Apparatus and method for generating a two-dimensional representation of an object portion arbitrarily arranged within an object

• US 8,155,429 B2
• Filed: 04/24/2007
• Issued: 04/10/2012
• Est. Priority Date: 04/25/2006
• Status: Active Grant

• Current Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Original Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Inventors: Scholz, Oliver, Kostka, Guenther, Wenzel, Thomas
• Primary Examiner(s): Arana, Louis
• Application Number:
  US12/298,318
• Publication Number:
  US 20090202133A1
• Time in Patent Office: 1,813 Days
• Field of Search: 382/149, 382/141, 382/152, 382/107, 382/128
• US Class Current: 382/149
• CPC Class Codes: G06T 2207/10116 X-ray image
• CPC Class Codes: G06T 2207/30164 Workpiece; Machine component
• CPC Class Codes: G06T 5/50 using two or more images, e.g. averaging or subtraction
• CPC Class Codes: G06T 5/70 Denoising; Smoothing
• CPC Class Codes: G06T 7/0004 Industrial image inspection

Abstract

For generating a two-dimensional representation of an object portion arbitrarily arranged within an object, a first image comprising the object, and subsequently a second image comprising the object are generated by means of an imaging device while the object and the imaging device are moving relative to each other. By means of a signal processor, information about a position and a shape of the object portion of interest within the object and its relative motion is received so as to combine, on the basis of the information received, image portions, within the first and second images, which are associated with the object portion of interest.

Claims

1. An apparatus comprising:

an imager adapted to generate a first image comprising a two-dimensional projection of an object, and to subsequently generate a second image comprising a further two-dimensional projection of the object, while the object and the imager are moving relative to each other;

a signal processor adapted to generate a two-dimensional representation of an object portion arbitrarily arranged within the object, and to receive information about a position and a shape of the object portion within the object and its relative motion so as to combine, on the basis of the information received, dots within image portions within the first image and within the second image which are associated with the object portion; and

a determiner adapted to determine the relative motion of the object on the basis of information from the first and second images, the determiner being configured to determine the relative motion of the object on the basis of distinctive details of the object or a sample incorporated in the object.

2. The apparatus as claimed in claim 1, adapted to generate a plurality of two-dimensional representations of object portions arbitrarily arranged within the object, the signal processor being adapted to detect, for each of the object portions represented, information about shapes and positions of the object portions within the object.

3. The apparatus as claimed in claim 1, wherein the signal processor is adapted to generate a two-dimensional projection of the object portion from the first and second images.

4. The apparatus as claimed in claim 1, wherein the signal processor is adapted to superimpose the image portions from the first and second images.

5. The apparatus as claimed in claim 1, wherein the information about the position and the shape of the object portion to be represented comprises volume dots within the object, the signal processor being adapted to calculate, on the basis of the relative motion of the object, a position of the volume dot, associated with the object portion, within the first and second images.

6. The apparatus as claimed in claim 1, wherein the determiner is configured to determine the relative motion of the object rotating about an axis.

7. The apparatus as claimed in claim 6, wherein the object is a device under test displaced from a rotational plane or from a picture-taking geometry because of casting burrs.

8. The apparatus as claimed in claim 6, wherein the determiner adapted to determine the relative motion of the object is further configured to take into account, from a position of a distinctive detail within the first image, an estimation of a position of the distinctive detail within the second image.

9. The apparatus as claimed in claim 8, wherein the determiner is further configured to model the relative motion of the object.

10. The apparatus as claimed in claim 7, wherein the distinctive details comprise corners, edges, bright or dark patches, openings or bores of the object.

11. The apparatus as claimed in claim 1, wherein the relative motion is a linear motion.

12. The apparatus as claimed in claim 1, wherein the relative motion is a rotational motion.

13. The apparatus as claimed in claim 12, wherein the object portion comprises any shape and position within the object, except for a subarea which is arranged in a radially symmetric manner in relation to an axis of rotation of the rotational motion.

14. The apparatus as claimed in claim 1, configured to project a three-dimensional object onto a two-dimensional detector.

15. The apparatus as claimed in claim 1, configured to calculate positions of projected pixels of a surface area within the object in accordance with positions of a subset of volume dots of the object.

16. The apparatus as claimed in claim 1, configured to calculate a surface area within the object using image details within at least one of the first and second images.

17. The apparatus as claimed in claim 1, configured to average over related projections of a volume dot of the object.

18. The apparatus as claimed in claim 1, configured to calculate several surface areas of various shapes and positions from a plurality of generated images.

19. A method comprising:

sensing a first image comprising a two-dimensional projection of an object,

sensing a second image comprising a further two-dimensional projection of the object,

receiving information about a position and a shape of an object portion arbitrarily arranged within the object;

determining a relative motion of the object on the basis of information from the first and second images about distinctive details of the object or a sample incorporated in the object; and

on the basis of the information received, generating a two-dimensional representation of the object portion arbitrarily arranged within the object by combining dots of image portions, within the first and second images, which are associated with the object portion.

20. The method as claimed in claim 19 comprising:

receiving information about the shape and the position within the object for each of a plurality of the object portions.

21. The method as claimed in claim 19, comprising:

two-dimensionally projecting the object portion from the first and second images.

22. The method as claimed in claim 19, comprising:

superimposing the image portions from the first and second images.

23. The method as claimed in claim 19, comprising:

sensing volume-dot information about the position and the shape of the object; and

calculating a position of volume dots on the basis of the relative motion of the object within the first and second images.

24. The method as claimed in claim 19, comprising:

determining the relative motion of the object rotating about an axis.

25. The method as claimed in claim 24, wherein the object is a device under test displaced from a rotational plane or from a picture-taking geometry because of casting burrs.

26. The method as claimed in claim 25, wherein the step of determining further comprises estimating a position of a distinctive detail within the second image on the basis of a position of the distinctive detail within the first image.

27. The method as claimed in claim 26, wherein the step of determining further comprises modeling the relative motion of the object.

28. The method as claimed in claim 26, wherein the distinctive details comprise corners, edges, bright or dark patches, openings or bores of the object.

29. The method as claimed in claim 19, wherein the object undergoes linear motion.

30. The method as claimed in claim 19, wherein the object undergoes rotational motion.

31. The method as claimed in claim 30, wherein the object portion comprises any shape and position, except for a subarea which is arranged in a radially symmetric manner in relation to an axis of rotation of the rotation motion.

32. A non-transitory computer readable medium storing a computer program comprising a program code for performing, when the computer program is executed on a computer, a method comprising:

sensing a first image comprising a two-dimensional projection of an object,

sensing a second image comprising a further two-dimensional projection of the object,

receiving information about a position and a shape of an object portion arbitrarily arranged within the object;

determining a relative motion of the object on the basis of information from the first and second images about distinctive details of the object or a sample incorporated in the object; and

on the basis of the information received, generating a two-dimensional representation of the object portion arbitrarily arranged within the object by combining dots of image portions, within the first and second images, which are associated with the object portion.