I just played the wmv without PPT and I saw that the white
background is gray.

The original video is a .mov and the background is white.


I imported it in Sorenson Squeeze do make a .wmv. and the background
turns to gray.

So, do you know which type of codec I need?
In sorenson squeee, I used wm video v9.

Or maybe it's not the good compression?

Thanks for your help....

Try looking for some other free convertors, until you find one that doesn't grey out the background!

Like:

Here
or
Here