[sclug] Linux compatible Digital TV hardware?

Alex Butcher lug at assursys.co.uk
Tue Jan 15 10:30:59 UTC 2008

On Tue, 15 Jan 2008, Sebastian Malcolm wrote:

> I've got two hardware selections I need to make that I'd like advice with to
> ensure we get the best possible picture quality with a minimum of setup
> hassle; I'm happily running a Xen setup on this machine using stock Ubuntu
> kernel so I'd rather not recompile a custom kernel.
> (1) Graphic Card - PCI, PCIe-8x, PCIe-4x or PCIe-1x (or PCIe-16x with
> http://www.orbitmicro.com/global/express-adapter-p-755.html)
> I've been told that I should be able to get a very sharp image at the full
> native 1366x768 resolution using a DVI to HDMI adaptor or cable, so I don't
> need to spend the premium on a graphics card with built-in HDMI output or
> will I require that to watch Blue-Ray or HD-DVD with a Linux movie player?
> Any suggestions on a card with DVI (or HDMI) output that would be able to do
> the H.264 decoding to offload that from my CPU(s) that could be busy with
> recording video and/or compiling code? I've read that the nVidia drivers
> lack the "PureVideo" capability that exists in their Windows drivers to
> enable hardware accelerated decoding of H.264 video. I've read that nVidia's
> GeForce 6-series (>=6150) will at least do some hardware acceleration of
> MPEG-2 decoding.

My experience with my MythTV system is that the nVidia cards with the
proprietary driver are probably about as good as it gets, sadly. There
aren't any HD DVB broadcasts outside of Sky and London yet, so there's no
need to worry about H.264 yet either, I reckon. It'll probably turn up in
the nVidia drivers at some point, though. I use a Geforce 440MX in a Celeron
1.7GHz system, which is quite good enough to record 3 SD channels
simultaneously, whilst playing another.

> (2) USB DVB-T Reciever?
> I've reviewed the long list of USB DVB-T devices on LinuxTV.org Wiki and
> some of the info on MythTV.org but I'm looking for some more opinions for
> what spend (my girlfriend's) money on...

Not sure why you'd prefer USB. On the other hand, the Hauppauge Nova-T-500
dual tuner is USB internally, so there's very little in it. I use one of
these plus an old single-tuner Nova-T in my MythTV/FC8 box with no real
issues (bar losing a multiplex due to poor reception from time to time).

> Any reasons to buy a Card instead of USB?


> Perhaps to get 5.1 surround sound (SPDIF output) if that is broadcast here
> in the UK?

DVB is just MPEG over radio, so I don't see what you're getting at here.
Decoding the MPEG stream is a software process, and it'd be therefore down
to support for your sound output device as to whether you could get 5.1 out
of your SPDIF socket. Again, no broadcast 5.1 yet, as far as I know.

> We're wondering if any of you have a working configuration or any
> recommendations of any decent brands, which support Linux. Our criteria is
> that when used with appropriate software such as Kaffiene or MythTV are:
> - must be able to record and watch digital channels.
> - pause live TV option
> - preferably dual (can record one channel and watch another) but not
> necessary

Not sure you'll get a dual tuner in a single USB device.

> - a USB stick rather than a card so we can use it in other laptops around
> the house and when on the move

Right, handy, I suppose. On the other hand, if you have them installed in
your MythTV backend, you can just stream the recordings over WiFi or
Ethernet to your laptops.

> - preferably under ?100

According to pricerunner, Nova-T starts from 25 quid, Nova-T-500 (dual)
starts from 50 quid.

> - obviously must be Linux compatible.
> - remote control is preferable but not essential

The Nova-T-500 requires updated drivers for the remote to work, apparently.
This doesn't bother me, as I use the remote sensor attached to my older
Nova-T which JFWs with FC8's standard kernel and drivers. Both come with a
IR handset, batteries and sensor (at least in the retail packs).

> - connects to the wall aerial (we live in an apartment block so we doubt we
> have good reception with a stand alone aerial)

You might well want to invest in a decent amplifier/splitter, too. I have an
SLx 4 way model that I got from Argos, but it might be worthwhile trying to
find something a bit more 'pro' and a bit less 'consumer'. I made up my own
flyleads to avoid the use of gender changers and to keep the cable lengths
as short as possible. Unfortunately, I share a communal aerial between 12
other sockets distributed amongst 6 other homes...

> - would be _very_ nice extra to be able to receive (decode?) HDTV in the UK
> and Australia, but I don't know if that means it must be able to decode
> MPEG-2 or MPEG-4 ( H.264?). I think that in Australia 1080i is available via
> a MPEG-2 broadcast but here in the UK and elsewhere deploying HDTV the
> digital video stream will be MPEG-4, eventually?

AFAICS, this is a software issue. The card just pulls the MPEG streams off
the tuned broadcast multiplex and dumps it on the PCI bus.

> After extensive research over the weekend, we may buy the AverMedia brand
> because they provide Linux Drivers for some of their products, but I'm still
> unsure which model of thiers to buy because Driver Support for their latest
> models seems to be lacking. For example (despite Maplin's claim) the "Volar
> X" is the A815 model and lacks drivers but the "Hybrid+FM" A828 model does
> have drivers at avermedia.com: http://tinyurl.com/yuqq97. Product info:
> http://www.averm.co.uk/avermedia/aver/products_digitvtuner_dvbshybridA828.asp?show=1<http://tinyurl.com/yuqq97>

You won't be able to get the analogue and DVB parts of that device working
simultaneously, so don't let that be a deciding factor.

> Has anyone had any experience with the AverMedia products? If we go with the
> cheaper/older "Volar" (A808) model that lacks a remote control, then can
> someone recommend a USB IR Dongle and/or remote*?
> Many thanks,
> --Sebastian
> P.S. For a remote & IR USB Dongle, I guess I can just shop around for
> anything listed at http://www.lirc.org/.

Alex Butcher, Bristol UK.                           PGP/GnuPG ID:0x5010dbff

"[T]he whole point about the reason why I think it is important we go for
identity cards and an identity database today is that identity fraud and
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it is a view, I don't personally think it matters very much."
  - Tony Blair, 6 June 2006 <http://www.number-10.gov.uk/output/Page9566.asp>

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