) mentions that it will ONLY work for terrestrial broadcasts, and that it's ONLY antenna.
Re:how about (Score:4, Informative)
There seems to be some good information here [byopvr.com]. Ignore the "DVIco FusionHDTV DVB-T Digital TV Tuner Card"; it's composite and SVHS input only. The MyHD MPD-120 Tuner [byopvr.com] (actual MPD-120 mfg. product link here [mitinc.co.kr]) has a DVI-in daughterboard, which is nice (though it doesn't have QAM decoding, apparently). It also outputs IEEE1394, but under Windows XP only, which sucks. But it does have component video analog output. So that might be useful, but doesn't seem to be the holy grail.
Parent
Nothing for under $25,000 (Score:3, Informative)
I have a game company client who needed to be able to do real-time screen caps of game play at HD. What we did was have them do a VGA output at 1280x720 60 fps. We then ran that through a converter box to take the RGB VGA to a component digital HD-SDI signal. That wen
Re:how about (Score:3, Funny)
Re:Sorry... (Score:5, Interesting)
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?
Parent
Re:Sorry... (Score:3)
Have one wire to each device. There's no reason I should have to worry about whether the VCR is before or after the digital cable tuner... or before or after the DVD player... or should be choosing channels with one remote, playing DVDs with another, and controlling volume with a third. Universal remotes are a bad hack... they either don'
Re:Sorry... (Score:4, Insightful)
I hate to be a "Me Too" voice, but...
So, for various and assorted reasons, I have had to recently re-purchase the following items:
And I still had my 5.1 receiver.
Between all the weirdness hooking everything up, and then configuring EACH unit, I must have spent a good 4 to 6 hours beating on this system to get it to work (Not to mention that my receiver forgot it had all 6 speakers, and needed to be reconfigured as well!)
The AV Guys (TV/HDTV/DVD/Game Console makers) ALL need to come up with some sort of intelligent daisy chaining scheme. I mean, really, SCSI has worked for years, why can't they get it together for AV equipment. They can put a little push-button on the back of the equipment to select a priority number, and then when I decide to play on the GameCube, it would just automatically override whatever else I was watching, without having to make me select which stupid input I want.
Really, having a printout on the side of my TV to remind me which TV input to use for each device is just silly, and is one of many reasons why grandma and grandpa won't spend money on any of these new gadgets.
Parent
Re:pchdtv (Score:3, Informative)
the pchdtv card only supports RF input (which only works with over-the-air broadcasts). The guy wants to be able to record Dish & Cable HDTV, which you can't do with the PCHDTV card.
T
Re:Acronyms! (Score:3, Informative)
Most satellite and digital cable systems are considered this.
DVI = Digital Video Interface
It's that new connector with lots of really small pins that connects monitors and HDTVs together digitally.
DVR = Digital Video Recorder
TiVo, ReplayTV, New cable/satellite boxes with built in hard drives, etc.
HD = High Definition
The new TV standard. 4x the resolution. Roughly 16x the color depth.
HDTV = High Definition Television
See above.
OTA = Over The Air
Sucked in with an antenn