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Kay
January 3, 2005, 18:10:16
Hi,

I'm investigating the use of 3D imaging. I would like to capture two sources of video and display them for stereoscopic viewing.

Questions:

1 - Is it possible to have two DFG/SV1 frame grabbers installed in the same PC?

2 - Will your SDK allow me to capture the frames from the two frame grabbers?

Thanks,

Kay

Johannes Vogel
January 4, 2005, 13:31:53
Hello,

The answer to the two questions is yes. But there are a few things to consider:

a) If you want to capture color images, you have to reduce the horizontal resoluton to 320. Monochrome is no problem.

b) Stereo applications require the two cameras to be synchronzed. Even if you are able to synchronize the cameras, there is no easy way to synchronize the two image streams coming from the two grabbers.

Kay
January 4, 2005, 17:58:03
Johannes,

Thanks for the response.

1 - What is it that limits the resolution to 320 if I use two frame grabbers? Is it the bandwidth of the PCI bus?

2 - If the frame grabbers are free running, wouldn't each CListerner object get a callback with a frame of video when the corresponding frame grabber card A/D the S-Video coming in?

Johannes Vogel
January 5, 2005, 10:30:00
Hello,

It is the output FIFO of the BT878 chip that limits the horizintal size to 320 if two grabbers are operated simultaneously in color mode.

You get calbacks for the two grabbers (because you have to use two grabbers objects). The problem is that you have to use the time stamps of the images buffers in order to determine which buffers belong together.

Kay
January 5, 2005, 15:33:07
Johannes,

What if instead of two DFG/SV1 grabbers, I use 1 DFG/SV1 grabber and 1 DFG/1394-1 box. Will that allow me to get two frames at 640x480 resolution?

Johannes Vogel
January 6, 2005, 13:48:00
Hello,

this will work.