One of the vendors at Moodle Moot Au 2010 was Echo 360 with their Lecture Capture System. This grew out of Lectopia (or iLecture System) developed at the University of WA. It happens I had seen an early version of this system in use at the UWA's Albany campus, when a consultant for government.
Echo 360 now offer custom hardware for lecture theatres, called their "EchoSystem Capture Appliance". This takes VGA from a computer, along with video and audio and digitises it all. The files are sent to a central server, incorporated in the LMS and if needed, Podcast. Echo 360 had a demonstration unit with a transparent case on display. I suggested offering this model to the Department of Defence and other security organisations, as it would allow the unit to be easily inspected for tampering.