Welcome new user! You can search existing questions and answers without registering, but please register to post new questions and receive answers. Note that due to large amounts of spam attempts, your first three posts will be manually moderated, so please be patient.
We have moved to a new forum at http://jevois.usc.edu, please check it out. The forum at jevois.org/qa will not allow new user registrations but is maintained alive for its useful past questions and answers.
Welcome to JeVois Tech Zone, where you can ask questions and receive answers from other members of the community.

Finding difference between the image grabbed and serial message sent to my host computer in DemoARtoolkit program?

0 votes

Hi Team,

I am trying to find the time difference between grabbing an image, detecting a marker and sending the serial data((parsing serial data python)) to a host computer over usb.

Since the image is grabbed on the jevois camera and serial is received on the host computer, I am pretty confused about how to measure this delay.

Can someone please give me an insight into this problem?

asked Jan 28, 2019 in Programmer Questions by ashwinsushil (240 points)
edited Jan 29, 2019 by ashwinsushil

1 Answer

0 votes
Could you put timestamps in the image and the serial data? You'd at least be be able to read the timestamp in the image. It might give you some insights.
answered Jan 29, 2019 by Tcornall (700 points)
Yeah, that sounds like a plan to start with. Thanks man ;)
Also see parameter "serstamp" here: http://jevois.org/doc/UserSerialStyle.html

You would need a way to synchronize the clocks between JeVois and CPU. I don't know much about the internals of how NTP (network time protocol) works, but that's how we get all the computers on our cluster here in sync, despite unpredictable network latency. You can't use NTP directly on JeVois since there is no network stack. But maybe the idea of how it measures latency could be ported to your own code.