DVI --> HDTV capture

[fisix]

We need to take dvi output from one computer (at 1080p, 60Hz) and capture it as HDTV on another. rendering directly seems to be a problem: the end result will be a demo reel, so the source computer needs to be rendering in real time (for user interaction), which so far seems to preclude running the capture on the same pc.

so, hardware wise we need something like dvi in, preferably with no HDCP limitations.

anyone have some ideas?

[Blue_MiSfit]

Hah.

Good luck.

The only thing I can think of is analog component video out -> HD capture card (BlackMagic Decklink / MultiBridge etc...) They are very pricey.

Exactly why can't you just capture the desktop on the host computer?

~MiSfit

[fisix]

we can't capture the desktop because the resources of the computer are maxxed out just running the realtime render.

we've decided to go the pricey route, though it limits us to 30fps, for now...

[Blue_MiSfit]

Wow.. so you bought a Decklink card just for this project :)

Cool.

If you do 720p, then you can get 60 fps... or 1080i is 30fps (But 60 pictures per second because of interlacing)


Did some research, and there ARE some cards that can record straight from VGA/DVI, but they are even more expensive then the Decklink cards, and are limited to 1600x1200@60Hz at the most.

1080p60 is essentially out of reach.. Maybe some evil device buried in a secure bunker in the depths of ILM has this capability surely provided by an unholy alliance with the dark side of the force....

But not the average video lab :D

~MiSfit

[easy2Bcheesy]

We are working on a 1080p/60 capture hardware solution right now that will allow for 1920x1080 at 60fps capture directly from VGA, DVI and unencrypted HDMI into the CineForm HD codec.

In theory it should also allow for simultaneous 720p/60 capture from two different sources, as it has dual head input.

In terms of colour depth, we should be able to do YUY2 1080p/60 directly into CineForm and all being well, 1080p/60 into the new 4:4:4 CineForm codec, though the latter may well end up requiring dual quad core Xeons.

First tests of the hardware configuration should be in the next few weeks. By the end of the year we should have a single channel input portable solution.

In the here and now, the only solution for the OP is a Gefen DVI to HD-SDI converter, then run in with a Decklink or Xena card. This is hugely expensive though and as the OP states, the 60Hz input isn't preserved. Every other frame is dropped, producing 1080p/30. Personally I'd be building a dual quad core Xeon machine with a meaty RAID array, then just run FRAPS on it. At least then the investment will continue to pay off after the video capture is done.

[Blue_MiSfit]

wooooooooooooooooooooooot.......

Wow. 1080p/60 directly into 4:4:4 CineForm. That's pretty much all you need right there...

If only CineForm was available for mac! (It is, but it's not finished yet... if only Apple allowed people access to FCP's RT engine...)

And finally, if only I could afford CineForm :D

~MiSfit