My list of HD questions...

[lonegeek]

How big is a 30 minute recording in mpeg 2 format?

Which is the best HD OTA card to get?

How can i set it to 720p or 1080i? Does that depend on my output resolution of my graphics card?

How fast of a cpu can record HD and display it good?

Will it still look fine on a SDTV?

Does it record AC3/Dolby audio?

Will a soundcard with dolby decode it and output to 5.1?

Will spdif decode ac3/dolby and output to 5.1?

More question to come?

zach

[sub]

How big is a 30 minute recording in mpeg 2 format?

It can vary wildly. The bitrate is set by the broadcaster.

Which is the best HD OTA card to get?

I dont know. I've never owned one myself, so I've had very limited exposure to these US ATSC devices.

How fast of a cpu can record HD and display it good?

Your CPU doesnt need to be particularly fast to record, but playback will require a fair bit of grunt. I'm relucant to guess, so I'll leave this to someone in a country with HDTV. I'd also recommend a fairly decent video card.

Does it record AC3/Dolby audio?

Yes, if that is what is transmitted by the broadcaster.

How can i set it to 720p or 1080i?

You cant. This is set by the broadcaster.

[lonegeek]

How can i set it to 720p or 1080i?

Well on tvs you can set hd output as differnt resolutions



Around what size are 30 minute recordings? Like right now im at 1.4gb for high quality on SD, thats 9mbps.. HD is usually 15mbps here..or so...Roughy 2.5gb per half hour?

[sub]

How can i set it to 720p or 1080i?

Its up to the broadcaster to decide if a show is transmitted as 720p or 1080i. GB-PVR just recordings the digital stream to disk (ie, does not change the resolution or framerate).

Playback resolution is entirely up to you (ie, whatever you have your desktop resolution set to).

Around what size are 30 minute recordings? Like right now im at 1.4gb for high quality on SD, thats 9mbps.. HD is usually 15mbps here..or so...Roughy 2.5gb per half hour?

Depending on the show/channel it'll be somewhere between 1.8GB for 30 minutes, up to about 4GB per 30 minutes. It can vary wildly.

I recently saw a comment saying CBS typically takes 7gb per hour and NBC slightly less. Both of these stations broadcast at 1080i. Fox and ABC take about 5 gb per hour and broadcast at 720p.

[zed]

When I had a Fusion5 Lite tuner card I was seeing about 6G per hour of 1080i in dvr-ms format. That was for PBS.

[bgowland]

How fast of a cpu can record HD and display it good?

I can't say for ATSC but I've captured stuff from the BBC HD1 channel in the UK (1080i). Playback using a software decoder on my 2.4GHz P4 ranged at between 6-10fps. Very pretty pictures but obviously unusable other than for test purposes.

I'm told a better graphics card might improve things but I still wouldn't expect to see 'real-time' playback unless I changed my CPU.

As for filesize for recordings, I see about 100MB per min so similar to what zed said.

Cheers,
Brian

[lonegeek]

I can't say for ATSC but I've captured stuff from the BBC HD1 channel in the UK (1080i). Playback using a software decoder on my 2.4GHz P4 ranged at between 6-10fps. Very pretty pictures but obviously unusable other than for test purposes.

I'm told a better graphics card might improve things but I still wouldn't expect to see 'real-time' playback unless I changed my CPU.

As for filesize for recordings, I see about 100MB per min so similar to what zed said.

Cheers,
Brian

What kind of graphics card where you using?

[bgowland]

What kind of graphics card where you using?

It's an ATI Radeon 7000 AGP (4x) with 64MB 64Bit DDR DRAM (at least that's what it says on the box ).

It was pretty cheap as my PVR was always designed just to work with an MVP so I didn't need anything fancy.

The only reason I'm led to believe a better graphics card might help is based on the hardware recommendations on the CoreAVC site...

http://coreavc.corecodec.org/recommend.html

I tried a number of combinations including the onboard Intel Extreme graphics with the MainConcept/Elecard H.264 codec (perhaps 6-7 fps). Adding the Radeon card improved things slightly.

I then managed to get hold of a pre-release version of the CoreAVC codec that they developed to include support for the UK HD format. That was when I managed to get 10fps consistently with some stuff running better than that (but no better than maybe 15fps).

Cheers,
Brian

[lonegeek]

How did you find out the fps?

[bgowland]

How did you find out the fps?

I rendered my own graphs in GraphEdit then looked at the Quality property page on the VMR9 Renderer. I'd expect it to be reasonably accurate but who can tell? That's why I used words like perhaps/maybe - just ballpark figures.

Another way is just timing - if a 1min recording at 25fps takes 2mins 30secs to playback then that's 1500 frames over 150 seconds hence 10fps. Again, just ballpark - it seemed about right though.

Cheers,
Brian