I'm trying to present videos in my experiment but I've been having trouble custom define the display ratio of the video box. No matter which dimension I entered, the program simply displayed them as a fixed size rectangular. This seriously distorted my video image.

Strangely when I tested the program on the demonstration videos along with the script that was downloaded from here, I was able to show them at normal ratio and was able to change it whichever way I want.

Then I copied one of my videos and put it in the example stim folder, it worked fine too. That makes me sure that there was nothing wrong with my video images. But when I put all of my videos in the Stim folder and run an edited script, it simply wouldn't work anymore.

Now I really have no clue why this is happening.
The ratio I was trying to define is sth like:
_**.avi (458×539)
_**2.avi (410×561)
_**7.avi (473×566)
_**7.avi (452×540)
Please help me!! Thanks