Action detection during image tracking

A method, comprising:

• receiving an image feed comprising frames of top-view images generated by a sensor, the sensor positioned above a rack in a space and configured to generate top-view images of at least a portion of a space comprising the rack;
• detecting an event, wherein the detected event is associated with a portion of a person entering a zone adjacent to the rack;
• in response to detecting the event, determining that a first person or a second person may be associated with the detected event;
• in response to determining that the first or the second person may be associated with the detected event, storing buffer frames of top-view images generated by the sensor during a time period associated with the detected event;
• determining, using at least one of the stored buffer frames and a first action-detection algorithm, whether an action associated with the detected event was performed by the first person or the second person, wherein the first action-detection algorithm is configured to determine whether the action associated with the detected event was performed by the first person or the second person by:
• iteratively dilating, from an approximate head height of one or both of the first person and second person toward a floor of the space, a first contour associated with the first person at least until the iteratively dilated first contour extends into the zone adjacent to the rack;
• determining a first number of iterative dilations that are performed for the iteratively dilated first contour to extend into the zone adjacent to the rack;
• iteratively dilating, from the approximate head height toward the floor of the space, a second contour associated with the second person at least until the iteratively dilated second contour extends into the zone adjacent to the rack;
• determining a second number of iterative dilations that are performed for the iteratively dilated second contour to extend into the zone adjacent to the rack;
• in response to determining that the first number of iterative dilations is less than the second number of iterative dilations, determine that the action associated with the detected event was performed by the first person;
• and
• in response to determining that the second number of iterative dilations is less than the first number of iterative dilations, determine that the action associated with the detected event was performed by the second person;
• in response to determining the action associated with the detected event was performed by the first person, assigning the action to the first person;
• and
• in response to determining the action associated with the detected event was performed by the second person, assigning the action to the second person.

A tracking subsystem coupled to an image sensor, wherein the image sensor is positioned above a rack in a space and configured to generate top-view images of at least a portion of the space comprising the rack, the tracking subsystem configured to:

• receive an image feed comprising frames of the top-view images generated by the sensor;
• detect an event, wherein the detected event is associated with a portion of a person entering a zone adjacent to the rack;
• in response to detecting the event, determine that a first person or a second person may be associated with the detected event;
• in response to determining that the first or the second person may be associated with the detected event, store buffer frames of top-view images generated by the sensor during a time period associated with the detected event;
• determine, using at least one of the stored buffer frames and a first action-detection algorithm, whether an action associated with the detected event was performed by the first person or the second person, wherein the first action-detection algorithm is configured to determine whether the action associated with the detected event was performed by the first person or the second person by:
• iteratively dilating, from an approximate head height of one or both of the first person and second person toward a floor of the space, a first contour associated with the first person at least until the iteratively dilated first contour extends into the zone adjacent to the rack;
• determining a first number of iterative dilations that are performed for the iteratively dilated first contour to extend into the zone adjacent to the rack;
• iteratively dilating, from the approximate head height toward the floor of the space, a second contour associated with the second person at least until the iteratively dilated second contour extends into the zone adjacent to the rack;
• determining a second number of iterative dilations that are performed for the iteratively dilated second contour to extend into the zone adjacent to the rack;
• in response to determining that the first number of iterative dilations is less than the second number of iterative dilations, determine that the action associated with the detected event was performed by the first person;
• and
• in response to determining that the second number of iterative dilations is less than the first number of iterative dilations, determine that the action associated with the detected event was performed by the second person;
• in response to determining that the action associated with the detected event was performed by the first person, assign the action to the first person;
• and
• in response to determining that the action associated with the detected event was performed by the second person, assign the action to the second person.