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Sarreq Teryx
23rd February 2003, 22:24
http://www.gnu.org/software/gnuradio/gnuradio.html

right now they're using a us$1300 ADC card with this (which is supposed to be low cost for this type of thing :eek: ), does anyone think this can eventually be made to work with a regular TV card? I would think to actually play the video back you'd need a much-more-powerful-than-what-I've-got CPU and a massive HD though, they're pulling a 19.2Mbit 2730x1088 (rectangular pixels again, what gives?) MPEG-2 stream, and not converting it down (cause you couldn't in real time yet)

The main reason I'm asking is that I'm wondering if an entirely software based HDTV decoder would work with an analog TV card, and if so, why the frutz are true HDTV cards and set-tops so bloody expensive

trbarry
23rd February 2003, 23:26
I have no idea why they are so expensive, except maybe they don't expect to sell many yet.

But the old WinTV-d card could receive HDTV and store it to disk in a form that a fast machine running WinDVD could mostly play. And the WinTV-d cards can be found discounted down to a little over $100.

I think the new Dvico Korean software only cards are only about $160 before you get to shipping and taxes and stuff. But they are software decoding, but (AFAIK) not software demod.

- Tom

Sarreq Teryx
2nd March 2003, 22:09
That's not the problem, I have the WinTV-HD card, but it refuses to work alongside my Radeon All-in-Wonder 8500DV (and hauppage replied to one of my e-mails basically saying it will never), and being able to see my desktop is a bit more important than being able to record HDTV streams. What I'd like is to do, since it supposedly (by it's box, and several dozen reviews anyway, their tech support says otherwise) is able to decode HDTV streams in hardware, is be able to use my AIW to view HDTV, but there's no built in way to do so. I really wouldn't need the part that actually controls how the radio signal is recieved (it's still the same 6MHz channelling as NTSC after all), just the part that can decode the digital encoding from the signal and then either save or watch the output

trbarry
3rd March 2003, 00:31
I have no idea how you would get a demod function out of a Radeon except pure software.

But why doesn't the Radeo 8500 DV work with the WinTV-HD. For full HD of course you have to hook the WinTV-HD card to a RGB or YPbPr Tv input. But is it just the pass through that's broken?

I used to have a WinTV-HD, a few cards ago. The software was primitive, but the reception hardware worked okay.

- Tom

Sarreq Teryx
3rd March 2003, 01:44
But why doesn't the Radeo 8500 DV work with the WinTV-HD. For full HD of course you have to hook the WinTV-HD card to a RGB or YPbPr Tv input. But is it just the pass through that's broken?
Not the HDTV output, that and the dongle work just fine as far as I know, it's that the wintv-hd refuses to work software-wise with the AIW also installed.

And the TV connection isn't absolutely necessary either, my monitor runs at 1920x1080 just fine, that's actually what I've had my desktop resolution set to since my last vid card (geforce3, broke under store warrantee, AIW was the 6 month later equivalent) (you have to add the mode with powerstrip or similar), and switching to fullscreen with the wintv-hd, there's no mode change.

Sarreq Teryx
15th March 2003, 03:41
slight bit more info
http://www.salon.com/tech/feature/2003/03/12/spectrum/index.html?x
http://www.reed.com/dprframeweb/dprframe.asp?section=paper&fn=openspec.html
http://www.its.bldrdoc.gov/meetings/art/art02/slides02/ree/ree_slides.pdf

trbarry
15th March 2003, 14:22
Sarreq -

Thanks, those papers represent a fascinating idea, even if I don't really understand it. ;)

But it looks like we could evolve to have a vast amount of spectrum available instead of a carefully parceled shortage. Maybe this sort of thing will pop up on some the unlicensed Wi Fi spectrum bands.

- Tom