Scanning and detecting a number of images

• US 7,149,349 B2
• Filed: 09/24/2002
• Issued: 12/12/2006
• Est. Priority Date: 09/24/2001
• Status: Expired due to Fees

• Current Assignee: Canon Information Systems Research Australia Pty Limited (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Druitt, Colin Eric, Gallagher, Matthew William
• Primary Examiner(s): Wu, Jingge
• Assistant Examiner(s): Bayat, Ali
• Application Number:
  US10/252,522
• Publication Number:
  US 20030059111A1
• Time in Patent Office: 1,540 Days
• Field of Search: 382/162, 382/165, 382/167, 382/170, 382/173, 382/199, 382/190, 358518-523, 358/488, 358/474
• US Class Current: 382/165
• CPC Class Codes: H04N 1/38 Circuits or arrangements for blanking or otherwise eliminating unwanted parts of pictures H04N1/387 takes precedence
• CPC Class Codes: H04N 1/3872 Repositioning or masking

Abstract

The disclosed a number of methods for scanning and individually detecting a number of images on a scanner platen. In one method, the scanner scans the platen one scanline after another and performs the following steps for each scanline. The method first detects and groups together one or more consecutive pixels of a current scanline having substantially similar colors (804,808,806). The method then determines (826) those said groups of pixels of a current scanline which likely belong to images and those which likely belong to background of the scanner. The method then copies (708) the determined groups of pixels belonging to images of a current scanline to their respective images.

Claims

1. A method of scanning and individually copying a number of images on a scanner, the method performing the following steps:

detecting and grouping together one or more consecutive pixels of a current scanline;

updating a current background color of the scanner, wherein the current background color is derived from a previous background color and a color representative of the grouped pixels of the current scanline most likely to be part of a background;

determining said groups of pixels of a current scanline that are likely to belong to said images and those that are likely to belong to the background based upon said updated current background color; and

copying said determined groups of pixels belonging to images of a current scanline to their respective images.

2. A method as claimed in claim 1, wherein the representation of the current scanline represents edges of a pixel image of the current scanline.

3. A method as claimed in claim 1, wherein the representation of the current scanline represents a pixel image of the current scanline.

4. A method according to claim 1 wherein the pixels are grouped together based on a representation of said current scanline.

11. An image file produced by any one of the methods as claimed in claims 1, 5 or 10.

5. A method of scanning and individually copying a number of images on a scanner, the method performing the following steps:

detecting and grouping together one or more consecutive pixels of a current scanline having substantially similar colors;

updating a current background color having a likelihood of being a background color of the scanner, wherein the current background color is derived from previous background color and a color representative of pixels of the current scanline most likely to be part of a background color;

determining those said groups of pixels of a current scanline that are likely to belong to said images and those that are likely to belong to the background based upon said updated current background color; and

copying said determined groups of pixels belonging to images of a current scanline to their respective images.

6. A method as claimed in claim 5, wherein said step of determining said groups of pixels comprises the sub-step of:

comparing said groups of pixels of said current scanline with said updated current background color, wherein if any one of said groups of pixels are substantially similar in color to the current background color marking those groups as belonging to said background otherwise marking any one of said groups of pixels that are not substantially similar in color to the current background color as belonging to said images.

7. A method as claimed in claim 5, wherein said step of updating the current background color comprises the sub-steps of:

determining a value representative of the current background color based on a value of the previous background color, a value representative of the certainty that said updated value of the current background color will be correct, and the color of that group of pixels of the current scanline most likely as being part of the background color.

8. A method as claimed in claim 5, wherein said step of updating the current background color comprises the sub-steps of

(a) performing the following sub-steps for each of said group of pixels of the current scanline:

(a)(1) determining a value representative of the likelihood that the group of pixels belongs to the background based on the number of pixels in the group;

(a)(2) determining a value representative of the likelihood that the group of pixels belongs to the background based on the color of the pixels of the group with reference to the previously determined background color; and

(a)(3) determining a value representative of the likelihood that the group of pixels belongs to the background based on the previous likelihood values determined during steps a(1) and a(2), and a value representative of the certainty that the previously determined background color is correct;

(b) performing the following sub-steps once for the current scanline;

(b)(1) determining the maximum of the likelihood values determined by step a(3) for the groups of pixels for the current scanline;

(b)(2) setting the certainty value to said maximum value determined during step (b)(1); and

(b)(3) determining the current background color based on the color of the pixels of the group of pixels having a maximum likelihood value'"'"' determined by step (b)(1), the previously determined background color, and the certainty value set during step (b)(2); and

wherein said step of determining said groups of pixels comprises the sub-step of;

(c) comparing said groups of pixels of said current scanline with said determined current background color, wherein if any one of said groups of pixels are substantially similar in color to the current background color marking those groups as belonging to said background otherwise marking any one of said groups of pixels that are not substantially similar in color to the current background color as belonging to said images.

9. A method as claimed in claim 5, wherein said respective images are individually de-skewed, clipped and saved to disk as separate image files.

10. A method of scanning and individually copying a number of images on scanner, the method performing the following steps:

pre-processing a current scanline to provide a current pre-processed scanline wherein the current pre-processed scanline is representative of edges of a pixel image o the current scanline;

detecting and grouping together one or more consecutive pixels of the current pre-processed scanline, wherein those pixels of the current pre-processed scanline having values below a predetermined threshold value are grouped together in a group;

updating a current background color having a likelihood of being a background color of the scanner, wherein the current background color is derived from a previous background color and a color representative of a group of pixels of the current scanline corresponding to the grouped pixels of the current preprocessed scanline having values below the predetermined threshold;

determining said groups of pixels of a current scanline that are likely to belong to said images and those that are likely to belong to the background based upon said updated current background color; and

copying said determined groups of pixels belonging to images of a current scanline to their respective images.

12. Apparatus for scanning and individually copying a number of images on a scanner, the apparatus comprising;

processing means for processing a plurality of scanlines, the processing means comprising;

means for detecting and grouping together one or more consecutive pixels of a current scanline;

means for updating a current background of the scanner, wherein the current background color is derived from a previous background color and a color representative of the grouped pixels of the current scanline most likely to be part of a background;

means for determining those said groups of pixels of a current scanline that are likely to belong to said images and those that are likely to belong to the background based upon said updated current background color; and

means for copying said determined groups of pixels belonging to images of a current scanline to their respective images.

13. Apparatus as claimed in claim 12, wherein the representation of the current scanline represents the edges of a pixel image of the current scanline.

14. Apparatus as claimed in claim 12, wherein the representation of the current scanline represents a pixel image of the current scanline.

15. Apparatus for scanning and individually copying a number of images on a scanner, the apparatus comprising:

processing means for processing a plurality of scanlines, the processing means comprising;

means for updating and grouping together one or more consecutive pixels of a current scanline having substantially similar colors;

means for determining a current background color having a likelihood of being a background color of the scanner, wherein the current background color is derived from a previous background color and a color representative of the grouped pixels of the current scanline most likely to be part of a background color;

means for determining those said groups of pixels of a current scanline that are likely to belong to said images and those that are likely to belong to the background based upon said updated current background color; and

means for copying said determined groups of pixels belonging to images of a current scanline to their respective images.

16. Apparatus as claimed in claim 15, wherein said means for determining said groups of pixels comprises:

means for comparing said groups of pixels of said current scanline with said updated current background color, wherein if any one of said groups of pixels are substantially similar in color to the current background color marking those groups as belonging to said background otherwise marking any one of said groups of pixels that are not substantially similar in color to the current background colour as belonging to said images.

17. Apparatus as claimed in claim 15, wherein said means for updating the current background color comprises:

means for determining a value representative of the current background color based on a value of the previous background color, a value representative of the certainty that said updated value of the current background will be correct, and the of that group of pixels of the current scanline most likely as being part of the background.

18. Apparatus as claimed in claim 15, wherein said means for determining the current background color comprises:

processing means for processing each of said group of pixels of the current scanline, the processing means comprising;

first determination means for determining a value representative of the likelihood that the group of pixels belongs to the background based on the number of pixels in the group;

second determination means for determining a value representative of the likelihood that the group of pixels belongs to the background based on the color of

the pixels of the group with reference to the previously determined background color; and

third determination means for determining a value representative of the likelihood that the group of pixels belongs to the background based on the previous likelihood values determined by said first and second means, and a value representative of the certainty that the previously determined background color is correct;

processing means for processing the current scanline, the processing means comprising;

fourth determination means for determining the maximum of the likelihood values determined by the third determination means for the groups of pixels for the current scanline;

means for setting the certainty value to said maximum value determined by said fourth determination means; and

fifth determination means for determining the current background color based on the color of the pixels of the group of pixels having a maximum likelihood value determined by the fourth determination means, the previously determined background color, and the certainty value set by the setting means;

and wherein said means for determining said groups of pixels comprises;

means for comparing said groups of pixels of said current scanline with said determined current background color, wherein if any one of said groups of pixels are substantially similar in color to the current background color marking those groups as belonging to said background otherwise marking any one of said groups of pixels that are not substantially similar in color to the current background color as belonging to said images.

19. Apparatus as claimed in claim 15, wherein said respective images are individually de-skewed, clipped and saved to disk as separate image files.

20. Apparatus for scanning and individually copying a number of images on a scanner, the apparatus comprising:

processing means for processing a plurality of scanlines, the processing means comprising;

means for pre-processing a current scanline to provide a current preprocessed scanline, wherein the current pre-processed scanline is representative of edges of a pixel image of the current scanline;

means for detecting and grouping together one or more consecutive pixels of the current pre-processed scanline, wherein those pixels of the current preprocessed scanline having values below a predetermined threshold value are grouped together in a group;

means for updating a current background color having a likelihood of being a background color of the scanner, wherein the current background color is derived from a previous background color and a color representative of a group of pixels of the current scanline corresponding to the grouped pixels of the current pre-processed scanline having values below the predetermined threshold;

means for determining said groups of pixels of a current scanline that are likely to belong to said images and those that are likely to belong to the background based upon said updated current background color; and

means for copying said determined groups of pixels belonging to images of a current scanline to their respective images.

21. A computer readable medium encoded with a computer program for scanning and individually detecting a number of images on a scanner, the computer program comprising:

processing means for processing a plurality of scanlines, the processing means comprising;

means for detecting and grouping together one or more consecutive pixels of a current scanline, wherein the pixels are grouped together based on a representation of said current scanline;

means for updating a current background color of the scanner, wherein the current background color is derived from a previous determined background color and a color representative of the grouped pixels of the current scanline most likely to be part of a background;

means for determining those said groups of pixels of a current scanline that are likely to belong to said images and those that are likely to belong to the background based upon said updated current background color; and

means for copying said determined groups of pixels belonging to images of a current scanline to their respective images.

22. A computer readable medium encoded with a computer program for scanning and individually detecting a number of images on a scanner, the computer program comprising:

processing means for processing a plurality of scanlines, the processing means comprising;

means for detecting and grouping together one or more consecutive pixels of a current scanline having substantially similar colors;

means for updating a current background color having a likelihood of being a background color of the scanner, wherein the current background color is derived from a previous background color and a color representative of pixels of the current scanline most likely to be part of the background color;

means for determining said groups of pixels of a current scanline that are likely to belong to said images and those that are likely to belong to the background based upon said updated current background color; and

means for copying said determined groups of pixels belonging to images of a current scanline to their respective images.

23. A computer readable medium encoded with a computer program for scanning and individually detecting a number of images on a scanner, the computer program comprising:

processing means for processing a plurality of scanlines, the processing means comprising;

means for pre-processing a current scanline to provide a current preprocessed scanline, wherein the current pre-processed scanline is representative of edges of a pixel image of the current scanline;

means for detecting and grouping together one or more consecutive pixels of the current pre-processed scanline, wherein those pixels of the current preprocessed scanline having values below a predetermined threshold value are grouped together in a group;

means for updating a current background color having a likelihood of being a background color of the scanner, wherein the current background color is derived from a previous background color and a color representative of pixels of the current scanline corresponding to the said group of pixels of the current pre-processed scanline having values below the predetermined threshold;

means for determining said groups of pixels of a current scanline that are likely to belong to said images and those that are likely to belong to the background based upon said updated current background color; and

means for copying said determined groups of pixels belonging to images of a current scanline to their respective images.