Multiple iSight Cameras


    Sep 11 2006 | 4:59 pm
    Hi all, I am attempting to correlate data from two obliquely angled iSight cameras in order to do 3D motion-tracking. However, when I plug in both cameras, my Mac just freaks out. The framerate fluctuates between 2000 and nearly 0, the images - if they exist - are distorted, and then Max hangs. If I look in system profiler, I can see both cameras along with two unknown devices. These two devices are apparently my root Firewire bus and the hub I'm using for the two cameras - at least that's my best guess, since unplugging the external hub makes one of them disappear. I must admit I'm a Windows native, so I don't know how to manually add and remove devices if the system isn't detecting them properly. I've tried using the same two cameras without a hub as well, so the hub is not the issue. I have tried everything I can think of including manually resetting the Firewire bus as per instructions on the Apple support site - unplug the computer for 5 minutes, then try again. Both cameras work independently, but using them both causes problems.
    The Compy: Quad 2.5 Ghz G5 6.5 GB Ram Running 10.4.7 Both cameras have the iSight 1.3 firmware update.
    I've done a lot of searching on this, and what I can find seems to amount to many people having this problem and the few who don't saying "mine works fine..." Any suggestions?
    Cheers, Mike

    • Sep 11 2006 | 9:14 pm
      hm, i used that patch with 3 cam inputs on a g4 powerbook with a hub.
    • Sep 11 2006 | 11:53 pm
      Thanks for the help. That patch works for me as well, but unfortunately does not address my issue. I need to get video from both cameras simultaneously.
      Cheers, Mike
    • Sep 12 2006 | 5:37 am
      I m sorry to say, but you won't be able to acheive that. as far as I can remember, the iSight driver only accepts on cam at a time.
      //yac > > Thanks for the help. That patch works for me as well, but unfortunately does not address my > issue. I need to get video from both cameras simultaneously. > > Cheers, > Mike >
    • Sep 12 2006 | 11:12 am
      but the patch has the cams running simultaneously. the gate just decides which jit.grab gets the bangs. if it is too much for the computer, you could switch between the grabbers in an 20 ms interval -> since the camera would provide you with a new image every 40 ms anyway. maybe you could post the grabber part of your patch.
      On Sep 12, 2006, at 1:53 AM, Mike Sayre wrote:
      > > Thanks for the help. That patch works for me as well, but > unfortunately does not address my issue. I need to get video from > both cameras simultaneously. > > Cheers, > Mike >
    • Sep 12 2006 | 2:54 pm
      Hmm, would it be possible to do some sort of hack that had two instances of the driver running, or some such wizardry? I will let 'you know how the alternating thing works out.
      Many Thanks, Mike Sayre
    • Sep 14 2006 | 2:57 am
      The alternating idea didn't work. It just froze like before. It seems that the problem must be with the camera driver. I wonder if it might be possible to kludge a driver using the cvcam component of OpenCV. Anyone ever try doing something like that?
    • Sep 14 2006 | 9:29 am
      > The alternating idea didn't work. It just froze like before. It seems that the problem must be > with the camera driver. I wonder if it might be possible to kludge a driver using the cvcam > component of OpenCV. Anyone ever try doing something like that?
      just to say, if you don't find your way with iSights, Unibrain Fire-i do accept chaining: http://www.unibrain.com/Products/VisionImg/Fire_i_DC.htm and it's cheap: http://www.firewire-1394.com/fire-i-webcam-unibrain.htm
      //yac
    • Sep 14 2006 | 11:32 am
      i think i posted this a while back, it uses 6 the unibrain cameras no a mac for 360 panorama http://www.vrhotwires.com/InexpensivePanoramicVideo.html 2006/9/14, Yacine Sebti : > > > The alternating idea didn't work. It just froze like before. It seems > that the problem must be > > with the camera driver. I wonder if it might be possible to kludge a > driver using the cvcam > > component of OpenCV. Anyone ever try doing something like that? > > just to say, if you don't find your way with iSights, Unibrain Fire-i do > accept chaining: > http://www.unibrain.com/Products/VisionImg/Fire_i_DC.htm > and it's cheap: > http://www.firewire-1394.com/fire-i-webcam-unibrain.htm > > //yac >
    • Sep 21 2006 | 10:12 am
      I don't have 2 iSights to test with, but a little searching around the web (links below) indicates that the iSights (depending on resolution) are pumping out too much data to work simultaneously on a single bus. I would argue that Max shouldn't freak out in this manner, but until such time as I can test this myself, I don't have a fix for that. Sale of iSights is now prohibited in Europe (lead is used somewhere within the thing), so it won't be anytime soon.
      You might try the Quartz Composer patch mentioned in the 2nd link and let me know how that works, too.
      jb
      Am 11.09.2006 um 19:00 schrieb Mike Sayre:
      > > Hi all, > I am attempting to correlate data from two obliquely angled > iSight cameras in order to do 3D motion-tracking. However, when I > plug in both cameras, my Mac just freaks out. The framerate > fluctuates between 2000 and nearly 0, the images - if they exist - > are distorted, and then Max hangs. If I look in system profiler, I > can see both cameras along with two unknown devices. These two > devices are apparently my root Firewire bus and the hub I'm using > for the two cameras - at least that's my best guess, since > unplugging the external hub makes one of them disappear. I must > admit I'm a Windows native, so I don't know how to manually add and > remove devices if the system isn't detecting them properly. I've > tried using the same two cameras without a hub as well, so the hub > is not the issue. I have tried everything I can think of including > manually resetting the Firewire bus as per instructions on the > Apple support site - unplug the computer for 5 minutes, then try > again. Both! > cameras work independently, but using them both causes problems. > > The Compy: > Quad 2.5 Ghz G5 > 6.5 GB Ram > Running 10.4.7 > Both cameras have the iSight 1.3 firmware update. > > I've done a lot of searching on this, and what I can find seems > to amount to many people having this problem and the few who don't > saying "mine works fine..." Any suggestions? > > Cheers, > Mike