Not sure if this is the best way, there are usually a few ways of doing anything in vegas, but this is how I just did it.

Put a track above the video in question. Fill it with a clip using the insert solid colour tool (in 'insert' menu in 'generated media'), select black as the colour. Then select the 'event pan/crop' icon on that clip. At the bottom of the window that opens, tick 'mask'. Use the 'ink pen' tool to draw a box around the clip (decrease the level of the track to make this easier, you can then see the track below). Put the level back up, now insert the 'gaussian blur' effect onto that track and only the part selected ny the mask will be blurred.

Edit, also you can use the track motion tool on the mask track to keyframe in any movements needed to follw the plate.

Hope that helps, if anything isnt clear there post again and I will have another go.

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I have two prejudices - I am anti HDV for consumer camcorders, and I eat mooks who claim to be pro wedding vidders and ask dumb questions.

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