Oddside

Hello everyone! I would like to seek your advice for a special setup with a simple single-CCTV setup, but a special reporting requirement: I would like to be informed when there is NO activity registered by the cam during regular business hours. Hence, CCTV would record continuously during business hours and once it records a prolonged time without any activity (approx. 15 minutes), the time with no activity + the previous 5 minutes shall be processed and sent in a email report. Would you know a hard/software setup that offers this special requirement? Cheers, Oddside