Systems and methods for decoding two-dimensional matrix symbols with incomplete or absent fixed patterns
AssigneeCognex Corporation
InventorsXiangyun Ye, Xianju Wang, James A. Negro
Life of this patent
Estimating the term…
Abstract
Systems and methods for reading a two-dimensional matrix symbol or for determining if a two-dimensional matrix symbol is decodable are disclosed. The systems and methods can include a data reading algorithm that receives an image, locates at least a portion of the data modules within the image without using a fixed pattern, fits a model of the module positions from the image, extrapolates the model resulting in predicted module positions, determines module values from the image at the predicted module positions, and extracts a binary matrix from the module values.
Claims20
A system for reading a two-dimensional matrix symbol including data modules each having a module value and a module position, the two-dimensional matrix symbol encoding a data set, the system comprising:
- an imaging device, the imaging device configured to acquire an image containing at least a portion of the two-dimensional matrix symbol;
- a processor, the processor operatively coupled to the imaging device, the processor configured to execute a data reading algorithm, wherein the data reading algorithm receives the image, prioritizes one or more candidate regions based on an edge density of the one or more candidate regions, and extracts a binary matrix from the one or more candidate regions;
- and
- a binary matrix decoder operatively coupled to the processor, the binary matrix decoder configured to execute a decoding algorithm that decodes the binary matrix.
A method of reading a two-dimensional matrix symbol including data modules each having a module value and a module position, the two-dimensional matrix symbol encoding a data set, the method comprising:
- receiving an image at a processor, the image containing at least a portion of the two-dimensional matrix symbol;
- prioritizing one or more candidate regions based on an edge density of the one or more candidate regions;
- extracting, using the processor, a binary matrix from the one or more candidate regions;
- and
- decoding the binary matrix.
A system for determining if a two-dimensional matrix symbol is decodable, the two-dimensional matrix symbol including data modules each having a module value and a module position, the system comprising:
- an imaging device, the imaging device configured to acquire an image containing the two-dimensional matrix symbol;
- a processor, the processor operatively coupled to the imaging device, the processor configured to execute a data reading algorithm, wherein the data reading algorithm receives the image, prioritizes one or more candidate regions based on edge density of the one or more candidate regions, and extracts a binary matrix from the one or more candidate regions,
- wherein the data reading algorithm includes a frequency-domain analysis.
Dependencies are inferred from the claim text.