Method of scanning regions larger than the scan swath using a handheld scanner
A method of swipe-scanning a graphic image pre-printed on a surface. The method comprises the steps of: (i) operatively positioning a swipe scanner relative to the surface and swiping the scanner across the surface; (ii) capturing, during the swipe, successive images of portions of the graphic image; (iii) printing, during the swipe, successive parts of a position-coding pattern onto the surface, the position-coding pattern being superimposed with the graphic image; (iv) imaging, during the swipe, portions of the surface on which the printhead has printed the parts of the position-coding pattern; (v) determining absolute positions of the scanner using the imaged parts of the position-coding pattern; and (vi) using the absolute positions to assemble the captured portions of the graphic image into a scanned graphic image.
1. A method of swipe-scanning and printing onto a graphic image pre-printed on a surface, said method comprising the steps of:
(i) operatively positioning a scanner relative to the surface and swiping the scanner across the surface, said scanner having a scanhead and a printhead;
(ii) capturing, during said swipe, successive images of portions of the graphic image using said scanhead;
(iii) printing, during said swipe, successive parts of a position-coding pattern onto the surface using said printhead, said position-coding pattern being superimposed with said graphic image;
(iv) imaging, during said swipe, portions of said surface on which said printhead has printed said parts of the position-coding pattern;
(v) determining absolute positions of the scanner using the imaged parts of the position-coding pattern;
(vi) sensing an orientation of the scanner relative to the position-coding pattern; and
(vii) using the orientation together with said absolute positions to assemble said captured portions of said graphic image into a scanned graphic image.
2. The method of claim 1 , wherein an initial position of said scanner provides a reference point for said position-coding pattern.
3. The method of claim 2 , wherein said reference point is an origin.
4. The method of claim 3 , wherein said origin is based on an assumed initial swipe direction in step (i).
5. The method of claim 4 , wherein said origin is a top-left corner of the position-coding pattern, and said initial swipe direction is a left-to-right swipe or a top-to-down swipe.
6. The method of claim 1 , wherein step (i) further comprises the sub-steps of:
imaging part of a position-coding pattern printed during a previous swipe of the scanner; and
determining an absolute position of the scanner,
wherein said imaged part of the position-coding pattern is contained in an outer perimeter of the position-coding pattern printed during the previous swipe.
7. The method of claim 6 , wherein said swiping comprises swiping outwardly from said outer perimeter of said pre-printed position-coding pattern.
8. The method of claim 1 , wherein said graphic image is printed with at least one first ink and said position-coding pattern is printed with a second ink.
9. The method of claim 8 , wherein said second ink is an infrared-absorbing ink.
10. The method of claim 9 , wherein the or each first ink has an infrared window enabling imaging of said position-coding pattern in the presence of the first ink.
11. The method of claim 1 , wherein said scanner is configured for unidirectional swiping.
12. The method of claim 11 , wherein said scanner comprises a first image sensor for imaging said position-coding pattern, said first image sensor being positioned downstream of a printhead, wherein a swipe direction is defined as upstream.
13. The method of claim 1 , further comprising the steps of:
sensing relative motion of the scanner during the swipe to generate relative motion data; and
using the relative motion data together with said absolute positions to assemble said scanned graphic image.
14. The method of claim 1 , further comprising the steps of:
accessing an impression identity for said graphic image;
associating said impression identity with said graphic image;
generating association data indicating an association between the impression identity, the absolute positions and the graphic image; and
communicating said association data to a computer system.
15. The method of claim 14 , wherein the printed position-coding pattern further identifies said impression identity.
16. The method of claim 15 , wherein said interactive element is selected from the group comprising: a hyperlink, an input field and a button.
17. The method of claim 14 , wherein said association data enables said computer system to associate one or more zones of the graphic image with a corresponding interactive element.
18. The method of claim 14 , wherein said impression identity is accessed from any one of:
a memory in said scanner, said memory storing a plurality of impression identities; and
a computer system communicating with said scanner.
19. The method of claim 1 , wherein said scanner is contained in a mobile phone or personal digital assistant.