Detection device, detection method, computer program product, and information processing system

A detection method implemented by a detection device comprising:

• acquiring an image including an area in which a mobile body is movable;
• detecting at least the area, a mark on the area, and a person, from the image;
• calculating a first distance between the person and a position of the device when the person is in the area;
• and
• setting a range around a position at which the person is detected, according to a result of the detection and the first distance, the range being an area range in which any person is estimated to be present after the person is detected;
• storing the area range in association with positional information at a first time period;
• and
• presenting the area range to a user at a second time period, wherein the second time period corresponds to a time period during which the detection device is within a particular distance of the area range corresponding to the positional information regardless of the presence of a person within the area range, and wherein the second time period occurs later than the first time period.

An information processing system comprising:

• a server device;
• and
• a detection device, wherein the detection device comprises:
• a camera configured to acquire a captured image captured including an area in which a mobile body is movable, and positional information representing a position at which the captured image is captured;
• processing circuitry configured to:
• detect at least the area, a mark on the area, and a person, from the captured image;
• calculate a distance between the person and a position of the detection device when the person is in the area;
• set a range around a position at which the person is detected, according to a result of detection performed by the processor circuitry and the distance, the range being an area range in which any person is estimated to be present after the person is detected;
• store the area range in association with positional information at a first time period;
• and
• present the area range to a user at a second time period, wherein the second time period corresponds to a time period during which the detection device is within a particular distance of the area range corresponding to the positional information regardless of the presence of a person within the area range, and wherein the second time period occurs later than the first time period;
• a first transmitter configured to transmit, to the server device, at least one first set of the positional information and the range;
• a first receiver configured to receive a second set of the positional information and the range transmitted from the server device;
• and
• a first storage configured to store therein the second set and the first set, and
• the server device comprises:
• a second receiver configured to receive the first set transmitted from the detection device;
• a second storage configured to store the first set received by the second receiver, as the second set;
• and
• a second transmitter configured to transmit the second set stored in the second storage, to the detection device.