Crop live video stream

I have a streaming vide开发者_开发百科o that is displayed on a web page through a flash player from an external source. This video has a huge border that I would like to crop out before displaying. How can I alter the feed in real time before showing it to the user, such that the resulting video has its border removed?

Thanks.

You don't need to crop the stream, you can simply apply a mask to the video object in the desired dimension (size of stream without borders). You may have some difficulties in fullscreen mode. Also you may resize the video object in that way, that it fills the area where you are displaying the stream. This needs some math, but should be manageable.

You can use FFMpeg.exe to crop video. Also if it's very big, you can resize video with it.