Thread: Cameras (+IMUs)
View Single Post
  #13   Spotlight this post!  
Unread 24-01-2016, 13:18
BitTwiddler's Avatar
BitTwiddler BitTwiddler is offline
electronics/programming mentor
AKA: Mr Tanguay
FRC #1726 (N.E.R.D.S.)
Team Role: Mentor
 
Join Date: Oct 2008
Rookie Year: 2006
Location: Sierra Vista, AZ
Posts: 243
BitTwiddler is on a distinguished road
Re: Cameras (+IMUs)

Quote:
Originally Posted by Greg McKaskle View Post
It can work, but logistical things can get in the way. For LabVIEW, the USB cameras are enumerated on the robot and sorted using VID/PID and serial number to try and get them to stay in the same order. It is silly, but it may be easier to predict if you use two different types of webcams. Once sorted, they start at USB 0 and go up from there.

If you save a copy of the Vision Processing VI to a new name and make one for each camera, that is one approach. Or you can make another loop inside of the VI.

Our team is using one camera for driver and one for processing. I did the two loop approach. We also decided to do an Axis for driver and a USB for targeting. The Axis has better flexibility for compression and streaming and doesn't need CPU resources while the USB is nice for the targeting cam.

I'm pretty sure the default dashboard defaults to USB 0. So if you want it to point to the other USB cam, just build from a template and change that one address. Similarly if you choose to go with an Axis instead, change the address. Keep in mind that USB HW option gets a compressed image from the camera, meaning the cRIO only needs to copy the data and not run the jpeg compression like it will if you use USB SW.


If you have issues or questions, just ask.

Greg McKaskle
Thanks for this Greg. You've cleared a few things up. After digging into the vision processing VI I now see how the image gets to the DB. Looks like most of the work routing the DB image is done in the the "CameraBackground Loop" VI. I'll let you know if we have difficulties working with this. Right now I have a lot to learn about video image routing.
Dave Tanguay
Reply With Quote