Playing a video in two players at same time - why they look so different?

[snowcrash]

There's something strange I noticed and I'm just curious as to why this happens. If I play a video in Zoomplayer and then open a second instance of the same video in another window, the first one that was opened looks much better... it's brighter with more vibrant colors. I see the same thing even if I use two different players, like for example WMP and Zoomplayer. Whichever one I open first always looks better, no matter which media player.

Another thing I noticed is that with the one that was opened first and that looks better, if you drag the media player there is a lag with the actual video picture moving. It's as if the video floats around on it's own. Whereas with the one opened up second, the video is just statically bound to the media player when moved around.

I'm thinking this behavior has to do with something I've seen mentioned before in regards to PC video... "overlay". But I'm just guessing because I don't really understand the concept.

Can anyone explain what's going on here? Also, what started all this is I was trying to compare two videos side-by-side. Is there any good way to do this so that both videos are displayed the same way? Is there some sort of mediaplayer that will play two videos side-by-side or in a split-screen?

thanks

[Neo Neko]

Your video card only has one video overlay. So if it can not share the overlay then only one aplication at a time can use it. The one using the overlay would tend to look smoother and brighter while the one being played back in software will be choppier and darker.

[mf]

Try using VMR or software rendering. Both should look the same.