Method and apparatus for reading a printed indicia with a limited field of view sensor

• US 20080245869A1
• Filed: 03/24/2008
• Published: 10/09/2008
• Est. Priority Date: 03/23/2007
• Status: Abandoned Application

• Current Assignee: LTT Limited
• Original Assignee: LTT Limited
• Inventors: Keenan, Peter B., Felsenstein, Lee, Berkun, Kenneth
• Application Number:
  US12/079,241
• Publication Number:
  US 20080245869A1
• Time in Patent Office: Days
• US Class Current: 235/462.1
• CPC Class Codes: G06K 19/06037 multi-dimensional coding
• CPC Class Codes: G06K 7/14 using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G06K 7/1491 the method including a reconstruction step, e.g. stitching two pieces of bar code together to derive the full bar code

Abstract

A 2D matrix symbol may be formed by dividing data into a plurality of segments, separately encoding the plurality of segments as corresponding arrays of cells, and arranging the arrays of cells in an abutting relationship. A segmented 2D symbol may be read by capturing a plurality of images of a 2D matrix bar code symbol that is not subtended by any of the images and reconstructing at least some of the plurality of images to a portion of the 2D symbol or 2D symbol data larger than any of the images.

Claims

1. A method for making a bar code symbol comprising:

dividing data into a first plurality of segments;

separately encoding a second plurality of the segments as corresponding arrays of cells; and

arranging the arrays of cells in an abutting relationship.

2. The method of claim 1 wherein the first and second pluralities are equal.

3. The method of claim 1 wherein arranging the arrays of cells in an abutting relationship includes forming a bitmap of the arrays of cells.

4. The method of claim 1 wherein arranging the arrays of cells in an abutting relationship includes printing the arrays of cells.

5. The method of claim 1 further comprising:

bitmapping at least one framing feature selected from the group consisting of at least one finder pattern, at least one clocking pattern, at least one indexing pattern, and at least one segment identifier; and

wherein arranging the arrays of cells in an abutting relationship includes arranging the at least one framing feature and the arrays of cells in an abutting relationship.

6. The method of claim 1 further comprising:

bitmapping at least one framing feature selected from the group consisting of at least one finder pattern, at least one clocking pattern, at least one indexing pattern, and at least one segment identifier; and

wherein arranging the arrays of cells in an abutting relationship includes inserting the at least one framing feature between the abutting arrays of cells.

7. The method of claim 1 further comprising:

encoding a third plurality of segment identification fields corresponding to the arrays of cells;

wherein the third plurality is equal to the second plurality or the second plurality plus one.

8. The method of claim 1 further comprising:

encoding a third plurality of segment identification fields corresponding to the arrays of cells; and

arranging the third plurality of segment identification fields amongst the arrays of cells in the abutting relationship.

9. The method of claim 1 further comprising:

encoding a third plurality of segment identification fields corresponding to the arrays of cells; and

arranging the third plurality of segment identification fields relative to the arrays of cells in the abutting relationship;

wherein a correspondence between a particular segment identification field and its corresponding array of cells is determined according to the relative placement of the particular segment identification field and its corresponding array of cells.

10. The method of claim 1 wherein the data corresponds to an audio file or a video file.

11. The method of claim 1 wherein the segments are each of substantially equal size.

12. The method of claim 1 further comprising:

receiving an audio or video signal; and

converting the audio or video signal to the data.

13. The method of claim 1 wherein the first plurality is equal to the second plurality.

14. The method of claim 1 performed by computer execution of computer instructions received on a computer readable medium.

15. The method of claim 1 wherein the arrays of cells form at least a portion of a 2D matrix bar code symbol.

16. The method of claim 1 further comprising:

encoding a plurality of Gray Code segment identification fields corresponding to the arrays of cells.

17. A method for reading a segmented bar code symbol comprising:

capturing a plurality of images of a 2D matrix bar code symbol that is not subtended by any of the images; and

reconstructing at least some of the plurality of images to a portion of the 2D symbol or 2D symbol data larger than any of the images.

18. The method of claim 17 wherein reconstructing at least some of the plurality of images to a portion of the 2D symbol or 2D symbol data larger than any of the images includes:

combining data corresponding to the plurality of images.

19. The method of claim 17 further comprising:

determining at least one segment value corresponding to a plurality of the captured images; and

determining a relationship between the captured images from the segment value or values.

20. The method of claim 17 further comprising:

determining a location of or decoding a segment identification field.

21. The method of claim 17 further comprising:

determining a location of or decoding a segment identification field using at least one selected from the group consisting of;

performing a plurality of computational methods, image processing, performing a Fourier transform, a phase mask, a chipping sequence, a chipping sequence along an axis, pattern matching in the image domain, pattern matching in the frequency domain, finding bright spots in the frequency domain, synthesizing data from a neighboring data segment, pseudo-decoding data from a neighboring data segment, a finder pattern, finding parallel edges, finding a finder pattern, centers decoding, image resolution using a priori knowledge of symbol structure, closure decoding, edge finding, uniform acceleration compensation, surface de-warping, anti-aliasing, frame transformation, frame rotation, frame de-skewing, keystone correction, Gray Code, pattern phase, phase comparison, delta distance, local thresholding, global thresholding, modulation compensation, image inversion, inverted image projection, and sampling image regions positioned relative to a finder.

22. The method of claim 17 further comprising:

determining a location of or decoding a segment identification field;

and wherein the correspondence of the segment identification field to its corresponding data field is determined according to a geometric relationship between the two.

23. The method of claim 17 further comprising:

determining a location of at least two segment identification fields; and

wherein a logical relationship between the at least two segment identification fields corresponds to a geometric relationship between the at lest two segment identification fields.

24. The method of claim 17 wherein the 2D symbol is larger in extent than any one of the images.

25. The method of claim 17 further comprising:

caching the reconstructed 2D symbol or symbol data portion; and

comparing an additional image or an additional set of image data to the cached reconstructed 2D symbol or symbol data portion to determine if the additional image or additional image data includes a data segment not present in the cached reconstructed symbol or symbol data portion.

26. The method of claim 17 further comprising:

caching the reconstructed 2D symbol or symbol data portion; and

comparing an additional image or an additional set of image data to the cached reconstructed 2D symbol or symbol data portion to determine if the additional image or additional image data includes a data segment not present in the cached reconstructed symbol or symbol data portion; and

combining the additional image or image data with the cached reconstructed 2D symbol or symbol data portion if the additional image or image data includes a data segment not present in the cached reconstructed symbol or symbol data portion.

27. The method of claim 26, wherein the cached reconstructed 2D symbol or symbol data portion includes an image of the 2D symbol portion;

and wherein the additional image or image data includes an additional image.

28. The method of claim 26, wherein the cached reconstructed 2D symbol or symbol data portion includes segment data received in the at least two different of the plurality of images;

and wherein the additional image or image data includes data corresponding to an additional segment.

29. The method of claim 17 further comprising:

outputting data corresponding to the reconstructed 2D symbol or symbol data.

30. The method of claim 29 wherein outputting data includes at least one selected from the group consisting of writing the data to a disk drive, saving the data in a file, playing an audio file, and playing a video file.

31. A 2D matrix symbol comprising:

at least two segment identification fields; and

at least two separately decodable data segment fields, each corresponding to one or more of the segment identification fields.

32. The 2D matrix symbol of claim 31 wherein the segment identification fields are printed near but not integrated into the data segments.

33. The 2D matrix symbol of claim 31 wherein a relationship between one of the segment identification fields and its corresponding data field is established by a geometric relationship between the cells of the one segment identification field and its corresponding data segment field.

34. The 2D matrix symbol of claim 31 wherein the at least two segment identification fields include respective Gray Codes.

35. The 2D matrix symbol of claim 31 wherein one of the segment identification fields identifies an end of a last data segment and the other segment identification fields identify the start of each corresponding data segment.

36. A system configured to read a 2D matrix symbol comprising:

an image capture module configured to successively capture images corresponding to first portions less than the entirety of a 2D matrix symbol; and

a processor operatively coupled to the image capture module and configured to reconstruct the images into a second portion of data or cells of the 2D matrix symbol larger than either of the first portions.

37. The system of claim 36 wherein the processor is configured to decode or synthesize segment identification fields from the images.

38. The system of claim 36 wherein the processor is configured to decode or synthesize segment identification fields from the images and reconstruct corresponding data segments or data field segments from the images into a second portion of data or cells of the 2D matrix symbol in an order corresponding to the values of the respective segment identification fields.

39. The system of claim 36 further comprising an output interface configured to play an audio or video file from data decoded from the second portion of the 2D matrix symbol.

40. The system of claim 36 wherein the processor is disposed in a computer and the image capture module is configured to transmit a signal to the computer carrying the successively captured images.

41. The system of claim 36 wherein the image capture module and the processor are portions of a single apparatus.

42. The system of claim 36 further comprising a user input interface operatively coupled to the processor and configured to receive a command to begin capturing images.

43. The system of claim 36 wherein the processor is further configured to decode separately decodable data segments in the 2D matrix symbol.

44. The system of claim 36 wherein the processor is configured to decode segment identification fields from the images using at least one selected from the group consisting of:

performing a plurality of computational methods, image processing, performing a Fourier transform, a phase mask, a chipping sequence, a chipping sequence along an axis, pattern matching in the image domain, pattern matching in the frequency domain, finding bright spots in the frequency domain, synthesizing data from a neighboring data segment, pseudo-decoding data from a neighboring data segment, a finder pattern, finding parallel edges, finding a finder pattern, centers decoding, image resolution using a priori knowledge of symbol structure, closure decoding, edge finding, uniform acceleration compensation, surface de-warping, anti-aliasing, frame transformation, frame rotation, frame de-skewing, keystone correction, Gray Code, pattern phase, phase comparison, delta distance, local thresholding, global thresholding, modulation compensation, image inversion, inverted image projection, and sampling image regions positioned relative to a finder.

45. A system configured to output a 2D matrix symbol comprising:

a memory configured to receive data;

a processor operatively coupled to the memory and configured to divide data into a plurality of segments, separately encode the plurality of the segments as corresponding arrays of cells forming data field segments, and arrange a bitmap the arrays of cells in an abutting relationship in the memory.

46. The system of claim 45 further comprising:

a printer operatively coupled to the processor to receive the bitmap from the memory and print a label corresponding to the bitmap.

47. The system of claim 45 wherein the processor if further configured to bitmap at least one framing feature selected from the group consisting of at least one finder pattern, at least one clocking pattern, at least one indexing pattern, and at least one segment identifier;

and

arrange the arrays of cells in the abutting relationship along with the at least one framing feature.

48. The system of claim 45 wherein the processor is further configured to encode a plurality of segment identification fields corresponding to the arrays of cells and to include the segment identification fields in the bitmap.

49. The system of claim 45 wherein the processor is further configured to encode a plurality of segment identification fields corresponding to the arrays of cells and to include the segment identification fields in the bitmap at bitmap locations selected to provide a geometric relationship between each segment identification field and its corresponding data field segment.

50. The system of claim 45 wherein the data corresponds to an audio file or a video file.

51. The system of claim 45 further comprising:

an interface configured to receive an audio or video signal; and

wherein the processor is further configured to convert the audio or video signal to the data.

52. The system of claim 45 wherein the processor is further configured to encode a plurality of Gray Code segment identification fields corresponding to the arrays of cells and to include the segment identification fields in the bitmap.

53. A computer readable medium carrying computer executable instructions to receive a plurality of images of a 2D matrix bar code symbol that is not subtended by any of the images;

and

reconstruct at least some of the plurality of images to a portion of the 2D symbol or 2D symbol data larger than any of the images.

54. A computer readable medium carrying computer executable instructions for performing processing comprising:

dividing data into a first plurality of segments;

separately encoding a second plurality of the segments as corresponding arrays of cells; and

arranging the arrays of cells in an abutting relationship.