Buck said:
Digital. No current ambitions for HDTV, but that may come down the pike in a few years.
Okay. Here's the scoop.
Digital signals delivered by:
- encapsulating the video and audio streams in what is known as a MPEG Transport Stream
- the TS is modulated onto an RF carrier signal ... cable happens to use quadrature amplitude modulation i.e. QAM
Digital signals are received by:
- the tuner brings in the RF signal and converts it to an intermediate frequency (IF)
- the TS is then extracted from the IF signal by the process of demodulation (i.e you need a QAM demodulator for cable) ... this process also involves error correction, to try to unsure that the packets the tuner have received accurately describe the original TS
- these first two points above constitute the frontend operations of your receiver. After they have been performed, the signal is sent to the backend of the reciever or to a host processor for decoding of the MPEG TS.
- once the TS is decoded, the signal is appropriately routed to the viewing device
Now, what all that means is this. Your typical analog cards can't work with digital signals (which should be somewhat obvious by the names analog and digital) ... that is, you can't go from your wall straight into the card. They can, however, take a decoded signal outputted by a STB over, say s-video, and then do their stuff (which essentially boils down to ADC into a RGB bit stream) so that you can view the signal on your computer....and, indeed, many people do. Keep in mind, this is only good for standard definition ... you can use a HDTV STB, but the analog out is down res'ed to SDTV (will still look good mind you).
Digial cards are, on the otherhand, obviously able to take the signal off the wire straight from the wall to the card. The problem, however, is that most cable networks encyrpt a large portion of their channel lineups - both SDTV and HDTV. Unfortunatley, this renders the premium content unaccesable by computer cards...you will only be able to access this content through TV via a
rented STB or cablecard with provides provisional access. And before you ask -- no, there is no consumer level computer card that can accept the hugeassmongous uncompressed signal sent over component, dvi or whatever out of the stb (if you have ~3K I can point you to a few prosumer/pro cards..but your going to have to upgrade your system to PCI-X).. ..anyways, you may however be lucky and can use firewire from the stb to a plain old firewire card (ie. no tv capture card required) on the computer though! but encyrption issues (5C) also are a factor here ....
So where was I....what was I looking for? was it a chipmunk? No, no that wasn't it. Was it a squirrel? No, no, that wasn't it either. Was it a capture card? Yeah, yeah, that's what I was looking for!
Anyways, to make this story short, the selection of cards that are capable of working with digital cable is rather a short list currently ... and remember its just unencrypted sources. But as a bonus, there isn't anything dedicated to SDTV only, rather they work for both SDTV and HDTV sources (given the nature of the delivery and rception is identical).
I should also remark that what is recievable (i.e. what is unencrypted) on any given network will vary from caable provider to provider. You'll likely find a bunch of SDTV channels, a few HDTV channels that likely represent the locals that you can recieve OTA, perhaps one or two other HDTV, and its possible that you can also tap into the VOD (video on demand --- by the nature of how its transmitted, its susceptable to allowing you can to see what kind of smut your neighbours have ordered
(note: stb won't, but your card will!) ....you can even watch them pause and rewind! Hillarious)
Now after that whole speel, here's a few cards to consider:
- MIT MyHD MDP-130 ... expensive; hardware MPEG decoder (which is the reason why its $); stable proprietary software; no 3rd party software support in windows; currently not supported in Linux;
- Dvico Fusion 5 (Gold, Lite, USB) ... "software" MPEG decoding cards; proprietary software sucks, but currently only way to watch digital cable in windows (because of MS's stupid BDA driver model); 3rd party software support for OTA sources; both cable and OTA well supported in Linux (except USB model currently); believe OS X would work too
There are a few others too, but I would have to explain why you might not want to consider them just currently ... and I really got to run.....
- Avermedia A180
(currently won't work with cable in Windows
