Bar code reader for accurately reading two-dimensional bar code images
First Claim
1. A bar code reader comprising:
- an imaging element for recording a two-dimensional bar code;
frame memory means for storing a two-dimensional bar code image recorded by means of the imaging element; and
bar code reading-control means for finding coordinates of four corners of the two-dimensional bar code image stored in the frame memory means, for finding equations of four straight lines passing through four sides of the two-dimensional bar code image, said four straight lines passing through respective corners of the two-dimensional bar code image stored in the frame memory means, for setting a plurality of scan lines at equal intervals between those two of the four straight lines which cross two portions corresponding to start and end codes of the two-dimensional bar code image, and further setting a plurality of sampling lines at equal intervals between remaining two straight lines extending along said two portions, respectively, and for sampling the two-dimensional bar code image at positions corresponding to intersections between the scan lines and the sampling lines, whereby bar code information is read out from the two-dimensional bar code image.
1 Assignment
0 Petitions
Accused Products
Abstract
A bar code reader includes an imaging element for recording a two-dimensional bar code, a frame memory for storing a two-dimensional bar code image recorded by the imaging element, and a bar code reading-control unit which finds coordinates of four corners of the two-dimensional bar code image stored in the frame memory, finds equations of four straight lines passing through four sides of the two-dimensional bar code image, sets a plurality of scan lines at equal intervals between those two of the four straight lines which cross two portions corresponding to start and end codes of the two-dimensional bar code image, and further sets a plurality of sampling lines at equal intervals between remaining two straight lines extending along the two portions, respectively, and samples the two-dimensional bar code image at positions corresponding to intersections between the scan lines and the sampling lines, whereby bar code information is read out from the two-dimensional bar code image.
-
Citations
3 Claims
-
1. A bar code reader comprising:
-
an imaging element for recording a two-dimensional bar code; frame memory means for storing a two-dimensional bar code image recorded by means of the imaging element; and bar code reading-control means for finding coordinates of four corners of the two-dimensional bar code image stored in the frame memory means, for finding equations of four straight lines passing through four sides of the two-dimensional bar code image, said four straight lines passing through respective corners of the two-dimensional bar code image stored in the frame memory means, for setting a plurality of scan lines at equal intervals between those two of the four straight lines which cross two portions corresponding to start and end codes of the two-dimensional bar code image, and further setting a plurality of sampling lines at equal intervals between remaining two straight lines extending along said two portions, respectively, and for sampling the two-dimensional bar code image at positions corresponding to intersections between the scan lines and the sampling lines, whereby bar code information is read out from the two-dimensional bar code image. - View Dependent Claims (2, 3)
-
Specification