Identifying and evaluating possible horizontal and vertical lines intersecting potential pallet features

• US 8,718,372 B2
• Filed: 10/16/2012
• Issued: 05/06/2014
• Est. Priority Date: 10/19/2011
• Status: Active Grant

• Current Assignee: Crown Equipment Corporation
• Original Assignee: Crown Equipment Corporation
• Inventors: Holeva, Lee F., Elston, Edwin R., Seelinger, Michael J.
• Primary Examiner(s): Park, Edward
• Application Number:
  US13/652,524
• Publication Number:
  US 20130101227A1
• Time in Patent Office: 567 Days
• Field of Search: 382/181, 382/202, 382/231, 382/100
• US Class Current: 382/181
• CPC Class Codes: B66F 9/122 longitudinally movable
• CPC Class Codes: B66F 9/24 Electrical devices or systems
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 7/13 Edge detection
• CPC Class Codes: G06T 7/20 Analysis of motion motion estimation for coding, decoding, compressing or decompressing digital video signals H04N19/43, H04N19/51

Abstract

A method is provided for tracing a line from a possible corner of a pallet. The method may comprise: providing a Ro image; identifying, using a computer, a possible pallet corner in the Ro image; positioning, using the computer, a J×K window over at least respective portions of a plurality of rows in the Ro image including at least a portion of a row containing the possible corner; calculating, using the computer, an average of pixel values for each row in the J×K window; determining, using the computer, one of the rows in the J×K window having an average pixel value nearest a current pixel location being considered for inclusion in a line being traced and defining the one row as a nearest row; and deciding, using the computer, whether the nearest row is over a pallet.

Claims

1. A method for tracing a line from a possible corner of a pallet comprising:

providing a Ro image comprising pixels that may generally correspond to an orthogonal distance from an origin point to one or more possible lines in a corresponding grey scale image;

identifying, using a computer, a possible pallet corner in the Ro image;

positioning, using the computer, a J×

K window over at least respective portions of a plurality of rows in the Ro image including at least a portion of a row containing said possible corner;

calculating, using the computer, an average of pixel values for each row in said J×

K window;

determining, using the computer, one of said rows in said J×

K window having an average pixel value nearest a current pixel location being considered for inclusion in a line being traced and defining said one row as a nearest row; and

deciding, using the computer, whether said nearest row is over a pallet, wherein said current pixel location is included in said line being traced when said nearest row is over a pallet.

2. The method of claim 1, wherein said positioning comprises centering said J×

K window over said row portion in the Ro image containing said possible corner with said possible corner located along an edge of said window.

3. The method of claim 1, wherein said deciding comprises solving the following equation:

4. The method of claim 3, wherein if it is decided that said nearest row in said J×

K window is not over a pallet, further comprising;

centering, using the computer, an L×

M window over said nearest row, wherein said L×

M window is larger than said J×

K window;

calculating, using a computer, an average of pixel values for each row in said L×

M window;

determining, using the computer, one of said rows in said L×

M window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced and defining said one row as a nearest row; and

deciding, using the computer, whether said nearest row in said L×

M window is over a pallet.

5. The method of claim 4, wherein if it is decided that said nearest row in said L×

M window is not over a pallet, further comprising;

repeatedly;

centering a subsequent L×

M window over a previously determined L×

M window nearest row,

determining, using the computer, one of said rows in said subsequent L×

M window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced, and

deciding, using the computer, whether said nearest row in said subsequent L×

M window is over a pallet;

until it has been decided that a nearest row in a subsequent L×

M window is over the pallet or a predefined sequential number of subsequently determined nearest rows are not positioned over a pallet.

6. The method of claim 3, wherein if it is decided that said nearest row in said J×

K window is over a pallet, further comprising;

stepping, with the computer, said J×

K window horizontally one pixel;

centering, with the computer, said stepped J×

K window over a new row collinear with said previously determined nearest row;

calculating, using the computer, an average of pixel values for each row in said stepped J×

K window;

determining, using the computer, one of said rows in said stepped J×

K window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced and defining said one row as a nearest row; and

deciding, using the computer, whether said nearest row in said stepped J×

K window is over a pallet.

7. The method of claim 6, wherein if it is decided that said nearest row in said stepped J×

K window is over a pallet, further comprising;

repeatedly stepping said J×

K window horizontally until it is decided that a nearest row in a subsequently stepped J×

K window is not over a pallet or a predefined number of pixels of said line being traced have been located.

8. The method of claim 6, wherein if it is decided that said one determined row in said stepped J×

K window is not over a pallet, further comprising;

positioning, using the computer, a L×

M window over said nearest row in said stepped J×

K window, wherein said L×

M window is larger than said J×

K window;

calculating, using the computer, an average of pixel values for each row in said L×

M window;

determining, using the computer, one of said rows in said L×

M window having an average pixel value nearest a current pixel location being considered for inclusion in a line being traced and defining said one row as a nearest row; and

deciding, using the computer, whether said nearest row in said L×

M window is over a pallet.

9. A system for tracing a line from a possible corner of a pallet comprising:

a computer configured to provide a Ro image comprising pixels that may generally correspond to an orthogonal distance from an origin point to one or more possible lines in a corresponding grey scale image;

said computer further configured to identify a possible pallet corner in the Ro image;

said computer further configured to position a J×

K window over at least portions of a plurality of rows in the Ro image including at least a portion of a row containing said possible corner;

said computer configured to calculate an average of pixel values for each row in said J×

K window;

said computer further configured to determine one of said rows in said J×

K window having an average pixel value nearest a current pixel location being considered for inclusion in a line being traced and defining said one row as a nearest row; and

said computer further configured to decide whether said nearest row is over a pallet, wherein said current pixel location is included in said line being traced when said nearest row is over the pallet.

10. The system of claim 9, wherein said computer is further configured to center said J×

K window over said row portion in the Ro image containing said possible corner with said possible corner located along an edge of said window.

11. The system of claim 10, wherein if said computer decides that said nearest row in said J×

K window is not over a pallet, said computer is further configured to;

center an L×

M window over said nearest row, wherein said L×

M window is larger than said J×

K window;

calculate an average of pixel values for each row in said L×

M window;

determine one of said rows in said L×

M window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced and defining said one row as a nearest row; and

decide whether said nearest row in said L×

M window is over a pallet.

12. The system of claim 10, wherein if said computer decides that said nearest row in said J×

K window is over a pallet, said computer is further configured to;

step said J×

K window horizontally one pixel;

center said stepped J×

K window over a new row collinear with said previously determined row;

calculate an average of pixel values for each row in said stepped J×

K window;

determine one of said rows in said stepped J×

K window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced and defining said one row as a nearest row; and

decide whether said nearest row in said stepped J×

K window is over a pallet.

13. The system of claim 9, wherein said computer is further configured to solve the following equation:

14. The system of claim 13, wherein if said computer decides that said nearest row in said L×

M window is not over a pallet, said computer is further configured to;

repeatedly center a subsequent L×

M window over a previously determined nearest L×

M window row until said computer has decided that a nearest row in a subsequent L×

M window is over the pallet or a predefined sequential number of subsequently determined nearest rows are not positioned over a pallet.

15. The system of claim 13, wherein if said computer decides that said nearest row in said stepped J×

K window is over a pallet, said computer is further configured to;

repeatedly step said J×

K window horizontally until it is decided that a nearest row in a subsequently stepped J×

K window is not over a pallet or a predefined number of pixels of said line being traced have been located.

16. The system of claim 13, wherein if said computer has decided that said nearest row in said stepped J×

K window is not over a pallet, said computer is further configured to;

position a L×

M window over said nearest row in said stepped J×

K window, wherein said L×

M window is larger than said J×

K window;

calculate an average of pixel values for each row in said L×

M window;

determine one of said rows in said L×

M window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced and defining said one row as a nearest row; and

decide whether said nearest row in said L×

M window is over a pallet.

17. A computer program product for tracing a line from a possible corner of a pallet, comprising:

a non-transitory computer readable storage medium having computer readable program code embodied therewith, the computer readable program code comprising;

computer readable program code configured to provide a Ro image comprising pixels that may generally correspond to an orthogonal distance from an origin point to one or more possible lines in a corresponding grey scale image;

computer readable program code configured to identify a possible pallet corner in the Ro image;

computer readable program code configured to position a J×

K window over at least portions of a plurality of rows in the Ro image including at least a portion of a row containing said possible comer;

computer readable program code configured to calculate an average of pixel values for each row in said J×

K window;

computer readable program code configured to determine one of said rows in said J×

K window having an average pixel value nearest a current pixel location being considered for inclusion in a line being traced and defining said one row as a nearest row; and

computer readable program code configured to decide whether said nearest row is over a pallet, wherein said current pixel location is included in said line being traced when said nearest row is over the pallet.

18. The computer program product of claim 17, further comprising:

computer readable program code configured to center said J×

K window over said row portion in the Ro image containing said possible corner with said possible corner located along an edge of said window.

19. The computer program product of claim 17, further comprising:

computer readable program code configured to solve the following equation;

20. The computer program product of claim 19, wherein when said computer readable program code decides that said nearest row in said J×

K window is not over a pallet, said computer program product further comprises;

computer readable program code configured to center an L×

M window over said nearest row, wherein said L×

M window is larger than said J×

K window;

computer readable program code configured to calculate an average of pixel values for each row in said L×

M window;

computer readable program code configured to determine one of said rows in said L×

M window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced and defining said one row as a nearest row; and

computer readable program code configured to decide whether said nearest row in said L×

M window is over a pallet.

21. The computer program product of claim 20, wherein when said computer readable program code decides that said nearest row in said L×

M window is not over a pallet, said computer program product further comprises;

computer readable program code configured to repeatedly center a subsequent L×

M window over a previously determined nearest L×

M window row until said computer readable program code has decided that a nearest row in a subsequent L×

M window is over the pallet or a predefined sequential number of subsequently determined nearest rows are not positioned over a pallet.

22. The computer program product of claim 19, wherein when said computer readable program code decides that said nearest row in said J×

K window is over a pallet, said computer program product further comprises;

computer readable program code configured to step said J×

K window horizontally one pixel;

computer readable program code configured to center said stepped J×

K window over a new row collinear with said previously determined row;

computer readable program code configured to calculate an average of pixel values for each row in said stepped J×

K window;

computer readable program code configured to determine one of said rows in said stepped J×

K window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced and defining said one row as a nearest row; and

computer readable program code configured to decide whether said nearest row in said stepped J×

K window is over a pallet.

23. The computer program product of claim 22, wherein when said computer readable program code decides that said nearest row in said stepped J×

K window is over a pallet, said computer program product further comprises;

repeatedly step said J×

K window horizontally until it is decided that a nearest row in a subsequently stepped J×

K window is not over a pallet or a predefined number of pixels of said line being traced have been located.

24. The computer program product of claim 22, wherein when said computer readable program code has decided that said nearest row in said stepped J×

K window is not over a pallet, said computer program product further comprises;

computer readable program code configured to position a L×

M window over said nearest row in said stepped J×

K window, wherein said L×

M window is larger than said J×

K window;

computer readable program code configured to calculate an average of pixel values for each row in said L×

M window;

computer readable program code configured to determine one of said rows in said L×

M window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced and defining said one row as a nearest row; and

computer readable program code configured to decide whether said nearest row in said L×

M window is over a pallet.

25. A method for tracing a line from a possible corner of a pallet comprising:

providing a Ro image comprising pixels that may generally correspond to an orthogonal distance from an origin point to one or more possible lines in a corresponding grey scale image;

identifying, using a computer, a possible pallet corner in the Ro image;

positioning, using the computer, a P×

Q window over at least portions of a plurality of columns of the Ro image including at least a portion of a column containing said possible corner;

calculating, using the computer, an average of pixel values for each column in said P×

Q window;

determining, using the computer, one of said columns in said P×

Q window having an average pixel value nearest a current pixel location being considered for inclusion in a line being traced and defining said one column as a nearest column; and

deciding, using the computer, whether said nearest column is over a pallet, wherein said current pixel location is included in said line being traced when said nearest column is over the pallet.

26. The method of claim 25, wherein said positioning comprising centering said P×

Q window over said column portion in the Ro image containing said possible corner with said possible corner located along an edge of said window.

27. The method of claim 25, wherein said deciding comprises solving the following equation:

28. The method of claim 27, wherein if it is decided that said nearest column is not over a pallet, further comprising:

centering, using the computer, an R×

S window over said nearest column, wherein said R×

S window is larger than said P×

Q window;

calculating, using the computer, an average of pixel values for each column in said R×

S window;

determining, using the computer, one of said columns in said R×

S window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced and defining said one column as a nearest column; and

deciding, using the computer, whether said nearest column in said R×

S window is over a pallet.

29. The method of claim 28, wherein if it is decided that said nearest column in said R×

S window is not over a pallet, further comprising;

repeatedly centering a subsequent R×

S window over a previously determined R×

S window nearest column until it has been decided that a nearest column in a subsequent R×

S window is over the pallet or a predefined sequential number of subsequently determined nearest columns are not positioned over a pallet.

30. The method of claim 27, wherein if it is decided that said nearest column is over a pallet, further comprising:

stepping, with the computer, said P×

Q window vertically one pixel;

centering, with the computer, said P×

Q window over a new column in said P×

Q window collinear with said previously determined nearest column;

calculating, using the computer, an average of pixel values for each column in said stepped P×

Q window;

determining, using the computer, one of said columns in said stepped P×

Q window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced and defining said one column as a nearest column; and

deciding, using the computer, whether said nearest column in said stepped P×

Q window is over a pallet.

31. The method of claim 30, wherein if it is decided that said nearest column in said stepped P×

Q window is over a pallet, further comprising;

repeatedly stepping said P×

Q window vertically until it is decided that a nearest column in a subsequently stepped P×

Q window is not over a pallet or a predefined number of pixels of the line being traced have been located.

32. The method of claim 30, wherein if it is decided that said nearest column in said stepped P×

Q window is not over a pallet, further comprising;

positioning, using the computer, a R×

S window over said nearest column in said stepped P×

Q window, wherein said R×

S window is larger than said P×

Q window;

calculating, using the computer, an average of pixel values for each column portion in said R×

S window;

determining, using the computer, one of said columns in said R×

S window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced and defining said one column as a nearest column; and

deciding, using the computer, whether said nearest column is over a pallet.

33. A system for tracing a line from a possible corner of a pallet comprising:

a computer configured to provide a Ro image comprising pixels that may generally correspond to an orthogonal distance from an origin point to one or more possible lines in a corresponding grey scale image;

said computer further configured to identify a possible pallet corner in the Ro image;

said computer further configured to position a P×

Q window over at least portions of a plurality of columns of the Ro image including at least a portion of a column containing said possible corner;

said computer further configured to calculate an average of pixel values for each column in said P×

Q window;

said computer further configured to determine one of said columns in said P×

Q window having an average pixel value nearest a current pixel location of said line being traced and defining said one column as a nearest column; and

said computer further configured to decide whether said nearest column is over a pallet, wherein said current pixel location is included in said line being traced when said nearest column is over the pallet.

34. The system of claim 33, wherein said computer is further configured to center said P×

Q window over said column portion in the Ro image containing said possible corner with said possible corner located along an edge of said window.

35. The system of claim 34, wherein if said computer decides that said nearest column in said R×

S window is not over a pallet, said computer is further configured to;

repeatedly center a subsequent R×

S window over a previously determined R×

S window nearest column until it has been decided that a nearest column in a subsequent R×

S window is over the pallet or a predefined sequential number of subsequently determined nearest columns are not positioned over a pallet.

36. The system of claim 33, wherein said computer is further configured to solve the following equation:

37. The system of claim 36, wherein if said computer decides that said nearest column is not over a pallet, said computer is further configured to:

center an R×

S window over said nearest column, wherein said R×

S window is larger than said P×

Q window;

calculate an average of pixel values for each column in said R×

S window;

determine one of said columns in said R×

S window having an average pixel value nearest a current pixel location being considered for inclusion in a line being traced and defining said one column as a nearest column; and

decide whether said nearest column in said R×

S window is over a pallet.

38. The system of claim 36, wherein if said computer decides that said nearest column is over a pallet, said computer is further configured to:

step said P×

Q window vertically one pixel;

center said P×

Q window over a new column in said P×

Q window collinear with said previously determined column;

calculate an average of pixel values for each column in said stepped P×

Q window;

determine one of said columns in said stepped P×

Q window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced and defining said one column as a nearest column; and

decide whether said nearest column in said stepped P×

Q window is over a pallet.

39. The system of claim 38, wherein if said computer decides that said nearest column in said stepped P×

Q window is over a pallet, said computer is further configured to;

repeatedly step said P×

Q window vertically until it is decided that a determined nearest column in a subsequently stepped P×

Q window is not over a pallet or a predefined number of pixels of said line being traced have been located.

40. The system of claim 38, wherein if said computer decides that said nearest column in said stepped P×

Q window is not over a pallet, said computer is further configured to;

position a R×

S window over said one determined column in said stepped P×

Q window, wherein said R×

S window is larger than said P×

Q window;

calculate an average of pixel values for each column portion in said R×

S window;

determine one of said columns in said R×

S window having an average pixel value nearest a current pixel location being considered for inclusion in a line being traced and defining said one column as a nearest column; and

decide whether said nearest column is over a pallet.

41. A computer program product for tracing a line from a possible corner of a pallet, comprising:

a non-transitory computer readable storage medium having computer readable program code embodied therewith, the computer readable program code comprising;

computer readable program code configured to provide a Ro image comprising pixels that may generally correspond to an orthogonal distance from an origin point to one or more possible lines in a corresponding grey scale image;

computer readable program code configured to identify a possible pallet corner in the Ro image;

computer readable program code configured to position a P×

Q window over at least portions of a plurality of columns of the Ro image including at least a portion of a column containing said possible corner;

computer readable program code configured to calculate an average of pixel values for each column in said P×

Q window;

computer readable program code configured to determine one of said columns in said P×

Q window having an average pixel value nearest a current pixel location of said line being traced and defining said one column as a nearest column; and

computer readable program code configured to decide whether said nearest column is over a pallet, wherein said current pixel location is included in said line being traced when said nearest column is over the pallet.

42. The computer program product of claim 41, further comprising:

computer readable program code configured to center said P×

Q window over said column portion in the Ro image containing said possible corner with said possible corner located along an edge of said window.

43. The computer program product of claim 41, further comprising:

computer readable program code configured to solve the following equation;

44. The computer program product of claim 43, wherein when said computer readable program code decides that said nearest column is not over a pallet, said computer program product further comprises:

computer readable program code configured to center an R×

S window over said nearest column, wherein said R×

S window is larger than said P×

Q window;

computer readable program code configured to calculate an average of pixel values for each column in said R×

S window;

computer readable program code configured to determine one of said columns in said R×

S window having an average pixel value nearest a current pixel location being considered for inclusion in a line being traced and defining said one column and a nearest column; and

computer readable program code configured to decide whether said nearest column in said R×

S window is over a pallet.

45. The computer program product of claim 44, wherein when said computer readable program code decides that said nearest column in said R×

S window is not over a pallet, said computer program product further comprises;

computer readable program code configured to repeatedly center a subsequent R×

S window over a previously determined R×

S window nearest column until it has been decided that a nearest column in a subsequent R×

S window is over the pallet or a predefined sequential number of subsequently determined nearest columns are not positioned over a pallet.

46. The computer program product of claim 43, wherein when said computer readable program code decides that said nearest column is over a pallet, said computer program product further comprises:

computer readable program code configured to step said P×

Q window vertically one pixel;

computer readable program code configured to center said P×

Q window over a new column in said P×

Q window collinear with said previously determined column;

computer readable program code configured to calculate an average of pixel values for each column in said stepped P×

Q window;

computer readable program code configured to determine one of said columns in said stepped P×

Q window having an average pixel value nearest a current pixel location being considered for inclusion in said line being traced and defining said one column as a nearest column; and

computer readable program code configured to decide whether said nearest column in said stepped P×

Q window is over a pallet.

47. The computer program product of claim 46, wherein when said computer readable program code decides that said nearest column in said stepped P×

Q window is over a pallet, said computer program product further comprises;

computer readable program code configured to repeatedly step said P×

Q window vertically until it is decided that a determined nearest column in a subsequently stepped P×

Q window is not over a pallet or a predefined number of pixels of said line being traced have been located.

48. The computer program product of claim 46, wherein when said computer readable program code decides that said nearest column in said stepped P×

Q window is not over a pallet, said computer program product further comprises;

computer readable program code configured to position a R×

S window over said one determined column in said stepped P×

Q window, wherein said R×

S window is larger than said P×

Q window;

computer readable program code configured to calculate an average of pixel values for each column portion in said R×

S window;

computer readable program code configured to determine one of said columns in said R×

S window having an average pixel value nearest a current pixel location being considered for inclusion in a line being traced and defining said one column as a nearest column; and

computer readable program code configured to decide whether said nearest column is over a pallet.