DEVICE, METHOD AND PROGRAM FOR MEASURING NUMBER OF PASSENGERS

• US 20150278617A1
• Filed: 10/10/2013
• Published: 10/01/2015
• Est. Priority Date: 10/26/2012
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Oami, Ryoma
• Granted Patent: US 9,760,784 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06T 1/60 Memory management
• CPC Class Codes: G06V 20/593 Recognising seat occupancy
• CPC Class Codes: G06V 40/161 Detection; Localisation; Normalisation

Abstract

Although persons on board in a driver'"'"'s seat and a passenger seat can be detected, it is difficult to detect persons on board in a back seat and thus the number of passengers cannot be accurately measured. Image obtaining means 100 photographs the inside of a vehicle from the outside of the vehicle (a shoulder, etc.). View determining means 102 estimates the way in which the vehicle in the image photographed by the image obtaining means 100 is viewed, and outputs a view determination result. Person detecting means 101 performs front-face, side-face, and angled-face detection on the image photographed by the image obtaining means 100, to detect persons and outputs a person detection result. In-vehicle position estimating means 103 determines at which positions in the vehicle the detected persons are present, using the person detection information and the view determination result information, and outputs in-vehicle position estimation information. Result integrating means 104 integrates detection results obtained for a plurality of images which are photographed consecutively, to calculate the number of passengers.

Claims

1. A device for measuring a number of passengers, comprising:

an image obtaining unit for obtaining an image;

a person detecting unit for detecting persons on board a vehicle from the obtained image and generating a person detection result, the vehicle being a target for measuring a number of persons;

a view determining unit for determining view indicating how the vehicle is viewed in the image, and generating a view determination result;

an in-vehicle position estimating unit for estimating, from the person detection result and the view determination result, at which positions in the vehicle the persons are on board and generating, for each image, an in-vehicle position estimation result; and

a result integrating unit for integrating the plurality of in-vehicle position estimation results obtained for the vehicle and determining a number of passengers from an integration result.

2. The device for measuring a number of passengers according to claim 1, further comprising:

a vehicle movement information obtaining unit for obtaining information about a movement state of the vehicle and generating the information as vehicle movement information; and

a trigger unit for generating a trigger signal based on the vehicle movement information and according to predetermined timing, wherein

the image obtaining unit obtains an image in accordance with the trigger signal.

3. The device for measuring a number of passengers according to claim 2, wherein

the vehicle movement information obtaining unit determines, for each of one or more predetermined points, whether the vehicle has passed through the predetermined point, and generates vehicle movement information based on a result of measurement of a time of the passage, and

the predetermined timing is determined based on the time of the passage through the predetermined point included in the vehicle movement information.

4. The device for measuring a number of passengers according to claim 2, wherein

the vehicle movement information obtaining unit measures a speed of the vehicle, and the vehicle movement information includes a result of the measurement of the speed of the vehicle, and

the predetermined timing is adjusted based on the speed of the vehicle included in the vehicle movement information.

5. The device for measuring a number of passengers according to claim 1, wherein the image obtaining unit includes an infrared illuminator, and obtains an image by projecting light into the vehicle in accordance with image obtaining timing and photographing light in an infrared wavelength range.

6. The device for measuring a number of passengers according to claim 1, wherein the person detection result is generated by performing a process of detecting a face on the obtained image.

7. The device for measuring a number of passengers according to claim 1, wherein the view determining unit determines view by detecting a window pane of the vehicle from the image obtained by the image obtaining unit.

8. The device for measuring a number of passengers according to claim 1, wherein the in-vehicle position estimating unit compares positions at which the persons sitting at seat positions in the vehicle are seen in the image and which are assumed based on the view determination result, with positions of the persons in the image included in the person detection result, to determine in which seats in the image the detected persons have sat.

9. A method for measuring a number of passengers, comprising:

obtaining an image;

detecting persons on board a vehicle from the obtained image and generating a person detection result, the vehicle being a target for measuring a number of persons;

determining view indicating how the vehicle is viewed in the image, and generating a view determination result;

estimating, from the person detection result and the view determination result, at which positions in the vehicle the persons are on board and generating, for each image, an in-vehicle position estimation result; and

integrating the plurality of in-vehicle position estimation results obtained for the vehicle and determining a number of passengers from an integration result.

10. A non-transitory computer-readable recording medium in which a program for measuring a number of passengers is recorded, the program causing a computer to perform:

a process of obtaining an image;

a process of detecting persons on board a vehicle from the obtained image and generating a person detection result, the vehicle being a target for measuring a number of persons;

a process of determining view indicating how the vehicle is viewed in the image, and generating a view determination result;

a process of estimating, from the person detection result and the view determination result, at which positions in the vehicle the persons are on board and generating, for each image, an in-vehicle position estimation result; and

a process of integrating the plurality of in-vehicle position estimation results obtained for the vehicle and determining a number of passengers from an integration result.