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Pavlolvia constraints when using many large video files?

Hi Everyone-
We’re new to online experiments. In our experiments, we are planning on presenting many (~200) large video files (~10mb). We can easily do this using PsychoPy, but are folks aware of any constraints on doing this online via Pavlovia? I believe that Pavlovia loads everything into the browser’s memory before the experiment starts. Besides this taking quite some time for our experiment, should we anticipate any other problems?
We just wanted to find out before we tried setting it up online.
Thanks so much! And I apologize if this information already exists in the forum.
-Larry R.

Hi Larry, thanks for getting in touch. In theory no, that is permitted but in practice, right now, we would struggle! The server is pretty full and due to move next Sunday to a new more powerful machine, so if you could hold off uploading your full study until then it would be great!

Long term @apitiot and I are going to have to work out what to do about large projects. If lots of people need >2Gb per project then we could be in trouble. So we might one day introduce either caps, or discouraging charges for large projects.

In the meantime, yes there is also the issue that the study will take a while to start for the participant. Again we will look at this in the long term, whether to allow a study to start still while downloading stimuli. It’s possible but we don’t want the possibility of a study going into “buffering” halfway through on a slow internet connection, hence the current strategy.

Thanks so much, Jon-
This is really useful information, and I am glad that our projects could work in principle. We will absolutely wait until next Sunday to try a full upload. As we try things out, I’m happy to share our experience on how the stimulus pre-loading strategy works.
Thanks for creating and supporting such a great set of projects which have become so useuful for so many of us at the current time.
-Larry