Just before an hour i screen captured and encoded a video (using Microsoft Expression 4) and then cropped that video using Format Factory and later uploaded on YouTube (.mp4) format.
Original video length : 10 Mins 08 Secs After cropping : 8 Mins 35 Secs Before uploading to YouTube : 8 Mins 35 Secs After uploading on YouTube : 17 Mins 11 Secs
Size of my video is getting almost double after uploading.. ha ha funny ;)
What's wrong in this? Have I made some mistake in converting/cropping my video or it's a YouTube problem?
I've uploaded some screen shots for a clear explanation.

