Images cut

Post Reply
Posts: 8
Joined: Mon Oct 01, 2007 7:46 am

Images cut

Post by Manium » Fri Jul 16, 2010 8:42 am


I have a problem when using Tracking Tools 2.2 with 21 V100R2. There are about 20 markers in the scene.

The problem is that the images seem to be cut... Only the top of the image appears.
The "Frame Queue overflow" is only shown when zooming on the images.

The computer is an Intel Core 2 Duo 3Ghz with 3 Gb, running on Win XP.

Two USB-hub (7) are used to connect the cameras. The others are directly connected to the pc.

What's wrong?

Thank you!

Posts: 1139
Joined: Thu Jan 30, 2003 5:00 am
Location: Corvallis, Oregon

Re: Images cut

Post by Birch » Fri Jul 16, 2010 1:43 pm

Precision grayscale mode consumes more bandwidth than other processed video modes, especially for large objects. You may be maxing out the USB bandwidth available to the camera, causing the remaining part of the video frame to not be transmitted.

You can check the bandwidth used by changing the following setting :
app menu -> edit -> tracking tools settings -> verbose camera info -> true

To resolve the issue you could either use smaller markers or try changing to a different processed video mode (segment, hardware object, etc).

Here is more information about the different video modes.


Camera Processing modes
These options select the in-camera video pre-processing mode.

Segment : Standard marker detection. Provides a balance between precision and USB bandwidth use.

HW Object: Most efficient marker detection. Provides more efficient USB bandwidth utilization, but delivers less marker information to Arena's 3D reconstruction engine than the other modes.

Precision Greyscale: Most precise marker detection. Calculates marker locations using full grayscale data for each marker, provides greater accuracy than other modes. It requires more USB bandwidth and is not recommended for any cameras which share a USB EHCI controller with a V100 operating in Scene A/V mode. It is also recommended that cameras operating in this mode have unwanted light sources carefully blocked/masked during calibration in order to prevent excessive USB bus traffic.

Post Reply