I Do Detect Comms HELP NEEDED

Dear Jere Jones!

My job is to monitor regional comm inserts via "good" old analog CATV.
I rec broadcast non-stop on a CCTV system and then have to find those comm lead-ins n outs!
The ? is whether it's possible to postprocess those mpeg-files to get info showing when those comms took place?
It would be fine to make it in real-time!
Among the variety of PVR (Sage, GB, МСЕ, Tivo ) what would do best?, OR perhaps I dont even need any for I've already got mpegs recorded to run postprocess solely?

Stands to reason, video semantic analysis has always been a hard nut to crack but perhaps there's a way to mend the matter?

PLEASE HELP for my eyes are already worn out because of RSI !!

Respectfully,
Be lucky in life as well as in the bullfight against comms!!