TV Tuners on GNU/Linux

[rod]

Here is a quick response to the first post:

> Initially, I'd like to be able to watch and record shows over TWC from my
desktop

>recommendations or experience with a well-supported TV Tuner card on the
more >popular GNU/Linux.



Google PCHDTV



> Can I pretty much pick from any of the newer Hauppauge  hardware?

>Likely yes, I would recommend checking to see what chip is used in any card
you plan >to buy and see what you can find out about its Linux support



>I understand that to decode most HDTV I'd probably need a cable

>receiver feeding into the tuner.



Yes, this is true for receiving the content that TWC has to sell you.  See
below for a greatly simplified over-the-air option as a first step.



>That's not a huge deal, but would obviously be better without it.

I would recommend getting started without the complications of a cable box.


>I'd like to be able to watch and record at the same time (I think), so I'd
either
>need two cards or a dual tuner, right?

In general yes, this is correct.  (I have a more complicated answer that
only applies in limited cases that I won’t bore you with.)







Response to later posts and my musings:



Nowadays I think video capture might be considered a sub-function of most TV
tuner cards.  I could be wrong but I think there used to be devices that
would capture the images that were being sent out the PC’s video.   All of
my TV tuner cards, both older analog and newer digital cards, have plugs
that could digitize composite (yellow plug) tv signal and some of my tuner
cards have s-video (round plug) input plugs.  Both of these additional
signals are analog, I don’t know of any tuner cards that also have digital
composite (red, green, blue plug) capture.  Composite is a much better
digital signal.



I've had a Linux PC setup as a personal video recoders (PVR) for several
years now.  However, all of my experience has been with over-the-air (OTA)
content.  Recently I did have Surewest cable for a two months but I never
tried to integrate content from their cable box into my PC based PVR.  I use
MythTV to control my PVR.



After 18-24 mo. of having a stable analog system Jim Manly (UncleJim) and I
both ordered and started working with digital tuner cards sold by PCHDTV.  We
both got model 3000 cards.  Since then Jim has added a model 5000, I have
moved on to a different tuner device.  We used PCHDTV because there cards
were specifically advertised to work with Linux.   I still have my model
3000 you are welcome to experiment with it.





As for capturing a signal from the cable company I think you would have
several options.   I’ll assume there is no Linux solution that incorporates
any “cableCARD” implementation that TWC may use.    Pardon me if the
following is overly simplified, I’ve recently been thinking about this
problem and this is as much of a recap for myself as it is a specific answer
to your question(s).   So just working from the back panel of a TWC digital
set-top box (STB) you might have the following output options:



--Wire-fire  this seems like it would be a great interface for transferring
info back and forth from STB to PC.  I don’t know that TWC publishes any
info on how to communicate with their STB via this interface.



--HDMI will have all the digital video and audio signal contained within one
simple wire and connection.  Unfortunately I know of no PC hardware that can
capture signal from HDMI.



--Antenna (co-axial cable) pass thru to a PC tuner card.  For this setup I
think you get a tuner card similar to the one mentioned above and always
have it tuned to channel 3 or 4.  What I don’t know if the signal coming out
of the STB along co-axial will have true high-def (HD) content.  Even the
cable companies digital STB may output a signal on that co-axial that is
standard definition analog.  (see below for more comments on a variation of
this setup)



--Component Video  (red, green, and blue plugs)  digital output from these
plugs might be captured with some sort of video capture card.  Again this
functionality _might_ be incorporated with newer tuner cards.   (Again no
first-hand knowledge here, my older cards will have no such inputs).  With
this and the remaining setups you will also have to separately capture the
left and right audio output from the STB and into your line-in of the PC’s
sound card.



--S/Video (round plug) or Composite  (yellow plug) analog video signal that
can be captured with many of the PC tuner cards.   I wouldn’t even consider
messing with such low quality signal unless it will be viewed on an older
analog television.



Note that with all of these setups (sans the enigmatic wire-fire interface)
you will have to be able to control the STB from the PC.  Likely this will
be done thru an infrared (IR) signal.   MythTV is well equipped to do this
if you have the hardware.  M$ made a great little USB device that came with
their Windows Media Edition of XP not only can the device receive IR signals
from a normal hand held remote it also has something called a IR blaster
that can be used to output IR signals to a specific A/V component.  I have
one that I use the input to control my PVR.   I use the output to control my
surround sound amp.  This brings up another issue nearly all of the above
scenarios result in you losing surround sound information (if the cable
company provides it in the first place).   The wiring on these setups can
really be a mess, you could easily have upwards of: 3 component cables an 2
audio cables going from STB to PC along with a IR blaster cable going from
PC to the front face of the STB.





I would recommend getting started with a _greatly_ simplified setup then
building from there:    Rabbit  ears  --> co-axial -->  digital tuner device
--> motherboard.



This clean setup will allow you to quickly become familiar with whatever PVR
software you choose to use and a simple setup is _much_ easier to
troubleshoot.   Later you will appreciate this as you begin to potentially
add devices like a HDTV display, a surround amp. , IR device, plus all the
configuring you might like to experiment just within the PVR’s option.   Lastly
with  this setup you will get the best possible audio and video fidelity.
   The cable and dish companies compresses the signal and in the case of
Surewest they stripped out all the surround info.



Above  I used the term digital tuner device because one as has two viable
options here;

1)      An internal tuner card were digital audio and video streams are
captured and place on the data bus.  I’ve got an unused one.

2)      A external tuner box sold my HDHomeRun.  I have one of these and I
highly recommend them.  The box consists of a digital tuner (mine has two),
an antenna hookup, and an Ethernet port.  My PVR software, MythTV, already  has
this device as a configuration option.  With this tuner device I don’t use
up a cards slot and as a slight added feature my wife’s upstairs Window7
machine, or any other machine on the local network, can also control and
receive output from the tuner(s).



With either of these devices the PVR software will seamlessly be able to
tune to whatever OTA channel is needed.  Later once this setup is working
you might try to use the co-axial output from the STB instead of the OTA
signal.



I’ve never had cable except for the recent two month trial that was
ostensibly as a means to get access to all the of the NCAA basketball
tournament games.  I’ve since told people, “I can take or leave cable but I
will never go without a PVR”.

Good luck
Rod
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