초록 ▼

Coordinate positions of four points are detected from a captured two-dimensional code image. The two-dimensional code size and coefficients of equations are determined for coordinate positions corresponding to center positions of respective cells compensated for inclination of the image by adding de

Coordinate positions of four points are detected from a captured two-dimensional code image. The two-dimensional code size and coefficients of equations are determined for coordinate positions corresponding to center positions of respective cells compensated for inclination of the image by adding depth information. The coordinate positions of respective cell center positions are determined according to the calculation equations by applying the determined coefficients. Brightness/darkness is discriminated from image data corresponding to the respective cell center positions and binary data (0 or 1) for respective cells are generated. Two-dimensional code information is reproduced based on the binary data. The equations are expressed by recurrence formulas. The coefficients determined from the coordinate positions are divided by the same constant to make them integers.

대표청구항 ▼

1. A two-dimensional code reading method comprising processing steps of:acquiring an image of a two-dimensional matrix code composed of a number of cells arranged in vertical and horizontal directions to form a matrix of the cells each representing binary coded data,deciding a two-dimensional matrix

1. A two-dimensional code reading method comprising processing steps of:acquiring an image of a two-dimensional matrix code composed of a number of cells arranged in vertical and horizontal directions to form a matrix of the cells each representing binary coded data,deciding a two-dimensional matrix code area in the image, and setting inspection lines identifying a center position of each of the cells, said inspection lines each joining two paired opposites of four sides defining a boundary of the decided two-dimensional matrix code area and reproducing information of the two-dimensional matrix code based on the inspection lines set by the inspection line setting processing,wherein coefficient in image position calculating equations for calculating coordinate positions of center positions of respective cells in the two-dimensional matrix code compensated for image inclination by adding inclination information for the two-dimensional matrix code re calculated for setting the inspection lines on the two-dimensional matrix code image based on coordinate positions of four points within the two-dimensional matrix code area decided by the two-dimensional matrix code area deciding step. 2. The two-dimensional code reading method as defined in claim 1, wherein each of the image position calculating equations to determining the coordinate positions of the center positions of he respective cells in the two-dimensional matrix code image is expressed by a recurrence formula with respect to a center position of each of the cells to reduce a volume of calculation for determining the coordinate positions of the center positions of respective cells compensated for image inclination by adding the inclination information of the two-dimensional matrix code. 3. The two-dimensional code reading method as defined in claim 2, herein coefficients in the image position calculating equations for calculating coordinate positions at four corners of the two-dimensional matrix code area are divided by a predetermined same cons ant to make integers and the coordinate positions of the cell center positions are determined by calculation with the integers only. 4. The two-dimensional code reading method as defined in claim 2, wherein a constant for dividing the coefficients symbolically determined for the image position calculating equations an selected from constants frequently and commonly used in the image position calculating equations is used to divide and convert the coefficients to smaller in size coefficients to make the two-dimensional matrix code readable. 5. The two-dimensional code reading method as defined in claim 1, herein coefficients in the image position calculating equations for calculating coordinate positions at four corners of the two-dimensional matrix code area are divided by a predetermined same constant to make them integers and the coordinate positions of the cell center positions are determined by calculation with the integers only. 6. The two-dimensional code reading method as defined in claim 1 wherein a constant for dividing the coefficients symbolical determined for the image position calculating equations an selected from constants frequently and commonly used in the image position calculating equations is used to divide and convert the coefficients to smaller in size coefficients to make the two-dimensional matrix code readable. 7. The two-dimensional code reading program which describes the two-dimensional code reading method defined in claim 1 by program codes executable by a computer. 8. A program recording medium which is readable by a computer and holding thereon the two-dimensional code reading program of claim 7. 9. A two-dimensional code reading method comprising processing steps of:acquiring an image of a stack type two-dimensional code composed of a number of bar codes arranged in multiple layers in a direction perpendicular to a direction of arrangement of bars in each bar code representing data;deciding a two-dime nsional code area in the image;setting an inspect on line identifying a center position of each of the bar codes, said inspection line joining one of two pairs of opposites of four sides representing a boundary of the decided two-dimensional code area, said pair opposite to each other in the direction of arrangement of bars in each bar code; andreproducing information of the two-dimensional code based on the inspection lines set in the inspection line setting step,wherein coefficient in image position calculating equations for calculating coordinate positions of center positions of respective cells in the two-dimensional code compensated for image inclination by adding inclination information for the two-dimensional code are calculated for setting the inspection lines on the two-dimensional cod image based on coordinate positions of four points within the two-dimensional code area decided by the two-dimensional code area decoding step. 10. The two-dimensional code reading program which describes the two-dimensional code reading method defined in claim 9 by program codes executable by a computer. 11. A program recording medium which is readable by a computer and holding thereon the two-dimensional code reading program of claim 10. 12. A two-dimensional code reading device comprising:an image capturing portion for capturing an image of a matrix type two-dimensional code composed of a number of cells arranged in vertical and horizontal directions to form a matrix of the cells each representing binary coded data,a two-dimensional code area deciding portion for deciding a two-dimensional code area in the two-dimensional code image,an inspection line setting portion for setting inspection lines identifying a center position of each of the cells, said inspection lines each joining two paired opposites of four sides defining a boundary of the decided two-dimensional code area and a decoding portion for reproducing information of the two-dimensional code based on the inspection lines,wherein the inspection line setting portion based on coordinate positions of four points within the two-dimensional code area decided by the two-dimensional code area deciding portion calculates coefficients for image position calculating equations for determining coordinate positions of center positions of respective cells in the two-dimensional code compensated for the inclination of the image by adding inclination information for the two-dimensional code. 13. The A two-dimensional code reading device as defined in claim 12, wherein each of the image position calculating equations to determining the coordinate positions of the center positions of he respective cells in the two-dimensional code image is expressed by a recurrence formula with respect to a center position of each of the cells to reduce a volume of calculations for determining the coordinate positions of the center positions of respective ells compensated for image inclination by adding the inclination of the two-dimensional code by adding inclination information for the two-dimensional code. 14. The two-dimensional code reading device as defined in claim 13, wherein coefficients in the image position calculating equations for calculating coordinate positions at four corners of the two-dimensional code area are divided by a predetermined same constant to make them integers and the coordinate positions of the cell center positions are determined by calculation with the integers only. 15. The two-dimensional code reading device as defined in claim 13, wherein a constant for dividing the coefficients symbolical determined for the image position calculating equations a selected from constants frequently and commonly used in the image position calculating equations is used to divide and convert the coefficients to smaller in size coefficients to make the two-dimensional code readable. 16. The two-dimensional code reading device as defined in claim 12, wherein coefficients in the image position ca lculating equations for calculating coordinate positions at four corners of the two-dimensional code area are divided by a predetermined same constant to make integers and the coordinate positions of the cell center positions are determined by calculation with the integers only. 17. The two-dimensional code reading device as defined in clam 12 , wherein a constant for dividing the coefficients symbolically determined for the image position calculating equations a selected from constants frequently and commonly used in the image position calculating equations is used to divide and convert the coefficients to smaller in size coefficients to make the two-dimensional code readable. 18. The digital camera incorporating a two-dimensional code reading device as defined in claim 12. 19. The portable telephone with a digital camera, which incorporates a two-dimensional code reading device as defined in claim 12.