Two-dimensional code having rectangular region provided with specific patterns for specify cell positions and distinction from background

• US 20090242649A1
• Filed: 03/26/2009
• Published: 10/01/2009
• Est. Priority Date: 03/27/2008
• Status: Active Grant

• Current Assignee: Denso Wave Inc (DENSO Corporation)
• Original Assignee: Denso Wave Inc (DENSO Corporation)
• Inventors: Ito, Yuichi, Tanaka, Masami, Hara, Masahiro, Kita, Hayato, Ushijima, Takao, Mizukoshi, Hiroaki
• Granted Patent: US 8,235,303 B2
• Time in Patent Office: Days
• US Class Current: 235/494
• CPC Class Codes: G06K 19/06037 multi-dimensional coding
• CPC Class Codes: G06K 19/06046 Constructional details
• CPC Class Codes: G06K 19/06075 the marking containing means for error correction

Abstract

A two-dimensional code having a rectangular region is provided. In the rectangular region, there are code blocks composed of a plurality of cells, a first specific pattern specifying the positions of the cells, and a second specific pattern separating the code blocks from a background of the code. The first specific pattern is located at a specified corner of the rectangular region. The second specific pattern is located along one or more of first borders along which the first specific pattern is located, the first borders being part of the borders of the rectangular region. The code blocks include error-correction code blocks, which are located along second borders which are different from a border of the borders along which the second specific pattern is located. The second borders are part of the borders. Compressed data code blocks are also arranged in the same way as the error-correction code blocks.

Claims

1. A two-dimensional code having a rectangular region delineated from a background by a plurality of borders, comprising:

code blocks each composed of a plurality of cells which are aggregated;

a first specific pattern used to specify the positions of the cells; and

a second specific pattern used to distinguish the code blocks from a background of the code,

wherein the code blocks, the first specific pattern and the second specific pattern are arranged in the rectangular region,

the first specific pattern is located at a specified corner of the rectangular region,

the second specific pattern is located along one or more of first borders along which the first specific pattern is located, the first borders being part of the borders of the rectangular region,

the code blocks include error-correction code blocks for correcting an error, and

the error-correction code blocks are located along second borders which are different from a border of the borders along which the second specific pattern is located, the second borders being part of the borders of the rectangular region.

3. The two-dimensional code of claim 1, wherein one or more of the error-correction code blocks are arranged along each of the second borders.

5. The two-dimensional code of claim 1, wherein the code blocks include a first border block arranged along between the first specific pattern and the second specific pattern along the first borders, and

the first border block includes the error-correction code blocks.

7. The two-dimensional code of claim 1, wherein the respective cells of the error-correction code blocks are colored and the respective cells of data code blocks of which errors are corrected by the error-correction code blocks are colored, a combination of the colors for the cells of the error-correction code blocks being different from a combination of the colors for the cells of the data code blocks of which errors are corrected by the error-correction code blocks.

9. The two-dimensional code of claim 1, comprising a third specific pattern arranged along part of the second borders to distinguish the code blocks from the background,

wherein the error-correction code blocks and the third specific pattern are arranged along the second borders.

11. The two-dimensional code of claim 9, wherein the third specific pattern has a plurality of cells different in saturation, hue, or lightness from each other and arranged in a predetermined order.

12. The two-dimensional code of claim 9, wherein the third specific pattern and the second specific pattern are the same in shape.

13. The two-dimensional code of claim 1, wherein the rectangular region is a square region composed of a matrix whose one side is composed of odd-number L of cells so that a matrix size thereof is L×

L, the first specific pattern has a contour which is a square composed of a matrix whose one side is composed of odd-number M of cells M (M<

L) so that a matrix size thereof is M×

M, the second specific pattern is a linear pattern composed of even-number N of cells satisfying N=L−

M and being lined up, and each of the code blocks is composed of a rectangular matrix having a matrix size of A×

B, whose one side is composed of even-number A of cells lined up and whose the other side is composed of even-number B of cells lined up.

14. The two-dimensional code of claim 1, wherein the second specific pattern includes a plurality of cells, at least, whose saturation, hue, or lightness differs from each other.

15. The two-dimensional code of claim 1, wherein the rectangular region has a second corner positionally different from the first corner,

the second specific pattern includes a first end pattern arranged at the second corner of the rectangular area.

16. The two-dimensional code of claim 15, wherein the second specific pattern is composed of the first end pattern.

17. The two-dimensional code of claim 15, wherein the first end pattern is a liner pattern composed of a plurality of cells which are continuously lined up and which are the same in saturation, hue, or lightness.

18. The two-dimensional code of claim 15, wherein the first end pattern is a liner pattern composed of a plurality of cells which are lined up in a predetermined order and which are different from each other in saturation, hue, or lightness.

19. The two-dimensional code of claim 15, wherein the first end pattern is an L-shaped pattern composed of a plurality of cells which are continuously arranged and which are the same in saturation, hue, or lightness.

20. The two-dimensional code of claim 15, wherein the first end pattern is an L-shaped pattern composed of a plurality of cells different in saturation, hue, or lightness from each other and arranged in a predetermined order.

21. The two-dimensional code of claim 15, wherein the first end pattern is composed of a single cell whose saturation, hue, or lightness is different from the background.

22. The two-dimensional code of claim 15, wherein the error-correction code blocks or a residual block is arranged around the first end pattern, the residual block storing therein a residual cell which is not allocated to the data code blocks storing data.

23. The two-dimensional code of claim 1, wherein

the code blocks include the error-correction code blocks for correcting an error, and

the error-correction code blocks are arranged adjacently to the second specific pattern arranged along the first borders.

24. The two-dimensional code of claim 1, wherein

the code blocks include the compressed data code blocks in which the compressed data are stored,

the second specific pattern arranged along the first borders has an inner side, and

the compressed data code blocks are arranged adjacently to the inner side of the second specific pattern.

25. The two-dimensional code of claim 1, comprising a second end pattern arranged at a corner of the rectangular region which is diagonally located to the first specific pattern in the rectangular region.

26. The two-dimensional code of claim 25, wherein the second end pattern is an L-shaped pattern composed of a plurality of cells which are continuously arranged and which are the same in saturation, hue, or lightness.

27. The two-dimensional code of claim 25, wherein the second end pattern is an L-shaped pattern composed of a plurality of cells different in saturation, hue, or lightness from each other and arranged in a predetermined order.

28. The two-dimensional code of claim 25, wherein the second end pattern includes a first cell having a given saturation, hue, or lightness and second cells which are different in saturation, hue, or lightness from the first cell, the second cells being arranged to enclose the first cell so that the second end pattern is rectangular.

29. The two-dimensional code of claim 25, wherein the rectangular region is a region in which a plurality of types of cells are arranged which are different in saturation, hue, or lightness from each other, and

the second end pattern is composed of a plurality of types of cells which are different in saturation, hue, or lightness from each other and which are arranged in a combination of given types of cells and serves as reference region for making reference to a type of the rectangular region.

30. The two-dimensional code of claim 1, wherein the rectangular region is a region in which a plurality of types of cells are arranged which are different in saturation, hue, or lightness from each other, and

the second specific pattern is composed of a plurality of types of cells which are different in saturation, hue, or lightness from each other and which are arranged in a combination of given types of cells and serves as a reference region for making reference to a type of the rectangular region.

31. The two-dimensional code of claim 1, wherein specific types of cells among the cells of, at least, any one of the first specific pattern, the second specific pattern, and the code blocks have a shape other than a rectangular shape.

32. The two-dimensional code of claim 31, wherein the specific types of cells in both the first specific pattern and the second specific pattern have a quadrangular shape categorized as the rectangular shape and the specific type of cells in the code blocks have the shape other than the quadrangular shape.

33. The two-dimensional code of claim 31, wherein the specific types of cells are different in saturation, hue, or lightness than the background, and

the specific type of cells in the code blocks have a pattern area composing the shape other than the quadrangular shape and differ in saturation, hue, or lightness from the background,

wherein the pattern area is located at or close to a border of each cell area of the specific types of cells.

34. The two-dimensional code of claim 1, comprising a pattern insertion area arranged in the rectangular region, a pattern different from the cells is inserted into the rectangular region,

wherein the pattern insertion area is larger than the size of the cells and is arranged to be over a plurality of cell positions in the code blocks.

35. The two-dimensional code of claim 34, wherein the pattern insertion area has a border of which entire portion is different in at least one of saturation, hue, or lightness from cells adjacent to the pattern insertion area, the cells adjacent to the pattern insertion area being part of the cells of the code.

36. The two-dimensional code of claim 34, wherein part of the pattern insertion area partly composes the borders of the rectangular region.

37. The two-dimensional code of claim 34, wherein the pattern insertion area is arranged to overlap with the code blocks,

respective cell areas of the code blocks on which the pattern insertion area is overlapped is identifiable, at least, in part of the pattern insertion area, and

the respective identifiable cell areas are configured in a mode which corresponds to data to be shown by the respective cell areas.

38. The two-dimensional code of claim 1, comprising a pattern portion composed of patterns different from the cells and arranged to be over a plurality of cell positions in the code blocks.

39. The two-dimensional code of claim 38, wherein all borders of the pattern portion are different in, at least, one of saturation, hue, or lightness from, of the cells, cells adjacent to the borders of the pattern portion.

40. The two-dimensional code of claim 38, wherein the pattern portion is arranged to be over the inside and an outside of the rectangular region.

41. The two-dimensional code of claim 38, wherein the pattern portion is arranged to overlap with the code blocks,

respective cell areas of the code blocks on which the pattern portion is overlapped is identifiable, at least, in part of the pattern portion, and

the respective identifiable cell areas are configured in a mode which corresponds to data to be shown by the respective cell areas.

42. The two-dimensional code of claim 1, wherein the code blocks are expressed by the cells composed of X types and Y pieces of cells which are composed of composite data produced by adding, to data to be decoded having an information amount of N bits in binary number, error-detection data having an information amount of M bits in binary number, the composite data satisfying a relationship of X^Y−

1<

2^N×

2^M<

X^Y.

43. The two-dimensional code of claim 1, comprising an end pattern arranged at a corner of the rectangular region which positionally differs from the specified corner of the rectangular region,

wherein the end pattern is previously given inherent length ratios corresponding to every size of the two-dimensional code, the inherent length ratios each providing the end pattern with a ratio between a longitudinal length thereof and a lateral length thereof.

44. The two-dimensional code of claim 43, wherein the inherent length ratio for each size of the two-dimensional code is predetermined such that a sum of C1 and C2 becomes larger with an increase in the inherent length ratio, wherein C1 and C2 are natural numbers both changeable every size of the two-dimensional code.

45. The two-dimensional code of claim 43, wherein the end pattern is composed of cells arranged in an L shape along borders of the corner of the rectangular region which positionally differs from the specified corner thereof.

46. The two-dimensional code of claim 1, wherein the code blocks include data code blocks in which encoded data are stored, the data being expressed by a plurality of digits of symbols composed of a plurality of types of symbols,

the encoded data satisfy a relationship of 2^F−

1<

D^E<

2^F, wherein D denotes the number of types of the symbols and E and F are natural numbers, and

the data code blocks express a string of bits which are binary-converted every E-digit that provides a bit conversion rate F/E with a given lower value.

47. The two-dimensional code of claim 46, wherein the given lower value is set so that the bit conversion rate F/E has the lowest value thereof.

48. The two-dimensional code of claim 46, wherein

the data code blocks express the string of bits which are binary-converted every E1 digits and residual digits of less than the E1 digits in the string of bits are binary-converted every E2 digits, wherein E1 denotes a value of the number of digits, E, obtained when the bit conversion rate F/E is the smallest and E2 denotes a value of the number of digits, E, obtained when the bit conversion rate F/E is next in smallness to the value E1 (0<

E2<

E1).

49. The two-dimensional code of claim 1, wherein the cells composing the code blocks include a plurality of cells which are the same kind with each other and arranged into a rectangular form to produce a large basic cell unit whose size is larger than the size of each of the cells, and the first specific pattern is composed of a combination of a plurality of the large basic cell units.

50. The two-dimensional code of claim 49, wherein the second specific pattern is composed of a combination of a plurality of cells each of which is the large basic cell unit.

51. The two-dimensional code of claim 49, wherein the larger basic cell unit and the cells composing the code blocks are analogous in shape to each other.

52. The two-dimensional code of claim 49, comprising a format information block indicating format information of the two-dimensional code and being composed of a plurality of cells each of which is the large basic cell unit.

53. The two-dimensional code of claim 52, wherein the format information block is arrange adjacently to, at least, one of the first specific pattern or the second specific pattern.

54. The two-dimensional code of claim 49, wherein each of the first specific pattern and the second specific pattern is composed of a combination of a plurality of cells each of which is the large basic cell unit, and

all of the respective large basic cell units composing the first specific pattern, the second specific pattern, and the format information block are the same in their sizes.

55. The two-dimensional code of claim 1, wherein the data blocks include a first data code block expressing a first data of a predetermined type and a second data code block expressing a second data which is different in type from the first data, and

the first data code block is arranged in a first area arranged in the code and the second data code block is arranged in a second area arranged in the code, the second area being positionally farther than the first area from the first specific pattern.

56. The two-dimensional code of claim 55, wherein each of the first data and the second data is given an error correction level, the error correction level of the first data being higher than that of the second data.

57. The two-dimensional code of claim 55, wherein the first data indicates format information and the second data indicates information other than the format information.

58. The two-dimensional code of claim 1, comprising a second two-dimensional code arranged in the rectangular region and formed to be smaller in size than the rectangular region,

wherein the code blocks provide information expressed by a plurality of display colors including chromatic colors, and

the second two-dimensional code provides information expressed by a plurality of types of achromatic colors.

59. The two-dimensional code of claim 1, comprising a second two-dimensional code arranged in the rectangular region and formed to be smaller in size then the rectangular region,

wherein the code blocks provide information expressed by a plurality of types of achromatic colors, and

the second two-dimensional code provides information expressed by a plurality of display colors including chromatic colors.

60. The two-dimensional code of claim 56, wherein the second two-dimensional code is arranged at an area in the rectangular region, the area being set to undergo error correction using the error-correction code blocks.

61. The two-dimensional code of claim 1, wherein the code blocks are subjected to a masking process performed using a prescribed one type of mask pattern.

62. A method of producing a two-dimensional code according to claim 1 using an image processor, comprising steps of:

acquiring object data to be encoded;

deciding cell configurations and arrangement positions of the first and second specific patterns so that the specific patterns are produced; and

deciding cell configurations and arrangement positions of the code blocks using the acquired object data so that the code blocks are produced, wherein the object data are divided into data having an information amount of binary N bits and each of the divided object data is added by error detection data having an information amount of binary M bits so that composite data are produced, and the cell configurations and the arrangement positions of each of the code blocks are decided such that the composite data are expressed by X-type and Y-piece cells that satisfy a relationship of X<sup>Y−

1</sup><

2^N×

2^M<

X^Y.

63. A program stored in a memory and readable by a computer provided with a display whose display screen displays a two-dimensional code according to claim 1, the program allowing the computer to perform steps including a step of:

displaying on the display the two-dimensional code, the displaying step including a step of displaying a dynamic pattern image in a display area of the two-dimensional code, the dynamic pattern image being different in displayed contents from the cell.

64. The program of claim 63, wherein the step of displaying the dynamic pattern image allows the dynamic pattern image to be displayed in an area of the display area, which is different from an area in which the first and second specific patterns are displayed.

65. The program of claim 63, wherein the step of displaying the two-dimensional code includes a step of displaying the two-dimensional image as part of a dynamic image, and

the step of displaying the dynamic pattern image maintains, for a given period of time or a period of time longer than the given period of time, the displayed state of the two-dimensional code that has been displayed as part of the dynamic image

66. A method of producing a two-dimensional code according to claim 1, the method including steps of:

acquiring object data to be encoded;

deciding cell configurations and arrangement positions of the first and second specific patterns so that the specific patterns are produced; and

deciding cell configurations and arrangement positions of the code blocks using the acquired object data so that the code blocks are produced,

calculating ratios of both bright cells and dark cells to be arranged in the rectangular region using not only the produced first and second specific patterns but also the produced code blocks;

determining whether or not the ratio of the dark cells in the rectangular region is larger than the ratio of the bright cells in the rectangular region based on the calculated ratios; and

mutually inverting the bright cells and the dark cells in the rectangular region when the ratio of the dark cells is larger than the ratio of the bright cells.

67. The method of claim 66, wherein the inverting step also mutually inverts bright cells and dark cells arranged in a marginal region adjacently surrounding the rectangular region.

2. A two-dimensional code having a rectangular region delineated from a background by a plurality of borders, comprising:

code blocks each composed of a plurality of cells which are aggregated;

a first specific pattern used to specify the positions of the cells; and

a second specific pattern used to distinguish the code blocks from a background of the code,

wherein the code blocks, the first specific pattern and the second specific pattern are arranged in the rectangular region,

the first specific pattern is located at a specified corner of the rectangular region,

the second specific pattern is located along one or more of first borders along which the first specific pattern is located, the first borders being part of the borders of the rectangular region,

the code blocks include compressed data code blocks in which compressed data are stored, and

the compressed data code blocks are arranged along second borders which are different from a border of the borders along which the second specific pattern is located, the second borders being part of the borders of the rectangular region.

4. The two-dimensional code of claim 2, wherein the compressed data code blocks are arranged along each of the second borders by one or more.

6. The two-dimensional code of claim 2, wherein the code blocks include a first border block arranged along between the first specific pattern and the second specific pattern along the first borders, and

the first border block includes the compressed data code blocks.

8. The two-dimensional code of claim 2, wherein the respective cells of the compressed data code blocks are colored and the respective cells of error-correction code blocks to correct the compressed data code blocks are colored, a combination of the colors of the cells of the compressed data code blocks being different from a combination of the colors of the cells of the error-correction code blocks.

10. The two-dimensional code of claim 2, comprising a third specific pattern arranged along part of the second borders to distinguish the code blocks from the background,

wherein the compressed data code blocks arranged along the second borders are arranged to positionally avoid the third specific pattern.