Smart scan

• US 20030231803A1
• Filed: 05/31/2002
• Published: 12/18/2003
• Est. Priority Date: 05/31/2002
• Status: Active Grant

• Current Assignee: Arosoft, Inc.
• Original Assignee: Arosoft, Inc.
• Inventors: Huang, Hua
• Granted Patent: US 7,277,579 B2
• Time in Patent Office: Days
• US Class Current: 382/282
• CPC Class Codes: G06T 2207/10008 from scanner, fax or copier
• CPC Class Codes: G06T 2207/30176 Document
• CPC Class Codes: G06T 7/12 Edge-based segmentation
• CPC Class Codes: G06T 7/194 involving foreground-background segmentation
• CPC Class Codes: G06V 30/1478 of characters or characters lines
• CPC Class Codes: H04N 1/3872 Repositioning or masking

Abstract

A method for determining a border of an image includes (a) receiving a composite image including a background image and a foreground image, (b) following one geometric feature (e.g., a line) of the background image, and (c) detecting two or more breakpoints in the first geometric feature where the foreground image superimposes the geometric feature. Actions (b) and (c) are repeated to detect breakpoints for a number of the geometric features. The border of the foreground image is determined by constructing linear edges that each connects three or more breakpoints and extending the linear edges until each intersect with two other linear edges to form the border of the foreground image.

An apparatus for determining a border of an image includes a scanner and a document cover. The document cover includes a blue backdrop and geometric features. The geometric features include green vertical and horizontal lines.

Claims

1. A method for determining a border of an image, comprising:

(a) receiving a composite image including a background image and a foreground image;

(b) following a first geometric feature of said background image;

(c) detecting two or more breakpoints in said first geometric feature where said foreground image superimposes said first geometric feature;

(d) repeating actions (b) to (c) to detect a first plurality of breakpoints of a plurality of first geometric features; and

(e) determining a border of said foreground image from coordinates of said first plurality of breakpoints.

2. The method of claim 1, wherein said determining a border of said foreground image comprises constructing linear edges that each connects at least three of said first plurality of breakpoints.

3. The method of claim 2, wherein said determining a border of said foreground image further comprises extending said linear edges until each intersect with two other linear edges to form said border.

4. The method of claim 1, wherein said background image comprises a backdrop of a first color and first geometric features of a second color.

5. The method of claim 4, wherein said first geometric features comprises vertical lines.

6. The method of claim 4, wherein said first color is blue and said second color is green.

7. The method of claim 5, wherein said following a first geometric feature comprises following a vertical line in an upward direction and a downward direction.

8. The method of claim 1, wherein said detecting two or more breakpoint comprises detecting a change in color value of a pixel while following said first geometric feature.

9. The method of claim 1, further comprising:

(f) following a second geometric feature of said background image;

(g) detecting two or more breakpoints in said second geometric feature where said foreground image superimposes said second geometric feature;

(h) repeating actions (f) and (g) to detecting a second plurality of breakpoints of a plurality of second geometric features;

(i) wherein said determining a border of said foreground image further comprises determining said border from coordinates of said second plurality of breakpoints.

10. The method of claim 9, wherein said determining a border of said foreground image comprises constructing linear edges that each connects at least three breakpoints from said first and said second pluralities of breakpoints.

11. The method of claim 10, wherein said determining a border of said foreground image further comprises extending said linear edges until each intersect with two other linear edges to form said border.

12. The method of claim 9, wherein said background image comprises a backdrop of a first color, said first geometric features of a second color, and said second geometric features of said second color.

13. The method of claim 12, wherein said first geometric features comprises vertical lines and said second geometric features comprise horizontal lines.

14. The method of claim 13, wherein said first color is blue and said second color is green.

15. The method of claim 13, wherein said following a second geometric feature comprises following a horizontal line both in a rightward direction and in a leftward direction.

16. The method of claim 9, wherein said detecting two or more breakpoint comprises detecting a change in color value of a pixel while following said first geometric feature.

17. An apparatus for determining a border of an image, comprising:

a scanner; and

a document cover, said document cover comprising a pattern with a backdrop and a plurality of first geometric features.

18. The apparatus of claim 17, wherein said first geometric features are vertical lines.

19. The apparatus of claim 18, wherein said pattern further comprises a plurality of second geometric features.

20. The apparatus of claim 19, wherein said second geometric features are horizontal lines.

21. The apparatus of claim 20, wherein said backdrop is blue and said vertical and said horizontal lines are green.