VEHICLE INSPECTION METHODS AND SYSTEMS

• US 20170017667A1
• Filed: 09/30/2016
• Published: 01/19/2017
• Est. Priority Date: 12/30/2014
• Status: Active Grant

• Current Assignee: Nuctech Company Limited (Tsinghua Tongfang Co., Ltd.), Tsinghua University
• Original Assignee: Nuctech Company Limited (Tsinghua Tongfang Co., Ltd.), Tsinghua University
• Inventors: Chen, Zhiqiang, ZHANG, Li, ZHAO, Ziran, LIU, Yaohong, GU, Jianping, HU, Zheng, LI, Qiang
• Granted Patent: US 10,289,699 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01N 2223/401 image processing
• CPC Class Codes: G01N 2223/631 large structures, walls
• CPC Class Codes: G01N 23/04 and forming images of the material
• CPC Class Codes: G01V 5/0016 Active interrogation, i.e. using an external radiation source, e.g. using pulsed, continuous or cosmic rays
• CPC Class Codes: G01V 5/22 Active interrogation, i.e. by irradiating objects or goods using external radiation sources, e.g. using gamma rays or cosmic rays
• CPC Class Codes: G06F 16/54 Browsing; Visualisation therefor
• CPC Class Codes: G06F 16/5838 using colour
• CPC Class Codes: G06F 18/22 Matching criteria, e.g. proximity measures
• CPC Class Codes: G06T 2207/10116 X-ray image
• CPC Class Codes: G06T 2207/30268 Vehicle interior
• CPC Class Codes: G06T 7/001 using an image reference approach
• CPC Class Codes: G06T 7/337 involving reference images or patches
• CPC Class Codes: G06V 2201/05 Recognition of patterns representing particular kinds of hidden objects, e.g. weapons, explosives, drugs
• CPC Class Codes: G06V 2201/08 Detecting or categorising vehicles

Abstract

A vehicle inspection method and system are disclosed. In one aspect, the method includes acquiring a transmission image of an inspected vehicle. The method further includes acquiring a transmission image template of a vehicle model corresponding to the model of the inspected vehicle from a database. The method further includes performing registration on the transmission image of the inspected vehicle and the transmission image template. The method further includes determining a difference between a transmission image after the registration and a transmission image template after the registration, to obtain a difference area of the transmission image of the vehicle relative to the transmission image template. The method further includes processing the difference area to determine whether the vehicle carries a suspicious object or not. In some embodiments, this solution can avoid the problems of a detection loophole and a poor effect of manually determining an image in a conventional manner, and is important to assist the security inspection for small vehicles.

Claims

1. A vehicle inspection method comprising:

acquiring a transmission image of an inspected vehicle;

acquiring a transmission image template of a vehicle model corresponding to the model of the inspected vehicle from a database;

performing registration on the transmission image of the inspected vehicle and the transmission image template;

determining a difference between a transmission image after the registration and a transmission image template after the registration, to obtain a difference area of the transmission image of the vehicle relative to the transmission image template; and

processing the difference area to determine whether the vehicle carries a suspicious object.

2. The vehicle inspection method according of claim 1, wherein said acquiring a transmission image template of the vehicle model corresponding to the model of the inspected vehicle from a database comprises:

retrieving the transmission image template of the vehicle model from the database based on a unique identifier of the inspected vehicle.

3. The vehicle inspection method according of claim 1, wherein said acquiring a transmission image template of a vehicle model corresponding to the model of the inspected vehicle from a database comprises:

extracting information on an internal structure of the vehicle from the transmission image, and retrieving the transmission image template of the vehicle model from the database based on the information on the internal structure and information on external features of the vehicle.

4. The vehicle inspection method according of claim 1, wherein said performing registration on the transmission image of the inspected vehicle and the transmission image template comprises:

performing rigid registration on the transmission image of the inspected vehicle and the transmission image template to have global transformation and alignment on the image; and

performing elastic registration on the transmission image of the inspected vehicle and the transmission image template to eliminate local deformation.

5. The vehicle inspection method according of claim 4, wherein said performing rigid registration comprises:

performing feature extraction on two images to obtain feature points;

finding a pair of matched feature points through similarity measurement;

obtaining image spatial coordinate transformation parameters based on the pair of matched feature points; and

performing image registration on the image spatial coordinate transformation parameters.

6. The vehicle inspection method according of claim 1, further comprising:

performing normalization on gray levels of two images after rigid registration, before elastic registration.

7. The vehicle inspection method according of claim 1, further comprising:

removing parts of the transmission image that are outside the image of the vehicle.

8. The vehicle inspection method according of claim 1, further comprising:

marking the suspicious object in the difference area.

9. A vehicle inspection system, comprising:

a radiation image system configured to acquire a transmission image of an inspected vehicle;

an image processing unit configured to acquire a transmission image template of a vehicle model corresponding to the model of the inspected vehicle from a database, perform registration on the transmission image of the inspected vehicle and the transmission image template, determine a difference between a transmission image after the registration and a transmission image template after the registration to obtain a difference area of the transmission image of the vehicle relative to the transmission image template, and process the difference area to determine whether the vehicle carries a suspicious object.

10. The vehicle inspection system according of claim 9, wherein, the image processing unit is further configured to:

extract information on an internal structure of the vehicle from the transmission image; and

retrieve the transmission image template of the vehicle model from the database based on the information on the internal structure and information on external features of the vehicle.