Patent Document ID: 10018703
Application ID: 13613174
Patent Status: 1

Claim One:
1. A vector-based stop detection method for enforcing traffic signal compliance, the method comprising: receiving video data from a surveillance camera; defining a target area in the received video data; dividing a current frame into a number of blocks; computing a displacement for a block between a reference frame and the current frame and describing the displacement of the block as a motion vector; defining a cluster as a group of one or more connected motion vectors having a length meeting or exceeding a first vector length threshold and classifying a block having a motion vector meeting or exceeding the first vector length as an active motion block; in response to a number of active motion blocks in the cluster meeting or exceeding a cluster size threshold, classifying the cluster of motion vectors as belonging to a vehicle; tracking a position of the cluster across two or more video frames; monitoring the length of motion vectors of the cluster in the two or more video frames and reclassifying any motion vector that no longer exceeds the first vector length threshold as not an active motion block; in response to the cluster transitioning from having the number of active motion blocks meeting or exceeding the cluster size threshold to having fewer than a second number of active motion blocks, classifying the cluster as being inactive; in response to the inactivity of the cluster persisting for a predetermined duration, classifying the vehicle as being stationary; in response to the activity of the cluster persisting in the target area, classifying the vehicle as not being stationary and transmitting a signal and compressed pixel data to a second device.