How to record time - not duration

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How to record time - not duration - of stimulus onset?

How to record time - not duration - of stimulus onset?

Author	Message
juhaso	juhaso posted 10 Years Ago ANSWER Post Details Share Post
Group: Forum Members Posts: 2, Visits: 13	Actually that does not help much. If I find script.currenttime script.elapsedtime 12:13:23 41291 12:13:33 51391 in my logfile, I know that the trial startet at second 23 and lastet for exactly 10 seconds. However, I don't know exactly when it started. That's to unprecise to sync it with a videorecording of 30 fps which records a frame every 33 ms. My workaround-solution is to wait for a "full" second: ------------------------------------ ### Start experiment-block if second is "full" ### (Inquisit 3.0.6.0) <expt> / subjects = (1 of 1) / blocks = [1=loopfullsecond] </expt> <values> / beginningSecond = script.currenttime </values> ######################### ### "full second" loop ######################### <block loopfullsecond> / branch = [if (script.currenttime > values.beginningSecond) block.experiment] / branch = [if (script.currenttime == values.beginningSecond) block.loopfullsecond] </block> ######################### ### Experiment starts ######################### <block experiment> / trials = [1=experiment] </block> <trial experiment> / stimulustimes = [0 = experiment,currenttime1,currenttime2,elapsedtime1] / timeout = 5000 </trial> <text experiment> / items = experiment / valign = center / halign = center / position = (50%, 50%) / txcolor = (0,0,0) / fontstyle = ("Arial", 5%) </text> <text currenttime1> / items = ("Script start second: <% values.beginningSecond %>") / position = (50%, 60%) / halign = center </text> <text currenttime2> / items = ("Current time: <% script.currenttime %>") / position = (50%, 70%) / halign = center </text> <text elapsedtime1> / items = ("Elapsed time (should be lower than 1000): <% script.elapsedtime %>") / position = (50%, 80%) / halign = center </text> <item experiment> /1 = "Experiment starts" </item> ------------------------------------ The script itself seems to need about 32ms to get up and running on my machine (measured with a very simple script and script.elapsedtime). That's an offset of one frame and acceptable/assessable for me. Nevertheless, a more precise timestamp would be very useful ;-)
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Dave	Dave posted 10 Years Ago ANSWER Post Details Share Post
Group: Administrators Posts: 13K, Visits: 103K	No. The currenttime property does not provide milliseconds. elapsedtime, however, is provided in milliseconds, so if need be you could conceivably combine the two (using math via expressions).
	Like 89
juhaso	juhaso posted 10 Years Ago ANSWER Post Details Share Post
Group: Forum Members Posts: 2, Visits: 13	Thank you for the very nice possibility, to include a timestamp of the inquisit-events in the logfile via <data> / colums =[...,script.currenttime,...] </data> However, to synchronize inquisit-events very accurately with an externally recorded video (with timestamps) it would be very useful to have a inquisit-timestamp including milliseconds, e.g., in the format hh:mm:ss:xxx where xxx are the milliseconds. Is there any possibility to have that?
	Like 102
Dave	Dave posted 10 Years Ago ANSWER Post Details Share Post
Group: Administrators Posts: 13K, Visits: 103K	You'll want to make use of the applicable 'currenttime' and/or 'elapsedtime' property to record a timestamp /ontrialbegin, log that to the data file and then add stimulusonset to the timestamp to approximate absolute starting time for the given stimulus.
	Like 97
marieke_01	marieke_01 posted 10 Years Ago Topic Details Share Topic
Group: Forum Members Posts: 1, Visits: 1	Hello. We want to supervise by video if a participant has really observed the presented stimulus. Therefore, we need the time, when the stimulus was presented. With "stimulusonset" it´s only possible to record the milliseconds after the trail began - thus, a kind of hold-up effect control. But we need the time - in terms of time of day (10:12:13) or the milliseconds, counted scine the beginning of the whole experiment. Who can help? Thank you, Marieke Tags stimulus onset time recording
	Like 97