Technique for locating objects within an image

• US 6,434,271 B1
• Filed: 02/06/1998
• Issued: 08/13/2002
• Est. Priority Date: 02/06/1998
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Compaq Computer Corporation (HP Inc.)
• Inventors: Avery, Brian Lyndall, Christian, Andrew Dean
• Primary Examiner(s): Couso, Jose L.
• Assistant Examiner(s): DESIRE, GREGORY M
• Application Number:
  US09/020,043
• Time in Patent Office: 1,649 Days
• Field of Search: 382/174, 382/187, 382/190-199, 382/103, 382/168, 382/203, 382/266, 382/286, 382/291, 348/169, 348/415.1, 707/20
• US Class Current: 382/194
• CPC Class Codes: G06V 40/103 Static body considered as a whole, e.g. static pedestrian or occupant recognition

Abstract

A technique for locating objects within an image is disclosed. In one embodiment, the technique is realized by obtaining an image and then identifying an object within the image based upon an orientation of the object within the image. The image can be a representation of a plurality of pixels, wherein the plurality of pixels are arranged in a plurality of columns and rows, and wherein at least some of the plurality of pixels are enabled to represent the object.

Claims

1. A method for locating objects within an image, wherein an object is represented by a plurality of enabled pixels within the image, the method comprising the steps of:

defining a first representation of the image, the first representation having a plurality of first pixels,

obtaining a second and a third representation of the image;

the second representation having a plurality of second pixels, and the third representation having a plurality of third pixels,

forming the plurality of first pixels by taking the difference between the plurality of second pixels and the plurality of third pixels, wherein at least some of the plurality of first pixels are enabled and represent the object,

defining at least two orientations of the object;

counting the number of enabled plurality of first pixels along the each of the two orientations;

defining a threshold as a quantity of the plurality of first pixels counted;

identifying portions of the plurality of first pixels exceeding the threshold; and

identifying the object within the image based upon the orientation and the identified portions of the plurality of first pixels exceeding the threshold of the object within the image.

2. The method as defined in claim 1, wherein the step of identifying an object within the image based upon an orientation of the object within the image includes the steps or:

grouping together substantially adjacent identified portions of the representation; and

identifying areas of the representation corresponding to each group of substantially adjacent identified portions of the representation.

3. The method as defined in claim 2, wherein the step of identifying an object within the image based upon an orientation of the object within the image further includes the steps of:

recording the locations of the outermost enabled pixels within each group of substantially adjacent identified portions of the representation; and

framing areas of the representation coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified portions of the representation.

4. The method as defined in claim 3, wherein the plurality of pixels are also configured having a third orientation, wherein the step of identifying an object within the image based upon an orientation of the object within the image further includes the steps of:

counting each enabled pixel in each framed area along the third orientation; and

identifying portions of each framed area having a quantity of enabled pixels exceeding a threshold value.

5. The method as defined in claim 4, wherein the step of identifying an object within the image based upon an orientation of the object within the image further includes the steps of:

grouping together substantially adjacent identified portions of each framed area; and

identifying areas of each framed area corresponding to each group of substantially adjacent identified portions of each framed area.

6. The method as defined in claim 5, wherein the step of identifying an object within the image based upon an orientation of the object within the image further includes the steps of:

recording the locations of the outermost enabled pixels within each group of substantially adjacent identified portions of each framed area; and

framing areas of each framed area coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified portions of each framed area.

7. The method as defined in claim 4, wherein the second orientation and the first orientation are orthogonal.

8. The method as defined in claim 1, wherein the image is a representation of a plurality of pixels, wherein the plurality of pixels are arranged in a plurality of columns, wherein at least some of the plurality of pixels are enabled to represent the object, wherein the step of identifying an object within the image based upon an orientation of the object within the image includes the steps of:

counting each enabled pixel in each of the plurality of columns; and

identifying each of the plurality of columns having a quantity of enabled pixels exceeding a threshold value.

9. The method as defined in claim 8, wherein the step of identifying an object within the image based upon an orientation of the object within the image further includes the steps of:

grouping together substantially adjacent identified columns; and

identifying areas of the representation corresponding to each group of substantially adjacent identified columns.

10. The method as defined in claim 9, wherein the step of identifying an object within the image based upon an orientation of the object within the image further includes the steps of:

recording the locations of the outermost enabled pixels within each group of substantially adjacent identified columns; and

framing areas of the representation coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified columns.

11. The method as defined in claim 1, wherein the image is a representation of a plurality of pixels, wherein the plurality of pixels are arranged in a plurality of rows, wherein at least some of the plurality of pixels are enabled to represent the object, wherein the step of identifying an object within the image based upon an orientation of the object within the image includes the steps of:

counting each enabled pixel in each of the plurality of rows; and

identifying each of the plurality of rows having a quantity of enabled first pixels exceeding a threshold value.

12. The method as defined in claim 11, wherein the step of identifying an object within the image based upon an orientation of the object within the image further includes the steps of:

grouping together substantially adjacent identified rows; and

identifying areas of the representation corresponding to each group of substantially adjacent identified rows.

13. The method as defined in claim 12, wherein the step of identifying an object within the image based upon an orientation of the object within the image further includes the steps of:

recording the locations of the outermost enabled pixels within each group of substantially adjacent identified rows; and

framing areas of the representation coinciding with the locations of the outermost enabled first pixels within each group of substantially adjacent identified rows.

14. The method as defined in claim 1, wherein the image is a representation of a plurality of pixels, wherein the plurality of pixels are arranged in a plurality of columns and rows, wherein at least some of the plurality of pixels are enabled to represent the object, wherein the step of identifying an object within the image based upon an orientation of the object within the image includes the steps of:

counting each enabled pixel in each of the plurality of columns and rows;

identifying each of the plurality of columns having a quantity of enabled pixels exceeding a column threshold value; and

identifying each of the plurality of rows having a quantity of enabled pixels exceeding a row threshold value.

15. The method as defined in claim 14, wherein the step of identifying an object within the image based upon an orientation of the object within the image further includes the steps of:

grouping together substantially adjacent identified columns;

grouping together substantially adjacent identified rows;

identifying areas of the representation corresponding to each group of substantially adjacent identified columns; and

identifying areas of the representation corresponding to each group of substantially adjacent identified rows.

16. The method as defined in claim 15, wherein the step of identifying an object within the image based upon an orientation of the object within the image further includes the steps of:

recording the locations of the outermost enabled pixels within each group of substantially adjacent identified columns;

recording the locations of the outermost enabled pixels within each group of substantially adjacent identified rows;

framing areas of the representation coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified columns; and

framing areas of the representation coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified rows.

17. The method as defined in claim 16, wherein the step of identifying an object within the image based upon an orientation of the object within the image further includes the steps of:

overlaying the areas of the representation that were framed to coincide with the locations of the outermost enabled pixels within each group of substantially adjacent identified columns with the areas of the representation that were framed to coincide with the locations of the outermost enabled pixels within each group of substantially adjacent identified rows; and

identifying common overlayed areas as areas of the representation that contain a significant number of enabled pixels.

18. The method as defined in claim 1, wherein the image is a first representation of a plurality of first pixels representing a difference between a second representation of a plurality of second pixels and a third representation of a plurality of third pixels, wherein each of the plurality of first pixels is enabled to represent a difference between a corresponding one of the plurality of second pixels and a corresponding one of the plurality of third pixels, wherein the object is represented by at least some of the enabled first pixels.

19. An apparatus for locating objects within an image, wherein the object is represented by a plurality of enabled pixels within the image, the apparatus comprising:

a first representation of the image, the first representation having a plurality of first pixels,

an obtainer for obtaining a second and a third representation of the image;

the second representation having a plurality of second pixels, and the third representation having a plurality of third pixels,

the plurality of first pixels formed by taking the difference between the plurality of second pixels and the plurality of third pixels, wherein at least some of the plurality of first pixels are enabled and represent the object,

means for defining at least two orientations of the object;

a counter of the number of enabled plurality of first pixels along the each of the two orientations;

means for defining a threshold as a quantity of the plurality of first pixels counted;

a first identifier of portions of the plurality of first pixels exceeding the threshold; and

a second identifier for identifying the object within the image based upon the orientation and the identified portions of the plurality of first pixels exceeding the threshold of the object within the image.

20. The apparatus as defined in claim 19, wherein the first identifier further includes:

a first grouper for grouping together substantially adjacent identified portions of the representation; and

a third identifier for identifying areas of the representation corresponding to each group of substantially adjacent identified portions of the representation.

21. The apparatus as defined in claim 20, wherein the first identifier further includes:

a first recorder for recording the locations of the outermost enabled pixels within each group of substantially adjacent identified portions of the representation; and

a first framer for framing areas of the representation coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified portions of the representation.

22. The apparatus as defined in claim 21, wherein the plurality of pixels are also configured having a third orientation, wherein the first identifier further includes:

a second counter for counting each enabled pixel in each framed area along the third orientation; and

a fourth identifier for identifying portions of each framed area having a quantity of enabled pixels exceeding a threshold value.

23. The apparatus as defined in claim 22, wherein the first identifier further includes:

a second grouper for grouping together substantially adjacent identified portions of each framed area; and

a fifth identifier for identifying areas of each framed area corresponding to each group of substantially adjacent identified portions of each framed area.

24. The apparatus as defined in claim 23, wherein the first identifier further includes;

a second recorder for recording the locations of the outermost enabled pixels within each group of substantially adjacent identified portions of each framed area; and

a second framer for framing areas of each framed area coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified portions of each framed area.

25. The apparatus as defined in claim 22, wherein the second orientation and the first orientation are orthogonal.

26. The apparatus as defined in claim 19, wherein the image is a representation of a plurality of pixels, wherein the plurality of pixels are arranged in a plurality of columns, wherein at least some of the plurality of pixels are enabled to represent the object, wherein the first identifier includes:

a counter for counting each enabled pixel in each of the plurality of columns; and

a second identifier for identifying each of the plurality of columns having a quantity of enabled pixels exceeding a threshold value.

27. The apparatus as defined in claim 26, wherein the first identifier further includes:

a grouper for grouping together substantially adjacent identified columns; and

a third identifier for identifying areas of the representation corresponding to each group of substantially adjacent identified columns.

28. The apparatus as defined in claim 27, wherein the first identifier further includes:

a recorder for recording the locations of the outermost enabled pixels within each group of substantially adjacent identified columns; and

a framer for framing areas of the representation coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified columns.

29. The apparatus as defined in claim 19, wherein the image is a representation of a plurality of pixels, wherein the plurality of pixels are arranged in a plurality of rows, wherein at least some of the plurality of pixels are enabled to represent the object, wherein the first identifier includes:

a counter for counting each enabled pixel in each of the plurality of rows; and

a second identifier for identifying each of the plurality of rows having a quantity of enabled first pixels exceeding a threshold value.

30. The apparatus as defined in claim 29, wherein the first identifier further includes:

a grouper for grouping together substantially adjacent identified rows; and

a third identifier for identifying areas of the representation corresponding to each group of substantially adjacent identified rows.

31. The apparatus as defined in claim 30, wherein the first, identifier further includes:

a recorder for recording the locations of the outermost enabled pixels within each group of substantially adjacent identified rows; and

a framer for framing areas of the representation coinciding with the locations of the outermost enabled first pixels within each group of substantially adjacent identified rows.

32. The apparatus as defined in claim 19, wherein the image is a representation of a plurality of pixels, wherein the plurality of pixels are arranged in a plurality of columns and rows, wherein at least some of the plurality of pixels are enabled to represent the object, wherein the first identifier includes:

a counter for counting each enabled pixel in each of the plurality of columns and rows;

a second identifier for identifying each of the plurality of columns having a quantity of enabled pixels exceeding a column threshold value; and

a third identifier for identifying each of the plurality of rows having a quantity of enabled pixels exceeding a row threshold value.

33. The apparatus as defined in claim 32, wherein the first identifier further includes:

a first grouper for grouping together substantially adjacent identified columns;

a second grouper for grouping together substantially adjacent identified rows;

a fourth identifier for identifying areas of the representation corresponding to each group of substantially adjacent identified columns; and

a fifth identifier for identifying areas of the representation corresponding to each group of substantially adjacent identified rows.

34. The apparatus as defined in claim 33, wherein the first identifier further includes:

a first recorder for recording the locations of the outermost enabled pixels within each group of substantially adjacent identified columns;

a second recorder for recording the locations of the outermost enabled pixels within each group of substantially adjacent identified rows;

a first framer for framing areas of the representation coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified columns; and

a second framer for framing areas of the representation coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified rows.

35. The apparatus as defined in claim 34, wherein the first identifier further includes:

an overlayer for overlaying the areas of the representation that were framed to coincide with the locations of the outermost enabled pixels within each group of substantially adjacent identified columns with the areas of the representation that were framed to coincide with the locations of the outermost enabled pixels within each group of substantially adjacent identified rows; and

a sixth identifier for identifying common overlayed areas as areas of the representation that contain a significant number of enabled pixels.

36. The apparatus as defined in claim 19, wherein the image is a first representation of a plurality of first pixels representing a difference between a second representation of a plurality of second pixels and a third representation of a plurality of third pixels, wherein each of the plurality of first pixels is enabled to represent a difference between a corresponding one of the plurality of second pixels and a corresponding one of the plurality of third pixels, wherein the object is represented by at least some of the enabled first pixels.

37. An article of manufacture for locating objects within an image, wherein the object is represented by a plurality of enabled pixels within the image, the article of manufacture comprising:

a computer readable storage medium; and

computer programming stored on the storage medium;

wherein the stored computer programming is configured to be readable from the computer readable storage medium by a computer and thereby cause the computer to operate so as to;

define a first representation of the image, the first representation having a plurality of first pixels,

obtain a second and a third representation of the image;

the second representation having a plurality of second pixels, and the third representation having a plurality of third pixels,

the plurality of first pixels formed by taking the difference between the plurality of second pixels and the plurality of third pixels, wherein at least some of the plurality of first pixels are enabled and represent the object,

define at least two orientations of the object;

count the number of enabled plurality of first pixels along the each of the two orientations;

define a threshold as a quantity of the plurality of first pixels counted;

identify of portions of the plurality of of first pixels exceeding the threshold; and

identify the object within the image based upon the orientation and the identified portions of the plurality of first pixels exceeding the threshold of the object within the image.

38. The article of manufacture as defined in claim 37, further causing the computer to operate so as to:

group together substantially adjacent identified portions of the representation; and

identify areas of the representation corresponding to each group of substantially adjacent identified portions of the representation.

39. The article of manufacture as defined in claim 38, further causing the computer to operate so as to:

record the locations of the outermost enabled pixels within each group of substantially adjacent identified portions of the representation; and

frame areas of the representation coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified portions of the representation.

40. The article of manufacture as defined in claim 39, wherein the plurality of pixels are also configured having a third orientation, further causing the computer to operate so as to:

count each enabled pixel in each framed area along the third orientation; and

identify portions of each framed area having a quantity of enabled pixels exceeding a threshold value.

41. The article of manufacture as defined in claim 40, further causing the computer to operate so as to:

group together substantially adjacent identified portions of each framed area; and

identify areas of each framed area corresponding to each group of substantially adjacent identified portions of each framed area.

42. The article of manufacture as defined in claim 41, further causing the computer to operate so as to:

record the locations of the outermost enabled pixels within each group of substantially adjacent identified portions of each framed area; and

frame areas of each framed area coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified portions of each framed area.

43. The article of manufacture as defined in claim 40, wherein the second orientation and the first orientation are orthogonal.

44. The article of manufacture as defined in claim 37, wherein the image is a representation of a plurality of pixels, wherein the plurality of pixels are arranged in a plurality of columns, wherein at least some of the plurality of pixels are enabled to represent the object, further causing the computer to operate so as to:

count each enabled pixel in each of the plurality of columns; and

identify each of the plurality of columns having a quantity of enabled pixels exceeding a threshold value.

45. The article of manufacture as defined in claim 44, further causing the computer to operate so as to:

group together substantially adjacent identified columns; and

identify areas of the representation corresponding to each group of substantially adjacent identified columns.

46. The article of manufacture as defined in claim 45, further causing the computer to operate so as to:

record the locations of the outermost enabled pixels within each group of substantially adjacent identified columns; and

frame areas of the representation coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified columns.

47. The article of manufacture as defined in claim 37, wherein the image is a representation of a plurality of pixels, wherein the plurality of pixels are arranged in a plurality of rows, wherein at least some of the plurality of pixels are enabled to represent the object, further causing the computer to operate so as to:

count each enabled pixel in each of the plurality of rows; and

identify each of the plurality of rows having a quantity of enabled first pixels exceeding a threshold value.

48. The article of manufacture as defined in claim 47, further causing the computer to operate so as to:

group together substantially adjacent identified rows; and

identify areas of the representation corresponding to each group of substantially adjacent identified rows.

49. The article of manufacture as defined in claim 48, further causing the computer to operate so as to:

record the locations of the outermost enabled pixels within each group of substantially adjacent identified rows; and

frame areas of the representation coinciding with the locations of the outermost enabled first pixels within each group of substantially adjacent identified rows.

50. The article of manufacture as defined in claim 37, wherein the image is a representation of a plurality of pixels, wherein the plurality of pixels are arranged in a plurality of columns and rows, wherein at least some of the plurality of pixels are enabled to represent the object, further causing the computer to operate so as to:

count each enabled pixel in each of the plurality of columns and rows;

identify each of the plurality of columns having a quantity of enabled pixels exceeding a column threshold value; and

identify each of the plurality of rows having a quantity of enabled pixels exceeding a row threshold value.

51. The article of manufacture as defined in claim 50, further causing the computer to operate so as to:

group together substantially adjacent identified columns;

group together substantially adjacent identified rows;

identify areas of the representation corresponding to each group of substantially adjacent identified columns; and

identify areas of the representation corresponding to each group of substantially adjacent identified rows.

52. The article of manufacture as defined in claim 51, further causing the computer to operate so as to:

record the locations of the outermost enabled pixels within each group of substantially adjacent identified columns;

record the locations of the outermost enabled pixels within each group of substantially adjacent identified rows;

frame areas of the representation coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified columns; and

frame areas of the representation coinciding with the locations of the outermost enabled pixels within each group of substantially adjacent identified rows.

53. The article of manufacture as defined in claim 52, further causing the computer to operate so as to:

overlay the areas of the representation that were framed to coincide with the locations of the outermost enabled pixels within each group of substantially adjacent identified columns with the areas of the representation that were framed to coincide with the locations of the outermost enabled pixels within each group of substantially adjacent identified rows; and

identify common overlayed areas as areas of the representation that contain a significant number of enabled pixels.

54. The article of manufacture as defined in claim 37, wherein the image is a first representation of a plurality of first pixels representing a difference between a second representation of a plurality of second pixels and a third representation of a plurality of third pixels, wherein each of the plurality of first pixels is enabled to represent a difference between a corresponding one of the plurality of second pixels and a corresponding one of the plurality of third pixels, wherein the object is represented by at least some of the enabled first pixels.