Timestamps of videos for integration with facereader

OS (e.g. Win10): Win11
PsychoPy version (e.g. 1.84.x): 2022.2.4
Standard Standalone? (y/n) If not then what?: y
**What are you trying to achieve?:

Hello everyone!
I am trying to set up an offline experiment, in which I present videos to my participants through Psychopy, and I want to collect information about their facial expressions using Observer XT/Facereader. My plan is to posteriorly integrate the data of both software (offline; after data collection) but for that, I need timestamps of the starting and end of each video in Psychopy.

What did you try to make it work?:
I am using globalClock.getTime() on each frame and with that get the information of the starting time.

What specifically went wrong when you tried that?:
I also need to know the exact time when the presentation stopped. (FYI, duration is set to infinite). Can anyone help?

Many thanks in advance,
Mariana

Hi Mariana,

Your video component should have a column in your data output e.g. movie.start - do you see that in the data?

Incidently - it might be of interest to you that for online studies you can already detect and save facial expressions in psychojs - here is a demo and associated code.

Becca

Hi @Becca !

I do see movie.start in the .csv file when using the globalClock.getTime() command. But I also need the information about the time when the presentation of the video stopped. Since I did not specify a duration for the stimulus, I expect it to end movie.start + 180 seconds (which is the duration of the movie). Nevertheless, considering possible delays, I wanted to be sure about the precise moment it stopped showing the clip. Can it be done?

Thank you for the materials on psychojs facial expressions analysis, I will take a look.

To save the current clock time at any point try thisExp.addData(‘ClockStart’,data.getDateStr())

For online use, this needs to be manually translated to:
util.MonotonicClock.getDateStr()

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