Patent ID: 9665776
Date: 2017-05-30
CPC Classifications: G06K,G06T,G08B,H04N

Claim:
1. A 2D occupancy system for determining a position of a user in an environment, the system comprising: a host device and a plurality of event detection devices connected through a network, at least one of the plurality of event detection devices comprising a low resolution detection device with a resolution of about 4000 pixels in total or below, each event detection device having a viewing angle, wherein parts of the environment covered by the viewing angle of a single event detection device and parts of the environment defined by an overlap of the viewing angle of any event detection device with a viewing angle of at least one other event detection device form a plurality of polygons in the environment, the host device comprising an input port configured to receive event information related to presence of users in the plurality of polygons in the environment from the plurality of event detection devices, and a processing unit that determines the position of the user in the plurality of polygons in the environment from the event information from particular event detection devices at a same time-stamp, wherein an event detection device comprises an array of photosensors, a storage unit connected to said array for storing a reference frame of pixel values in which each pixel value is indicative of light energy received at a particular photosensor at a specific time, a correlation device connected to said array and to said storage unit that correlates an arrangement of said pixel values of said reference frame with at least one sample frame of pixel values formed in response to light energy received at said array subsequent to said specific time, and a computer, responsive to detection of correlations by said correlation device to generate an attitudinal signal representing optical flow of pixel values of said at least one sample frame relative to said pixel values of said reference frame, said attitudinal signal thereby representing a direction and/or size of movement of the user in the plurality of polygons in the environment.