* strange problem with KMC-4400R @ 2009-03-24 16:26 Ming Liu 2009-03-26 16:09 ` William M. Brack 0 siblings, 1 reply; 3+ messages in thread From: Ming Liu @ 2009-03-24 16:26 UTC (permalink / raw) To: video4linux-list Hi, I am working on KMC-4400R card. I tried to write a program to use two channels from the card by following the example program of V4l2. However, I met a very strange problem. When I kept capturing image, there were several lines following the moving objects like a ghost (sometimes more than one ghost) on the collected image. I can not figure out what causes this problem and how to fix it. The standard xawtv does not have this problem when only one channel is displayed. Any comments will be helpful and many thanks in advance. Sincerely yours Ming -- video4linux-list mailing list Unsubscribe mailto:video4linux-list-request@redhat.com?subject=unsubscribe https://www.redhat.com/mailman/listinfo/video4linux-list ^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: strange problem with KMC-4400R 2009-03-24 16:26 strange problem with KMC-4400R Ming Liu @ 2009-03-26 16:09 ` William M. Brack 2009-03-26 18:03 ` Ming Liu 0 siblings, 1 reply; 3+ messages in thread From: William M. Brack @ 2009-03-26 16:09 UTC (permalink / raw) To: video4linux-list; +Cc: Ming Liu Hi Ming, Ming Liu wrote: > Hi, > > I am working on KMC-4400R card. I tried to write a program to use two > channels from the card by following the example program of V4l2. > However, I met a very strange problem. > > When I kept capturing image, there were several lines following the > moving objects like a ghost (sometimes more than one ghost) on the > collected image. I can not figure out what causes this problem and how > to fix it. The standard xawtv does not have this problem when only one > channel is displayed. > > Any comments will be helpful and many thanks in advance. > The 4400R is a rather strange beast. There are, basically, four controllers (e.g. /dev/video[0..3]) and 16 inputs; each input can go to any of the four controllers, and the driver will also allow the same input to go to more than one controller. Each controller, however, can display only one input at a time. Your description sounds as if you are trying to use only one controller, and switch it's input back and forth between the two cameras. Assuming you have no more than four cameras (and you said, in this case, two), you should assure that each camera goes to a separate controller (i.e. instead of using "/dev/video0 channel 1" and "dev/video0 channel 2", for the second use "/dev/video1 channel 2". Hopefully that should give a "clean" image for both. > Sincerely yours > Ming > Regards, Bill -- video4linux-list mailing list Unsubscribe mailto:video4linux-list-request@redhat.com?subject=unsubscribe https://www.redhat.com/mailman/listinfo/video4linux-list ^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: strange problem with KMC-4400R 2009-03-26 16:09 ` William M. Brack @ 2009-03-26 18:03 ` Ming Liu 0 siblings, 0 replies; 3+ messages in thread From: Ming Liu @ 2009-03-26 18:03 UTC (permalink / raw) To: video4linux-list Hi, Bill, Thank you for the reply. Yes, I put one camera to "/dev/video0 channel2" and one to "/dev/video1 channel3" in my program. I tested in two computers: one xubuntu (8.04) and one fedora 6. The problem only happens in the xubuntu system. Even I replaced the capture card with another KMC-4400R, the problem reappeared on the xubuntu system. Any comments will be more than helpful. Sincerely yours Ming William M. Brack wrote: > Hi Ming, > > Ming Liu wrote: > >> Hi, >> >> I am working on KMC-4400R card. I tried to write a program to use two >> channels from the card by following the example program of V4l2. >> However, I met a very strange problem. >> >> When I kept capturing image, there were several lines following the >> moving objects like a ghost (sometimes more than one ghost) on the >> collected image. I can not figure out what causes this problem and how >> to fix it. The standard xawtv does not have this problem when only one >> channel is displayed. >> >> Any comments will be helpful and many thanks in advance. >> >> > The 4400R is a rather strange beast. There are, basically, four > controllers (e.g. /dev/video[0..3]) and 16 inputs; each input can go > to any of the four controllers, and the driver will also allow the > same input to go to more than one controller. Each controller, > however, can display only one input at a time. > > Your description sounds as if you are trying to use only one > controller, and switch it's input back and forth between the two > cameras. Assuming you have no more than four cameras (and you said, > in this case, two), you should assure that each camera goes to a > separate controller (i.e. instead of using "/dev/video0 channel 1" and > "dev/video0 channel 2", for the second use "/dev/video1 channel 2". > Hopefully that should give a "clean" image for both. > > >> Sincerely yours >> Ming >> >> > > Regards, > > Bill > > > > -- video4linux-list mailing list Unsubscribe mailto:video4linux-list-request@redhat.com?subject=unsubscribe https://www.redhat.com/mailman/listinfo/video4linux-list ^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2009-03-26 18:03 UTC | newest] Thread overview: 3+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2009-03-24 16:26 strange problem with KMC-4400R Ming Liu 2009-03-26 16:09 ` William M. Brack 2009-03-26 18:03 ` Ming Liu
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.