1. A computer-readable medium comprising software for monitoring a point of sale (POS) transaction, which software, when executed by a computer system, causes the computer system to perform operations comprising a method of: receiving non video data regarding the point of sale (POS) transaction; generating POS primitives based on the received non video POS data; receiving video data regarding a corresponding POS transaction; generating video primitives based on the received video data; and inferring an exceptional transaction based on a corresponding exceptional transaction rule and at least one of the generated POS primitives or video primitives.