Parcel imaging system and method

• US 20070237356A1
• Filed: 04/04/2007
• Published: 10/11/2007
• Est. Priority Date: 04/07/2006
• Status: Abandoned Application

• Current Assignee: SICK Incorporated (Sick)
• Original Assignee: SICK Incorporated (Sick)
• Inventors: Dwinell, John, Bian, Long
• Application Number:
  US11/732,546
• Publication Number:
  US 20070237356A1
• Time in Patent Office: Days
• US Class Current: 382/101
• CPC Class Codes: B07C 3/14 using light-responsive detecting means for information carriers G06K7/14
• CPC Class Codes: G06T 3/4038 Image mosaicing, e.g. composing plane images from plane sub-images
• CPC Class Codes: G06T 5/009 Global, i.e. based on properties of the image as a whole applied in cameras using an electronic image sensor H04N23/80, H04N23/70
• CPC Class Codes: G06T 5/40 using histogram techniques
• CPC Class Codes: G06T 5/92 based on global image properties
• CPC Class Codes: G06T 7/30 Determination of transform parameters for the alignment of images, i.e. image registration
• CPC Class Codes: G06V 10/12 Details of acquisition arrangements; Constructional details thereof
• CPC Class Codes: G06V 10/16 using multiple overlapping images; Image stitching

Abstract

A parcel imaging system includes means for transporting parcels and image sensors oriented to image the parcels. An image construction subsystem is configured to stitch together outputs of the image sensors to produce at least one two-dimensional images of a parcel, and to construct, using the at least one two-dimensional image, at least one displayable three-dimensional image of the parcel.

Claims

1. A parcel imaging system comprising:

means for transporting parcels;

image sensors oriented to image the parcels; and

an image construction subsystem configured to;

stitch together outputs of the image sensors to produce at least one two-dimensional image of a parcel, and

construct, using the at least one two-dimensional image, at least one displayable three-dimensional image of the parcel.

2. The system of claim 1 in which the image construction subsystem is configured to construct the at least one displayable three-dimensional image of the parcel using at least two two-dimensional images of the parcel.

3. The system of claim 1 further including a general dimension subsystem including parcel dimension information.

4. The system of claim 3 in which the image construction subsystem is configured to construct the at least one displayable three-dimensional image of the parcel using one two-dimensional image of the parcel and at least one parcel dimension.

5. The system of claim 1 in which the at least one three-dimensional image of the parcel does not include any background image.

6. The system of claim 3 further including a background stripper subsystem configured to strip any background image from the at least one two-dimensional image using a combination of image contrast information and parcel dimension information.

7. The system of claim 6 in which the background stripper subsystem is configured to:

determine pixel coordinates of a corner of the parcel in the least one two-dimensional image using the parcel dimension information;

conduct line scans proximate the corner;

calculate an average numerical value of the pixels in each line scan;

detect a significant change in the average numerical value of the pixels of the line scans proximate the pixel coordinates of the corner; and

set the pixel coordinates of the corner to pixel coordinate values where the significant change in the average numerical value of the pixels of the line scans was detected.

8. The system of claim 7 in which the background stripper subsystem is further configured to conduct multi-level detection and set the pixel coordinates of the corner using sub-sampling of the at least one two-dimensional image.

9. The system of claim 7 in which the background stripper subsystem is configured to set the pixel coordinates of four corners of the parcel in the at least one two-dimensional image.

10. The system of claim 7 in which the background stripper subsystem is configured to strip any background image outside of the set pixel coordinates and the dimensions of the two-dimensional image of the parcel.

11. The system of claim 6 in which the background stripper subsystem is configured to:

determine pixel coordinates of a point on the parcel in the least one two-dimensional image using the parcel dimension information;

conduct line scans proximate said point;

calculate an average numerical value of the pixels in each line scan;

detect a significant change in the average numerical value of the pixels of the line scans proximate the pixel coordinates of said point; and

set the pixel coordinates of said point to pixel coordinate values where the significant change in the average numerical value of the pixels of the line scans was detected.

12. The system of claim 11 in which the parcel dimension information is general parcel dimension information.

13. The system of claim 12 in which the background stripper subsystem is configured to locate a plurality of points on the two-dimensional image of the parcel.

14. The system of claim 13 in which the background stripper subsystem is further configured to create a mapping of said points in the two-dimensional image, and using said mapping, formulate at least one line representing at least one edge of the parcel in the two-dimensional image.

15. The system of claim 14 in which the background stripper subsystem is further configured to formulate lines representing each edge of the parcel in the two-dimensional image.

16. The system of claim 10 in which the image construction subsystem is configured to construct the at least one displayable three-dimensional image from stripped two-dimensional images.

17. The system of claim 11 in which the image construction subsystem is configured to construct the at least one displayable three-dimensional image by fitting the stripped two-dimensional images into a three-dimensional frame.

18. The system of claim 1 in which the two-dimensional images are less than full resolution.

19. The system of claim 18 in which the image construction subsystem is configured to sample each two dimensional image.

20. The system of claim 19 in which the image construction subsystem is configured to compress each two-dimensional image.

21. The system of claim 1 in which the image construction subsystem is configured to display any view of the at least one displayable three-dimensional image of the parcel.

22. The system of claim 1 further including a rotation module configured to rotate the at least one displayable three-dimensional image of the parcel.

23. The system of claim 3 further including a brightness adjustment module configured to adjust the brightness of the at least one three-dimensional image of the parcel.

24. The system of claim 23 in which the brightness adjustment module is configured to:

normalize the brightness of each visible face of the at least one three-dimensional image of the parcel; and

adjust the normalized brightness depending on the orientation of the parcel.

25. The system of claim 24 in which the brightness adjustment module is configured to normalize the brightness of each visible face of the at least one three-dimensional image of the parcel by:

generating a histogram of a visible face of the at least one three-dimensional image of the parcel;

determining from the histogram the maximum of the histogram of the visible face;

determining the maximum of a gray level of the visible face using the histogram;

calculating the size of the visible face using parcel dimension information;

setting maximum brightness of the visible face at a predetermined value;

generating an interrelationship between the maximum of the histogram, the maximum of the gray level, and the size of the visible face;

plotting a correlation curve based on the interrelationship; and

interpolating a normalized output image using the correlation curve.

26. The system of claim 25 in which the brightness adjustment module is configured to adjust the normalized brightness by:

detecting a normal vector for a visible face of the at least one three-dimensional image of the parcel;

determining a z-vector value for the normal vector detected; and

multiplying the z-vector value by the normalized brightness of the visible face.

27. The system of claim 1 further including a dimensioning module configured to display parcel dimensions with the at least one three-dimensional image of the parcel.

28. The system of claim 1 in which the image construction subsystem is configured to store the three-dimensional image of the parcel in a file.

29. The system of claim 23 in which said file further includes data concerning said parcel.

30. The system of claim 29 in which said data includes bar code data.

31. The system of claim 30 in which said data includes parcel dimension data.

32. The system of claim 1 in which the image sensors are line scan cameras.

33. A parcel imaging method comprising:

transporting parcels;

imaging the parcels with image sensors;

stitching together outputs of the image sensors to produce at least one two-dimensional image of a parcel; and

constructing, using the at least one two-dimensional image, at least one displayable three-dimensional image of the parcel.

34. The method of claim 33 in which constructing the at least one displayable three-dimensional image of the parcel includes using at least two two-dimensional images of the parcel.

35. The method of claim 33 further including a general dimension subsystem including parcel dimension information.

36. The method of claim 35 in which constructing the at least one displayable three-dimensional image of the parcel includes using one two-dimensional image of the parcel and at least one parcel dimension.

37. The method of claim 33 in which the at least one three-dimensional image of the parcel does not include any background image.

38. The method of claim 37 in which the background image is stripped from the two-dimensional image using a combination of image contrast information and parcel dimension information.

39. The method of claim 38 in which the background image is stripped from the two-dimensional image by the steps comprising:

determining pixel coordinates of a corner of the parcel in the least one two-dimensional image using the parcel dimension information;

conducting line scans proximate the corner;

calculating an average numerical value of the pixels in each line scan;

detecting a significant change in the average numerical value of the pixels of the line scans proximate the pixel coordinates of the corner; and

setting the pixel coordinates of the corner to pixel coordinate values where the significant change in the average numerical value of the pixels of the line scans was detected.

40. The method of claim 39 including conducting multi-level detection and setting the pixel coordinates of the corner using sub-sampling of the at least one two-dimensional image.

41. The method of claim 39 including setting the pixel coordinates of four corners of the parcel in the at least one two-dimensional image.

42. The method of claim 39 including stripping any background image outside of the set pixel coordinates and the dimensions of the two-dimensional image of the parcel.

43. The method of claim 38 in which the background image is stripped from the two-dimensional image by the steps comprising:

determining pixel coordinates of a point on the parcel in the least one two-dimensional image using the parcel dimension information;

conducting line scans proximate said point;

calculating an average numerical value of the pixels in each line scan;

detecting a significant change in the average numerical value of the pixels of the line scans proximate the pixel coordinates of said point; and

setting the pixel coordinates of said point to pixel coordinate values where the significant change in the average numerical value of the pixels of the line scans was detected.

44. The method of claim 43 in which the parcel dimension information is general parcel dimension information.

45. The method of claim 44 including locating a plurality of points on the two-dimensional image of the parcel.

46. The method of claim 45 further including creating a mapping of said points and from said mapping formulating at least one line representing at least one edge of the parcel in the two-dimensional image.

47. The method of claim 46 further including formulating lines representing each edge of the parcel in the two-dimensional image.

48. The method of claim 42 including constructing the at least one displayable three-dimensional image from stripped two-dimensional images.

49. The method of claim 48 including constructing the at least one displayable three-dimensional image by fitting the stripped two-dimensional images into a three-dimensional frame.

50. The method of claim 33 in which the two-dimensional images are less than full resolution.

51. The method of claim 50 in which each two-dimensional image is sampled.

52. The method of claim 50 further including compressing each two-dimensional image.

53. The method of claim 33 further including displaying any view of the at least one three-dimensional image of the parcel.

54. The method of claim 33 further including rotating the at least one displayable three-dimensional image of the parcel.

55. The method of claim 33 further including adjusting the brightness of the at least three-dimensional image of the parcel.

56. The method of claim 55 in which adjusting the brightness includes the steps comprising:

normalizing the brightness of each visible face of the at least one three-dimensional image of the parcel; and

adjusting the normalized brightness depending on the orientation of the parcel.

57. The method of claim 56 in which normalizing the brightness includes the steps comprising:

generating a histogram of a visible face of the at least one three-dimensional image of the parcel;

determining from the histogram the maximum of the histogram of the visible face;

determining the maximum of a gray level of the visible face using the histogram;

calculating the size of the visible face using parcel dimension information;

setting maximum brightness of the visible face at a predetermined value;

generating an interrelationship between the maximum of the histogram, the maximum of the gray level, and the size of the visible face;

plotting a correlation curve based on the interrelationship; and

interpolating a normalized output image using the correlation curve.

58. The method of claim 57 in which adjusting the normalized brightness includes the steps comprising:

detecting a normal vector for a visible face of the at least one three-dimensional image of the parcel;

determining a z-vector value for the normal vector detected; and

multiplying the z-vector value by the normalized brightness of the visible face.

59. The method of claim 33 further including displaying parcel dimensions with the at least one three-dimensional image of the parcel.

60. The method of claim 33 further including storing the at least one three-dimensional image of the parcel in a file.

61. The method of claim 60 in which said file further includes data concerning said parcel.

62. The method of claim 61 in which said data includes bar code data.

63. The method of claim 61 in which said data includes parcel dimension data.

64. The method of claim 33 in which the image sensors are line scan cameras.

65. A parcel shipping method comprising:

moving parcels through a tunnel at a primary shipping installation to determine the dimensions of the parcels and to decode bar code information present on the parcels;

imaging each parcel to store at least one displayable three-dimensional image of the parcel; and

associating bar code information and/or dimensions of the parcel with the three-dimensional image to identify the parcel, establish the condition of the parcel at the shipping installation, establish the dimensions of the parcel, and/or to detect and/or prevent fraud.

66. The method of claim 65 in which imaging each parcel to store at least one displayable three-dimensional image of the parcel includes imaging shipping labels on the parcel.

67. The method of claim 66 further including imaging each parcel at a second shipping installation to store at least one displayable three-dimensional image of the parcel at the second shipping installation.

68. The method of claim 67 in which imaging each parcel at a second installation includes imaging shipping labels on the parcel.

69. The method of claim 68 further including generating an alert signal if the parcel fails to arrive at a destination in accordance with a shipping label imaged at the primary shipping installation.

70. The method of claim 69 further including conducting a search for the parcel.

71. The method of claim 69 further including generating an alarm signal if the destination in accordance with the shipping label imaged at the second shipping installation is not the destination in accordance with a shipping label imaged at the primary shipping installation.

72. The method of claim 65 in which the tunnel includes line scan cameras oriented to image the parcel.

73. The method of claim 72 in which imaging each parcel includes:

stitching together outputs of the line scan cameras to produce at least one two-dimensional image of a parcel, and

constructing, using the at least one two-dimensional images, at least one displayable three-dimensional image of the parcel.