Embedded interaction code recognition

A computer-readable storage medium containing instructions for executing a method for identifying a location of an embedded interaction code (EIC) symbol on a surface, the method comprising:

• capturing an image of the surface containing a portion of an EIC symbol array having a plurality of grid cells formed by a plurality of grid lines, each grid line having a plurality of data dot positions and orientation dot positions;
• for each of a plurality of grid cells within the captured image,
• determining a graylevel for each of a plurality of data dot positions located on each grid line portion associated with the grid cell, and
• determining positions of black data dots by comparing the determined graylevels of the data dot positions;
• for each of a plurality of orientations of the grid cells, determining the number of black data dots at orientation dot positions;
• determining a correct orientation for the EIC symbol array and which grid cells correspond to EIC symbols based on which rotated position of the grid cells contains the fewest number of black dots at orientation dot positions;
• orienting the EIC symbol array based on the determined correct orientation for the EIC symbol array;
• identifying an EIC symbol in the EIC pattern with the corrected orientation, the EIC symbol having an associated grid cell;
• extracting bits from at least one edge of the grid cell associated with the identified EIC symbol based on the position of a black data dot on the at least one edge;
• and
• determining the position of the identified EIC symbol relative to the surface based at least in part on the extracted bits.

A system for identifying a location of an embedded interaction code (EIC) symbol on a surface, the system comprising:

• a component that captures an image of the surface containing a portion of an EIC symbol array having a plurality of grid cells formed by a plurality of grid lines, each grid line having a plurality of data dot positions and orientation dot positions;
• a component that, for each of a plurality of grid cells within the captured image,
• determines a graylevel for each of a plurality of data dot positions located on each grid line portion associated with the grid cell, and
• determines positions of black data dots by comparing the determined graylevels of the data dot positions;
• a component that, for each of a plurality of orientations of the grid cells, determines the number of black data dots at orientation dot positions;
• a component that determines a correct orientation for the EIC symbol array and which grid cells correspond to EIC symbols based on which rotated position of the grid cells contains the fewest number of black dots at orientation dot positions;
• a component that orients the EIC symbol array based on the determined correct orientation for the EIC symbol array;
• a component that identifies an EIC symbol in the EIC pattern with the corrected orientation, the EIC symbol having an associated grid cell;
• a component that extracts bits from at least one edge of the grid cell associated with the identified EIC symbol based on the position of a black data dot on the at least one edge;
• and
• a component that determines the position of the identified EIC symbol relative to the surface based at least in part on the extracted bits.