Timestamps of videos for integration with facereader

Builder
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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

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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

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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.

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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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