Issue loading mp4 file in MWorks

Support
1

Hi Chris,

I’m running Mworks version 0.8 on a Mac OS 10.14.3, and I’m having trouble loading multiple mp4 videos (I can load up to 400 videos, but if I load say 500 or 600, it gets stuck — loading time > 30min).I use a range replicator to load my videos.

I’ve attached the MWorks output below. Do you have any guessed on why this might be happening? Any clues on where to look will be helpful!

Thanks in advance!

Sachi

2

Attachment: MWorks_output.txt (56.4 KB)

3

Hi Sachi,

From the console output, it looks like the experiment begins to load normally but never completes. Is that correct? Does the default gray background appear on the stimulus display before things get stuck? If yes, then it’s possible you’re running out of RAM while loading the videos, and you may need to use explicit loading and load and unload individual videos as needed. About how large is each video file?

Alternatively, if loading gets stuck before the gray background appears, then you’re probably running out of RAM while copying the video files from MWClient to MWServer. Michael has run in to this issue on iPad’s. Unfortunately, I don’t have a good solution for this problem yet.

Cheers,
Chris

4

Hi Sachi,

Were you able to resolve your video loading issue? Do you need any assistance implementing workarounds?

Chris

5

Hi Chris,

Sorry for not getting back. You were right about running out of RAM (each video is ~200kB). Our workaround has been to split the 600 video set into two and run them separately. (Presenting all 600 videos as a sequence of image frames also works, so in the future, if I have a ‘big’ video set, I’ll revert to that).

Thanks for checking in,—and for your help,—Chris!

Sachi