Does a flash movie know how big it is on the screen?

Does a flash movie know how big it is ont he screen?

I want to be able to check if the flash movie (or projector) is not playing at it's intended size.

Something like this

goodWidth=640;
goodHeight=480;
if(actualDesktopWidthUsedByMyMovie!=goodWidth ||actualDesktopHeightUsedByMyMovie!=goodHeight){
//do something here based on the actual amount of desktop space used by my movie
}