Example 1 (continued)

Clearly this m-CQ includes the following operations (or manipulations) over the Video multimedia streams:

1) Tumbling Window: a window of size 30 sec, and step 30 sec should be first defined. Over the previous window, there is a filter that filters out the frames not coming from the entrance or exit locations. Or in data base language, a Select operator with predicate set such that the location_id field equals to that of the entrance, or that of the exit sites.

2) For all frames that go through the above 2 operators, some mtb1 or mtb2 should be utilized to detect weapon objects. This is considered a transformation operator.