1. A method of processing a video stream, comprising: processing the video stream to detect a start of a first motion event candidate in the video stream, wherein processing comprises: obtaining a profile of a motion pixel count for a current frame sequence in the video stream; in response to determining that the obtained profile meets a predetermined trigger criterion, determining that the current frame sequence includes a motion event candidate; identifying a beginning time for a portion of the profile meeting the predetermined trigger criterion; and designating the identified beginning time to be the start of the first motion event candidate; and in response to detecting the start of the first motion event candidate in the video stream, initiating event recognition processing on a first video segment associated with the start of the first motion event candidate.