Smart scan

• US 7,277,579 B2
• Filed: 05/31/2002
• Issued: 10/02/2007
• Est. Priority Date: 05/31/2002
• Status: Active Grant

• Current Assignee: Arosoft, Inc.
• Original Assignee: ArcSoft, Inc.
• Inventors: Huang, Hua
• Primary Examiner(s): Chen; Wenpeng
• Assistant Examiner(s): Ge; Yuzhen
• Application Number:
  US10/159,707
• Publication Number:
  US 20030231803A1
• Time in Patent Office: 1,950 Days
• Field of Search: 382/175
• US Class Current: 382/173
• 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 of said image against a document cover of a scanner, said document cover comprising a geometric feature;

(b) following said geometric feature of said document cover in said composite image, wherein said geometric feature comprises a line in said document cover;

(c) detecting at least two breakpoints in said geometric feature where said image superimposes said geometric feature;

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

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

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

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

4. The method of claim 1, wherein said document cover comprises a backdrop of a first color and said geometric feature of a second color.

5. The method of claim 4, wherein said plurality of geometric features comprises more than four 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 geometric feature comprises following a vertical line in both an upward direction and a downward direction.

8. The method of claim 1, wherein said detecting at least two breakpoints comprises detecting a change in color value of a pixel while following said geometric feature.

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

(a) receiving a composite image of said image against a document cover of a scanner, said document cover comprising vertical and horizontal lines;

(b) following said vertical lines of said document cover in said composite image;

(c) detecting a first plurality of breakpoints in said vertical lines where said image superimposes said vertical lines;

(d) following said horizontal lines of said document cover in said composite image;

(e) detecting a second plurality of breakpoints in said horizontal lines where said image superimposes said horizontal lines; and

(f) determining a border of said image from coordinates of said first and said second pluralities of breakpoints.

10. The method of claim 9, wherein said determining a border of said 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 image further comprises extending said linear edges until each intersects with two other linear edges to form said border.

12. The method of claim 9, wherein said document cover comprises a backdrop of a first color, said vertical lines of a second color, and said horizontal lines of said second color.

13. The method of claim 12, wherein said first color is blue and said second color is green.

14. The method of claim 12, wherein said following vertical lines comprises following each vertical line in both an upward direction and a downward direction, and said following horizontal lines comprises following each horizontal line in both a rightward direction and a leftward direction.

15. The method of claim 9, wherein said detecting a first plurality of breakpoints and said detecting a second plurality of breakpoints each comprises detecting a change in color value of a pixel while following a respective line.

16. The method of claim 9, wherein the document cover comprises more than four vertical lines and more than four horizontal lines.