Millisecond Forums

Inquisit & webcam

https://forums.millisecond.com/Topic16697.aspx

By eacschwille - 7/14/2015

Hey,

in my experiment, I plan to record the facial expression of participants (e.g., with a webcam) while they watch several short videos. Is it possible to tell Inquisit to start recording at a certain point, stop recording after a certain time, and store the recorded video in a certain location on the server with a particular name (e.g., including a running number)?

Sorry, if this question is very novice. So far, I've only been programming rather simple surveys and experiments.

Thanks!
By Dave - 7/14/2015

Inquisit by itself has no means to interface with a webcam at present. What you can possibly do is attach the webcam to a 2nd computer and have Inquisit send signals to that 2nd computer via the parallel or serial port. You would then have to write a small program that runs on that 2nd computer, receives the signals, starts and stops the webcam recording accordingly and uploads the video to some location. This, of course, can only work in a lab setting, where you have full control over all devices.

Hope this helps.
By eacschwille - 7/15/2015

I'm planning to run the study in the lab, but I don't think I will have two computers available for each participant. We'll see how it works out. Thanks for the quick reply, though!
By Nathalie - 3/30/2016

Hi,

I am also interested in this issue.
We are running an experiment, where one of the tasks would be recorded.
We would like to let the webcam record only that task and then turn off again.

Is there any other solution that might work (besides the one suggested above).
We are currently already using the parallel port to send signals between inquisit and our physiological system (biopac mp150).
This only works when using a single parallel port (and no combined serial and parallel port addition to the computer), so we cannot use a port anymore to send signals to another computer.

Would there be any other way to solve our issue? 
We thought about letting participants turn on/off the webcam themselves at the right moment, but this does not seem possible either, because then they have to stop the inquisit experiment in order to access the webcam software.

Hope someone has another suggestion for our issue.
Thanks in advance!

By Dave - 3/30/2016

No, as best as I can tell, there is no other way, I'm afraid.