video display problem in MediaLab v.2012 (case 11606)

I'm running a CRM experiment to collect some online rating for a series of video clips. My clips are all in .wmv format and my initial parameter setting was (w900,l80,t120) for all clips which worked perfect on a desktop computer with a 4:3 monitor. But because I need to run the real experiment on wide-screen laptops, I changed it to (l.2,t.3) make the video display a better fit on the wide screen without having to try out different number for the dimensions. But the problem started which was that sometimes some (not all) clips would show in a teeny tiny window on the very top of the black display area in the center of the screen. I did test run on several different laptops in our lab (all of same brand, model, and configurations) and the problem occurred randomly, each time with a different clip and on a different computer.

I changed everything from the percentage format (l.2,t.3) back to the (w,l,t) format but the problem persisted, although it seemed to be occurring at a less frequency, only one out of the total 17 clips. Yesterday my professor advised me to try using (w-2) for all clips. That fixed the problem but temporarily but it came back later today. Still, just one clip with wrong display throughout the entire experiment.

Due to the randomness of the problem I don't know how to trouble shoot it. I had literally tried every different parameter combinations suggested in the manual but nothing seems to make the problem go away. What's the source of the problem??

Take a look at the forum thread at this link and try installing the [I]ffdshow tryouts[/I] codec:

[URL]http://www.empirisoft.com/support/showthread.php?8064-Issues-with-displaying-video-(case-3360)&highlight=MediaLab+video[/URL]

Thank you for your suggestion. I will give it a try.

Do I need to do anything or change anything in MediaLab after the codec is installed?

I don't think so. You should just open MediaLab and run the files that you have.

Hi ggcana,

Did you ever get a chance to install the codec and see if it helped display your videos?

[QUOTE=jason_reed;20429]Hi ggcana,

Did you ever get a chance to install the codec and see if it helped display your videos?[/QUOTE]

I did, and the codec seemed to help at first. I didn't have new incident with display problem for a couple of days and then it returned.

The settings of the codec looked very complex and we just used the default settings. Not sure if changing any of the settings would help eliminate the problem... but overall, the video display issue occurred at a low rate: about 10% of the subjects were affected and with each person, the issue happened to no more than one video clip during the entire experiment, which contained 16 video clips plus 1 practice clip. So I didn't lose too many data due to this technical issue.

Thank you for the follow-up. A new experiment will start soon. I will let you know if I have more to report.

Just checking in to see if you had anything more to report :)

[QUOTE=jason_reed;20547]Just checking in to see if you had anything more to report :)[/QUOTE]

Thanks for checking. I just finished collecting STRT data using the same stimuli last weekend. The teeny tiny display window did occur twice with my subjects, both during practice session. Once I caught it in time and immediately restarted the computer. The other time I didn't know until the subject reported it after he finished watching the videos---but he confirmed that it happened only during one of the practice videos. So it appeared that the "real" experiment session went well with all participants without any visual display issues with any of the stimulus clips.

Thanks for the update. Did you happen to notice if the two incidences you most recently encountered were the same as the previous ones or were they different in any way?

[QUOTE=jason_reed;20569]Thanks for the update. Did you happen to notice if the two incidences you most recently encountered were the same as the previous ones or were they different in any way?[/QUOTE]

They appeared to be the same as far as I can tell.