View Full Version : Capturing 2 camera streams ?
12-14-2005, 03:07 PM
Is it possible to capture 2 camera streams in real time ? For the sake of argument Let say I have 2 dv rack instances , capturing 2 streams on 2 differenc hard drives with 2 cameras in 2 different firewire port would this , or something similar be fesable ?
12-14-2005, 05:44 PM
On the same computer? I don't think so... I don't think DV Rack lets you run two instances on the same computer...
12-14-2005, 06:19 PM
Ok but lets say I use DV rack for one camera and ... any normal capture software for the second camera ? Capturing both streams on two different physical HDs ? Would this be possible ?
12-14-2005, 08:01 PM
Well, now, that's an interesting question. Perhaps if you had two different firewire busses -- i.e., two different firewire cards. Don't know for sure. That might work.
12-14-2005, 09:27 PM
Ì shall try...
12-15-2005, 03:42 AM
A firend and I where dooign a VJ/screen gig (for fun..) adn messing aorund in teh booth we had an GL2 in with firewire and then we plugged in come JVC handycrapcam into another firewire port... After we re-booted, both the computer and camera, the JVC went back to the store with a dead firewire port. (computer and GL2 where fine [phew])
Sometimes you can cause [deadly] voltage spikes dooing that sort of stuff.. be carefull! ...and for god sakes don't try it with the first 2 HVXs off the production line!
12-15-2005, 03:57 AM
my question is WHY would oyu want to do this...?
12-15-2005, 05:18 AM
my question is WHY would oyu want to do this...?Cut down on the cost of a second laptop?
My instincts tell me that this will not work softtx. You can try, but I think, even if it were possible to manage 2 instances of DVRack (or 1 DVRack and one capture program), the dual streams of data to a 2.5" laptop hard drive might not make it intact. Perhaps if the hard disk ran at 7200RPM? Even then, laptops aren't built for IO intensive applications, so my guess is, if it works, you might get some drop frames. Of course, if you're talking a well equipped desktop, then my guess is there is a definite possibility to make this a reality.
I hope I'm wrong, because this would be practical.
12-15-2005, 06:29 PM
Ok here's my reason : I shoot a lot of conferences that I edit , encode and put online as 320x240 wmvs. These are shot in Montreal universities and hotels. I usualy go with 2 cameras.
My DVX100a witch is the A camera , and another smal minidv canon elura 80. I always go tapeless with dv rack on a computer ( not laptop ) for the capturing of the DVX shots. The conferences are almost always 2 hours and this way I dont put ridiculous stress on the DVX heads to film a static guy talking.
I put a 80 minutes tape running in LP in the Canon giving me 2 hours of continuous recording with a slithly wider angle. This recording while being used in the editing , also works as a tape backup if anything goes wrong with DV rack ( never happend - touch wood ).
But now I would LUV to record the Canon stream on the same computer. This would reduce the time of post significantly. I would not have to spend 2 hours ( sometimes more ) capturing the canon recordings. And thus i could go on right away to resizing and encoding in virtualdub to get the clips ready for the editing and the final encoding in premiere ( I have a wierd method here , but beleive me it gets me the best results by far ).
Please excuse this very long and boring introduction in a very bad english ( i speak french ) but please bare with me another few lines ,
So here's my idea :
First of all i dont use a laptop. Im building a computer inside a 1500 Pelican case. A normal amd based computer with a microatx motherboard , two 7200rpm hard drives with a total of 370Gig of space , 1 gig of RAM and a 14inch lcd screen skrewd in the opening top. The computer has a 3 port firewire card and it also has 1 build in firewire port in the mobo.
So what I would try is this : The first camera in the firewire card capturing thru DV rack on the "C:" hard drive. The second camera in the motherboard's firewire port capturing the stream on the "d" hard drive with ...hmmm... WinDv ? Premiere ? any suggestions ?
Im pretty confident this is possible, Im sure the RAM nor the CPU would mind, not to sure about the OS though .... Anyway I can not try this before next week when I get both the cameras back, and also i wanted to discuss this here first , better safe than sorry...
Any more thoughts on this ?
P.S. I realized a bit late that I posted this is the technical forum for the HVX and not the DVX one . My mistake really.