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ArUco detection: USB data slows down when moving camera

0 votes

I am using the built-in ArUco model to detect 3D pose.

I used the following setting in the init script:

setmapping2 YUYV 320 240 30.0 JeVois DemoArUco
setpar serlog None
setpar serout USB
setpar serstyle Normal
Then, in my Mac terminal, I use 'screen /dev/tty.usb...  115200' to monitor the data, while the camera is connected over USB.

When I expose the camera to an ArUco marker (while the camera is not moving), the pose estimate are perfect and coming out on the terminal screen in a steady rate. However, once I start moving the camera, even slowly, around the marker, the rate of data output on the terminal screen come out with a significantly reduced rate!

What could be the problem?!
asked Dec 28, 2017 in Hardware Questions by Mzahana (170 points)

1 Answer

0 votes
A previous similar case involved a connector that was a bit loose, somehow not enough for the camera to completely disconnect but enough to create transmit errors. So you could try to securely mount the camera and cable connector and try again. Or try to keep the camera fixed, and move the aruco instead.

Or, maybe the ArUco algo runs slower in the presence of motion blur. Try first by using the video mapping with USB output. Check the processing fps at the bottom left of the video, does it slow down when things move? If so, you could try to switch to manual exposure and gain, then aim for a low exposure and increase the gain accordingly until things get too ugly noisy. The low exposure time should minimize motion blur.
answered Dec 30, 2017 by JeVois (46,580 points)