Image manipulations on video in Windows

[changt...@gmail.com]

Hi

The desktop application, on which one video is playing.
(Video is collection of frames) On each frame, user selects some area
on the frame or
marks some points on that frame.
How to get the selected area on frame?
How to get the points marked by the user on the frame?
How to do this?

Is this is possible in Windows?
Is it possible in MFC, Win32, C# or VB?
If possible what are the API's to use?
Plase give me some sample source code to do this.

Thanks in advance.
Kavita