Methods and devices for estimating weight of an object to be inspected in an inspection system

Patent metadata

Field	Value
Publication number	US-10379252-B2
Application number	US-201615217787-A
Country	US
Kind code	B2
Filing date	Jul 22, 2016
Priority date	Jul 22, 2015
Publication date	Aug 13, 2019
Grant date	Aug 13, 2019

Abstract

Disclosed is a method and device for estimating weight of an object to be inspected in an inspection system. An effective atomic number and a high-energy gray value of the dual-energy corresponding to each pixel of the object to be inspected are obtained by a dual-energy radiation scanning. A mass-thickness value for a corresponding pixel is obtained from a pre-created mass-thickness attenuation curve by utilizing the effective atomic numbers and the high-energy gray value of the dual-energy for respective pixels. Weight information for at least a part of the object to be inspected is calculated by multiplying the mass-thickness value by the area of the pixel. Such a method may accurately calculate the weight of the object to be inspected and save the cost for a conventional weighing hardware.

First claim

We claim:

1. A method for estimating a weight of an object to be inspected in an inspection system, comprising:
obtaining an effective atomic number and a dual-energy high-energy grayscale feature value corresponding to each pixel of the object to be inspected by a dual-energy radiation scanning;
obtaining a mass-thickness value for a corresponding pixel from a pre-created mass-thickness attenuation curve by utilizing the effective atomic number and the dual-energy high-energy grayscale feature value for respective pixels; and
calculating weight information for at least a part of the object to be inspected by multiplying the mass-thickness value by an area of the pixel.

2. The method according to claim 1 , further comprising:
estimating a physical dimension corresponding to each pixel on an image of the object to be inspected in a direction in which detectors are arranged, based on a pitch between detector pixels, a distance between an X-ray source and the detectors, and a distance between the X-ray source and the object to be inspected;
obtaining a pixel physical dimension in a scanning direction based on a scanning speed and an acquiring frequency of the detectors; and
obtaining an area of each pixel by multiplying the physical dimension in the direction in which the detectors are arranged by the pixel physical dimension in the scanning direction.

3. The method according to claim 1 , further comprising creating the pre-created mass-thickness attenuation curve by:
utilizing different types of calibration material blocks with known thicknesses to acquire a relationship curve among an X-ray attenuation coefficient, the effective atomic number, and the mass-thickness value, as the pre-created mass-thickness attenuation curve.

4. The method according to claim 1 , wherein the obtaining a mass-thickness value for a corresponding pixel comprises acquiring the mass-thickness value corresponding to both of the effective atomic number and dual-energy high-energy grayscale feature value is acquired by linear interpolation.

5. The method according to claim 1 , wherein the calculating weight information for at least a part of the object to be inspected comprises acquiring the weight information for a region of interest by accumulating weights of pixels within the region of interest when information of the region of interest selected by a user is received.

6. A device for estimating a weight of an object to be inspected in an inspection system, the device comprising:
one or more processors; and
a memory connected to the one or more processors and having one or more programs stored therein, which, when executed by the one or more processors, cause the one or more processors to be configured to:
obtain an effective atomic number and a dual-energy high-energy grayscale feature value corresponding to each pixel of the object to be inspected by a dual-energy radiation scanning;
obtain a mass-thickness value for a corresponding pixel from a pre-created mass-thickness attenuation curve by utilizing the effective atomic number and the dual-energy high-energy grayscale feature value for respective pixels; and
calculate weight information for at least a part of the object to be inspected by multiplying the mass-thickness value by an area of the pixel.

7. A method for estimating a weight of an object to be inspected in an inspection system, the method comprising:
obtaining a grayscale feature value corresponding to each pixel of an object to be inspected by a single-energy radiation scanning;
obtaining a mass-thickness value for a corresponding pixel from a pre-created mass-thickness attenuation curve by utilizing the grayscale feature value corresponding to respective pixels; and
calculating weight information for at least a part of the object to be inspected by multiplying the mass-thickness value by an area of the pixel.

8. The method according to claim 7 , further comprising:
estimating a physical dimension corresponding to each pixel on an image of the object to be inspected in a direction in which detectors are arranged, based on a pitch between detector pixels, a distance between a X-ray source and the detectors, and a distance between the X-ray source and the object to be inspected;
obtaining a pixel physical dimension in a scanning direction based on a scanning speed and an acquiring frequency of the detectors; and
obtaining an area of each pixel by multiplying the physical dimension in the direction in which the detectors are arranged by the pixel physical dimension in the scanning direction.

9. The method according to claim 7 , further comprising creating the pre-created mass-thickness attenuation curve by:
utilizing a calibration material block with a known thickness to acquire a relationship curve among an X-ray attenuation coefficient and the mass-thickness value, as the pre-created mass-thickness attenuation curve.

10. The method according to claim 7 , further comprising selecting aluminum as a calibration material block to acquire the pre-created mass-thickness attenuation curve.

11. The method according to claim 7 , wherein the calculating weight information for at least a part of the object to be inspected comprises acquiring the weight information for a region of interest by accumulating weights of pixels within the region of interest when information of the region of interest selected by a user is received.

12. A device for estimating a weight of an object to be inspected in an inspection system, the device comprising:
one or more processors; and
a memory connected to the one or more processors and having one or more programs stored therein, which, when executed by the one or more processors, cause the one or more processors to be configured to:
obtain a grayscale feature value corresponding to each pixel of an object to be inspected by a single-energy radiation scanning;
obtain a mass-thickness value for a corresponding pixel from a pre-created mass-thickness attenuation curve by utilizing the grayscale feature value corresponding to respective pixels; and
calculate weight information for at least a part of the object to be inspected by multiplying the mass-thickness value by an area of the pixel.

Assignees

• Univ Tsinghua
• Nuctech Co Ltd

Inventors

• Chen Zhiqiang
• Li Yuanjing
• Zhang Li
• Zhao Ziran
• Liu Yaohong
• Zheng Juan
• Gu Jianping
• Zong Chunguang

Classifications

• G01V5/0016

  Physics · mapped topic

• G01N23/04

  and forming images of the material · CPC title

• G01N23/083

  the radiation being X-rays · CPC title

• G01V5/005

  Physics · mapped topic

• G01V5/0041 Primary

  Physics · mapped topic