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Problem with display of movie stimuli on Pavlovia

Movie stimuli are not displayed in the Chrome’s window on Pavlovia although the sound is played back.
Changing the window size while the sound is played, I can watch the movie (but the next stimulus is not displayed until the window size is changed again).
I confirmed this problem in both Mac and Windows.
Does this concern Chrome rather than Pavlovia?

I would appreciate if someone could answer this question.

Hi There,

Please could you share the URL to your project? I am not aware of an issue presenting movie stimuli on chrome at the moment. by “changing the window size” do you mean changing the size of your browser window during the experiment?

Thanks,
Becca

Hi Becca,

Thank you for your reply.
Sorry, it may be difficult to share the URL because I made a contract with the people appearing in the movies not to make the stimuli public. If I share the URL to my project, can everyone see the stimuli? (I do not know the details of the sharing system.)

by “changing the window size” do you mean changing the size of your browser window during the experiment? So, the stimuli seems to be played on the back.

Yes. When I change the size of the browser window, the movie stimuli is displayed.

Hi There,

That is completely understandable so do not worry about sharing. Based on what you describe there that does sound like a browser issue, but it is a new one I haven’t heard before. Do you have the movie stimulus set to be specific dimensions in the size parameter?

Thanks,
Becca

Hi Becca,

Thank you so much!

Although I tried setting the size parameter for “norm, (2, 2)” and “pix, (1920, 1080),” both settings did not work well.

When I tested using another project including a small number of movie files, the movies were displayed in the browser window without problem.
So, this problem may concern the number of mp4 files in my project because there are about 100 files (about 350MB) there (however, even when I set the experiment in the project to display a small number of stimuli, the trouble occurred).

Thank you.

In terms of the settings “not working well” was it that the movies appeared a bit of an odd dimension? - did you get the same error of not seeing the image/movie until you adjusted the size of your browser window?

It is good that you have tried using another project, if you fork that project and adapt it to use your movie files do your movie files present correctly? (this will help narrow down if it is likely to be the movie files or the parameter of the movie component in you psychopy programme :slight_smile: )

Thanks,
Becca

In terms of the settings “not working well” was it that the movies appeared a bit of an odd dimension? - did you get the same error of not seeing the image/movie until you adjusted the size of your browser window?

I got the same error as what I have explained in both settings.

It is good that you have tried using another project,

Sorry, my explanation lacks some pieces of information.
The test experiment is the same project from which I got the error. I tested it with a small number of files uploaded before the other files were uploaded there. In that time, the experiment worked without any problem in Chrome.

After I sent the previous reply, I made another project including a small number of files again and tested the new experiment, but I got the same error in this time.
I tried the experiment in other browsers (Microsoft Edge, Firefox), but the results did not change.

hmm interesting - do you get any error messages ? (you can open the developer tools as described here https://docs.google.com/document/d/13jp0QAqQeFlYSjeZS0fDInvgaDzBXjGQNe4VNKbbNHQ/edit)

Hi There,

Had a further look into this one as also managed to replicate in chrome!!

The fix seems to be making it so the movie start time is not 0 seconds. For me setting it to 1 second enabled the movie to play with browser in full screen mode.

Here is the gitlab project with the demo to download https://gitlab.pavlovia.org/lpxrh6/multiplemovie.

I hope this solves your problem!
Becca

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meew that didnt solve my problem :frowning: i tried setting movie start time to 1, at first iteration it works fine. but at the second iteration, it doesnt play anything at all.

Dear Becca,

is it possible for you to share the url or this test experiment? so that I can compare it with mine.

thanks, tutku

Hi Becca,

Thank you very much!
Setting the start time to 1 second in my experiment as you said, I did not get that error and the movies were displayed without problem!

Is this problem a bug in Pavlovia?

Hi tutku,
You can access and download the project using the link above.
Thanks,
Becca

Hi Ninet,

Please that solved the issue for now! This does indeed look like a bug, but our developers are now aware :slight_smile: Thanks!

Becca

Hey @Ninet, @tutku, @Becca, as it happens the issue is with one of our external code components or dependencies, PixiJS, but a fix is on the way. For the time being, please refer to this fork on how to edit index.html to link to the latest version of PixiJS. You would not need to wait before calling for the video to play then.

That index.html is of course automatically generated and overwritten each time you export from the Builder! So some care is required to keep the edit in place, but again only for the short while it will take us to patch things up on our end. I hope that helps some. Please let me know if you come across any more issues getting your study to run as expected, x

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