when the user log on(switch on) the system Capturing a Desktop screen until the user log off(shutdown) the system using Windows services?

Question

Hi all,

when the User log on the system we have to start capturing the desktop screen until the user log off or shutdown the system and save in  the database.

Have to achieve using the service concept? such as windows services.

It should capturing the desktop screen in windows 7.

Please help.

Thanks in advance.