[sclug] Linux compatible Digital TV hardware?

Tom Carbert-Allen tom at randominter.net
Tue Jan 15 11:19:16 UTC 2008

We aren't even going to have HD DVB-T by 2012 acording to recent ofcom 
rumours. despite the fact most other countries in Europe will be getting 
the UK olympics in 2012 in HD.... (not that I wanted the olympics 
anyway) But it is a bit of am embarasement for the UK IT/TV industry.
They even went as far as saying SKY can't show HD olympics because it 
won't be available on freeview and olympics has to be fair access to 
all...go figure. I bet it will be on one of the FreeSat channels though, 
but probably in a euro language.


Dickon Hood wrote:
> On Tue, Jan 15, 2008 at 10:30:59 +0000, Alex Butcher wrote:
> : 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,
> The London HD-on-DVB-T trial has ended.
> : so there's no
> : need to worry about H.264 yet either, I reckon.
> It's coming, though.  Not sure when.
> : 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).
> Not all the USB devices will ship the entire multiplex to the host CPU for
> filtering.  This may or may not be an issue for you.
> : >Any reasons to buy a Card instead of USB?
> : Tidiness?
> Less host CPU usage, too.  USB really is quite evil.
> : >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.
> AC3 5.1 encoded sound in the bitstream.  As yet, no, not present on
> SD Freeview, but the BBC HD stream had it, and the DVB-S HD streams have
> it.
> : 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.
> Correct, although there is some Pro-Logic stuff encoded in the PCM output
> stream as usual on some services.
> : >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.
> There's technically no reason -- a multiplex is only about 27Mb/s, after
> all -- but I've not seen one, either.
> : >- a USB stick rather than a card so we can use it in other laptops around
> : >the house and when on the move
> Assuming you have reception.  Portability is less useful than you'd
> imagine.
> : 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.
> I'd avoid wifi.  It can be done with a decent AP, but not all seem to be
> able to handle the packets per second.
> : >- preferably under ?100
> : According to pricerunner, Nova-T starts from 25 quid, Nova-T-500 (dual)
> : starts from 50 quid.
> Nova-T is a budget card with no output hardware.  It's quite capable of
> dropping the complete multiplex to the host, which allows you to record
> all the services on that multiplex simultaneously.  This may be useful,
> although as MythTV *still* can't do it, it may not.
> The 500, assuming it's the PVR 500, is a 'full-featured' card, with output
> hardware.  It filters on the card, and may not be capable of passing the
> complete multiplex.  It also has decoder hardware on board, which is
> useful for low-spec hosts.
> : >- 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)
> Signal around here isn't all that good anyway...
> : 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?
> Current DVB standards deploying in the UK are MPEG 4 H.264 (not just MPEG
> 4; that's something different).  Sky is using 720p50 for some content, and
> 1080i25 for others; the BBC is sticking to 1080i25 until 1080p50 becomes
> possible.  17Mb/s per channel, roughly, for both these standards on dsat;
> they're looking at about 5Mb/s for Freeview, if that ever happens.  It'll
> look crap.
> : 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.
> Near enough.  The full-featured cards may not handle H.264 in hardware on
> the output.  This may or may not matter, depending on how future-proof you
> want it.  Frankly, given we're some years off HD on DVB-T, it probably
> won't.

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