how can I blur part of video?

I want to blur a small rectangular region of video. are there any free tools for this? how would I do it?

thanks a lot.

 

You could use Virtualdubmod's Logo filter. It will place a still .bmp image (e.g. a cropped, then blurred, screen grab from your video) over any rectangular portion of the video.

There's probably easier ways with commercial software, but that's the first thing that came to mind with just freeware.

 

thank you greatly for the reply. I will try to find easier solutions first. I appreciate your help. Thank you again

 

I used the "logoaway" filted on virtualdub... just in case other's are wondering.