DVB-T Questions

[Master Yoda]

I was pondering on getting a DVB-T card for my pc as there are a fair number of channels on it and its also freeview.Would get a DVB-S card apart from the fact i need the sky card to decripe the channels and ive not seen and DVB-S cards, So DVB-T seems a good way to go, So a couple of things though...

1.Am i right in thinking that with a DVB-T card when capturing i can get the actual dvb stream rather than having to capture to avi and then convert to mpeg2 for dvd. And is DVB-T transmitted in 16.9 depending on the program like Sky is ?
2.On avg how much space is a stream going to take up ?
3 What good DVB-T cards are there ?? i went to get as good a picture as i can and captured in wide if avalible. Was looking at ...

Compro VideoMate DVB-T200 Digital TV Internal
Compro VideoMate DVB-T300 Digital & Analog TV
Hauppauge WinTV-Nova-T PCI Adapter
K-World V-Stream Xpert DTV Digital TV Terrestrial

Both Compro ones support HDTV.... Just thing ahead in case any freeview channels start doing HDTV in the future.

[DrP]

1.Am i right in thinking that with a DVB-T card when capturing i can get the actual dvb stream rather than having to capture to avi and then convert to mpeg2 for dvd. And is DVB-T transmitted in 16.9 depending on the program like Sky is ?
Yes. The card's software dumps whatever is transmitted to a file. You usually have a few choices of the file format, transport stream, .mpg etc. If your TV network sends MPEG/2 then that is what ends up on your disk. No recoding needed. As for the aspect, that depends on the channel. Freeview is a many varied thing. Some channels do things like displaying 544 x 576 as 16:9 which is going to give poor quality, while others use 544 x 576 as 4:3 with others doing 720 x 576 16:9.

2.On avg how much space is a stream going to take up ?
That varies a lot. Especially with the widely varying bitrates used in the UK. Some video is run at an average of 3Mbit/sec and audio at 192k/sec, so that might give you an idea as to what sort of disk space usage you can expect. Its orders of magnitude less than you would be used to for a straight analogue capture.

3 What good DVB-T cards are there ?? i went to get as good a picture as i can and captured in wide if avalible. Was looking at ...

Compro VideoMate DVB-T200 Digital TV Internal
Compro VideoMate DVB-T300 Digital & Analog TV
Hauppauge WinTV-Nova-T PCI Adapter
K-World V-Stream Xpert DTV Digital TV Terrestrial

Both Compro ones support HDTV.... Just thing ahead in case any freeview channels start doing HDTV in the future.
Any DVB-t PCI card will handle HD because the card is just a bridge to get the DVB data into your PC. It really comes down to the software used to display the picture. When it comes to USB devices, a USB2 device is needed to be able to cope with the bitrates that HD MPEG/2 requires. How well things go really boils down to the drivers and software that come with the card. If the card has good BDA drivers, there is an increasing pool of good free software out there to choose from. Lots of people think webscheduler (http://dvb-ws.sourceforge.net) is the best thing since sliced bread when it comes to BDA recording programs.

[Master Yoda]

Thanks for the info, if i get one i'll think i will go with one of the Compro VideoMate cards as they actually say they support HDTV and says it supports MS BDA drivers(not quite sure what bda drivers are). If anyone with Freeview knows any more about the AR thats transmitted that whould be a great help.

[digidragon]

Most channels on freeview are broadcast in 16:9. The main exceptions are the music channels, and one of the shopping channels. The main channels use full resolution, but the others, like ITV3, ITV4, E4 etc. use 544 x 576

[Master Yoda]

I see, so the likes of BBC1,BBC 3 and ITV are at full res.

I am now also looking at the Nebula Digitv card, seems to be really good. The official site for it says it supports HDTV but no where else seems to,can anyone comferm.

[digidragon]

Yes, all the BBC channels, plus ITV1, Ch4, and five are full resolution. Most of the others are below full res.

The new (beta) software for the nebula card (which I have) mentions an HDTV (presumably h.264) licence. The card is sold in Australia where they have MPEG2 HDTV, so it's obviously capable of receiving/preocessing HDTV.

[Master Yoda]

OK, the only gripe i have with the nebula is the price, its a bit more than what i wanted to spend due to the fact i will proberly only be capping the odd program here and there, dont think i will be watching tv that much on my pc.

[DrP]

I have no idea what cards go for in the UK, but digitalnow (http://www.digitalnow.com.au/dvbtcards.html) site has a few options. I have a DNTV Live! Low Profile (LP), it works well enough with webscheduler and doesn't have any reception issues. I'd rate it at least as good as the older style Technotrend budget cards with a Philips tuner onboard for reception. The card uses a CX2388x bridge instead of the BT so its way less prone to packet corruption due to PCI bus contention than earlier generation cards.

One of the big tricks the Nebula software can do (AFAIK) is record different programs from the same mux into separate files. webscheduler can't do that (yet; its Australian based and we have stuff all channels, only ABC really has two channels in its mux so there has been no real call for the option), it'd have to dump the entire transport stream and then you'd have to pull out the bits you wanted to keep.

[digidragon]

Yes, the Nebula is relatively pricey, but they're always improving the software and adding new features like the virtual tuner feature whereby you can record any/all of the channels on the same mux even if they're broadcast at the same time. Some muxes have six channels, so it may prove useful. It's also on sale at the moment.

It also has the option to record in DVD-authoring format, so that you don't need to convert the MPEG from a transport stream to a program stream.

[Master Yoda]

I see, so whats the difference between the transport stream and program stream ?

[digidragon]

I don't know the technical details of why they're different, but if you try to author a transport stream to DVD, the authoring software will say the MPEG is invalid. It needs to be run through something like PVAStrumento or VideoRedo to convert it to a program stream MPEG first.

[Master Yoda]

So do those two re-encode the file like cce or does it just change headers ??

[digidragon]

No, it doesn't re-encode the video at all, I think it just changes the format of the MPEG container.

[bond]

transport and program stream are two totally different containers, like .asf is a different container than .ogg

[Master Yoda]

I see, so after the program dumps the digital stream i would need to run it through one of the two programs digidragon mentioned to be able to author it on dvd with the likes of scenarist.

[bond]

i dont know how tv streams are mastered, but i would assume they are not compliant to the dvd specs, so you would need to reencode them anyways

but as i said i am not sure

[savage747]

I frequently do DVB-T recordings (Avermedia card and Linux here). I cut and demux the resulting files (.ts) in ProjectX, mux it to normal .mpg with mplex and create a DVD using DVDstyler. The result plays fine on any DVD player I could find (eh, two ;) ) - no recoding needed (although the DVB and DVD spec differ a bit - allowed resolutions, GOP length etc. IIRC). I guess that integrated MPEG2 decoder chips are designed to be used in both DVD players and DVB decoders so they tolerate anything that looks like MPEG2... ;)

[bond]

I frequently do DVB-T recordings (Avermedia card and Linux here). I cut and demux the resulting files (.ts) in ProjectX, mux it to normal .mpg with mplex and create a DVD using DVDstyler. The result plays fine on any DVD player I could find (eh, two ;) ) - no recoding needed (although the DVB and DVD spec differ a bit - allowed resolutions, GOP length etc. IIRC). I guess that integrated MPEG2 decoder chips are designed to be used in both DVD players and DVB decoders so they tolerate anything that looks like MPEG2... just because it plays in your player doesnt mean you have a compliant dvd tough ;)

[digidragon]

The MPEGs broadcast by the main channels are DVD-compliant. TMPGEnc DVD Author is very fussy about this and won't accept them if they're not. Some of the minor channels broadcast in lower resolutions, but DVD Lab will author these, even though they're not strictly compliant.

[DrP]

DVDPatcher for Windows users will take care of TMPGEnc's fussiness in a moment or two.

[Master Yoda]

OK, Thanks for the info. At least i now know that i dont need to mess about re-encoding like you would if capping to lowloss avi and the encoding to mpeg2.

Think i will try and get the Nebula DigiTV card after reading some reviews

[Ac3Dc3]

you really can do most everything with the wintv that you can with nebula, if you ditch the wintv software.

just dont let the all singing and dancing gui determine your choice. the fact is, they keep comming out with new betas with useless new features that break a lot systems. and with the nebula, once you go BDA, you can never go back i.e. can no longer use their software.

a big plus is the ability to record analogue, that the wintv lacks. but if your not planning a large VHS to DVD conversion or something similar, its kind of pointless.

and remember, there maybe some Nova-Ts on ebay as the novelty of new Christmas toys wares off

Ac3Dc3.

edit: nb high-def DVB-T wont be available in the UK for a long time

[Master Yoda]

I'll check out the WinTV Nova-T. Is there any difference between the MCE version and a standard version or is it just the software ?

[digidragon]

Just to defend Nebula and their betas... betas are not meant to be stable, users install them at their own risk.

And regarding the BDA drivers, of course you can go back to using the DigiTV software. You just need to manually re-install from device manager.