Millisecond Forums

Task runs fine locally, but when uploaded, image stimuli take excessive times to appear

https://forums.millisecond.com/Topic30865.aspx

By Rob Morton - 2/19/2021

Hi all,

I've just been working on some modified versions of the "Mental Rotation task - English" and have uploaded it to Millisecond.com.  The task runs perfectly on my PC locally, but the online version is subject to an unacceptable delay of around forty seconds after the last instruction page, before the first .JPG stimuli appear.

Is this possibly a transient internet problem due to bandwidth or slow broadband or a similar problem, or could it be some error in the script?

These are the tasks:

https://mili2nd.co/dcyb
  
https://mili2nd.co/ecyb
  
https://mili2nd.co/fcyb
  
https://mili2nd.co/gcyb

I'd be grateful for any help or advice.  Thanks for your time,
Rob
By Rob Morton - 2/19/2021

Hi Rob,

There is nothing in your scripts that would tell Inquisit that it needs to download any images upfront. This is not a problem when you run the task locally on your computer, because the images will already reside there. Not so when the task is online. Thus, Inquisit then has to reach out to the server and download images while the task is already running. To prevent this, add a <picture> element to the scripts that references the images <item> element.

<picture downloadimages>
/ items = images
</picture>

Inquisit then knows that it has to download image files, will download them upfront, and that will eliminate any delay at runtime.

Regards,
-David
By Dave - 2/19/2021

Rob Morton - 2/19/2021
Hi all,

I've just been working on some modified versions of the "Mental Rotation task - English" and have uploaded it to Millisecond.com.  The task runs perfectly on my PC locally, but the online version is subject to an unacceptable delay of around forty seconds after the last instruction page, before the first .JPG stimuli appear.

Is this possibly a transient internet problem due to bandwidth or slow broadband or a similar problem, or could it be some error in the script?

These are the tasks:

https://mili2nd.co/dcyb
  
https://mili2nd.co/ecyb
  
https://mili2nd.co/fcyb
  
https://mili2nd.co/gcyb

I'd be grateful for any help or advice.  Thanks for your time,
Rob

As far as I can see, the issue with these scripts is the same as e.g. here:
https://www.millisecond.com/forums/FindPost18088.aspx

The same solution, i.e. adding a <picture> element that causes the image files to be downloaded up-front, applies. In your case, that would be something like

<picture downloadimages>
/ items = images
</picture>

The <picture> element above doesn't have to be used anywhere else in the script, it just needs to be there, and that will be enough to trigger the download of the files prior to startup.
By Rob Morton - 2/19/2021

Thankyou again David, your help is appreciated.  :)