Constant Background Image (case 10428)

Is there any way to display a background image constantly across all trials without having a momentary gap in between trails?

Thanks!

Hi osuncogdevlab!

Could you please be more specific about what kind of delays that you are experiencing when using DirectRT? It might also help if you had an example of the input file showing these delays that you could send to me. You can either attach it to you reply to this message or send it directly to me at [EMAIL="support@empirisoft.com"]support@empirisoft.com[/EMAIL]. If you send it to that email address, please include case 10428 in the email subject line.

Hello,

The input file and the style file have been attached. DirectRT presents the background image, then shows the stimulus, but in between trials the entire screen goes white before the background image reappears. I hope there is a solution.

Thanks!

P.S. We are also having trouble displaying PNG files. Is there an easy way to accomplish this?

Thanks for sending me the input files. Try making two changes to the input file and see what happens. First, change the display time for all the WADBackground stimuli to 0 and run the input file. If that doesn't work, change those display times back to 1000 and remove the clear500 command from the time column of the DOT1 stimuli and run the input file. Let me know if either of these changes stops the white flash from happening.

I will also look into using .png format for image files, but could you use .bmp formatted files instead? DirectRT should be able to easily handle any .bmp files.

We have tried both of your suggestions, and removing the clear function seems to work better. However, we are still experiencing a 20-50ms flash in between trials. Our background being 1920 x 1080, this is still quite problematic. Might you have any other suggestions?

In regards to the BMP and PNG files. When we export a file as BMP from GIMP the background remains transparent, but will not play in DirectRT. We must open the file with Paint and re-save the image (we must do this with all images from GIMP). At this point, we lose the transparency we desire.

How can we create an image with a transparent background that will be compatible with DirectRT?

Would you mind sending me copies of the images and other external files that you use with this input file? I'd like to try running it on my copy of DirectRT.

Also, what version of DirectRT do you have (ver.20xx.x.xxx)? You can find the full number by opening DirectRT and selecting Help > About DirectRT.

We are running on Version 2012.4.0.160. I have attached everything here.

Thanks!

Have you tried seeing what happens if you change the values of the Back and Colour fields in styles 1 and 4 of the StyleFile to 0?

The screen still flashes but now it flashes to a black screen instead of a white screen.

We are having other issues with DirectRT, so we will move the stimulus question to the troubleshooting thread.

Take a look at this forum thread:

[URL="http://empirisoft.com/Support/showthread.phpt=141&highlight=trial+interval"][COLOR=#0066cc]http://empirisoft.com/Support/showthread.phpt=141&highlight=trial+interval[/COLOR][/URL].

The link gives me a 404 error

I've tried a few other options and talked to a programmer. You will see a flicker anytime that you have more than one row in a DirectRT input file. Whenever one trial ends in DirectRT, it then compiles all of the stimuli in the next trial before moving on to it. Thus, a brief flash to accompany this set up is inherent to how DirectRT works.

That being said, you may want to consider if setting up your input file so that all of your stimuli appeared in a single row may serve your purposes. After DirectRT loads all of the stimuli for that single trial, it may prevent any flicker from happening between presentation of stimuli.

Thanks for following up. Putting 300+ stimuli, with each stimulus requiring a response, on the same row is not an option for us. We decided to remove all of the details from the background and go with a solid color background. While not as interesting for kid participants, it did take care of the flickering. Thanks again.

Glad to hear that you found a solution.