METHOD OF ENCODING CODING PATTERN TO MINIMIZE CLUSTERING OF MACRODOTS

• US 20110181916A1
• Filed: 01/27/2010
• Published: 07/28/2011
• Est. Priority Date: 01/27/2010
• Status: Abandoned Application

• Current Assignee: Silverbrook Research Pty Limited
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Napper, Jonathon Leigh, Lapstun, Paul
• Application Number:
  US12/694,267
• Publication Number:
  US 20110181916A1
• Time in Patent Office: Days
• US Class Current: 358/1.18
• CPC Class Codes: G06K 19/06037 multi-dimensional coding

Abstract

A method of encoding a coding pattern for disposition on or in a substrate. The method comprises the step of encoding contiguous data symbols for the coding pattern. Each data symbol is represented by d macrodots on the surface, each of the d macrodots occupying a respective position from a plurality of predetermined possible positions p, the respective positions of the d macrodots representing one of i possible data values. The encoding step selects a predetermined number of unused symbol values in each data symbol in order to minimize clustering of macrodots between adjacent data symbols.

Claims

1. A method of encoding a coding pattern for disposition on or in a substrate, said method comprising the step of:

encoding contiguous data symbols for said coding pattern, each data symbol being represented by d macrodots on said surface, each of said d macrodots occupying a respective position from a plurality of predetermined possible positions p, the respective positions of said d macrodots representing one of i possible data values,

wherein said encoding selects a predetermined number of unused symbol values in each data symbol in order to minimize clustering of macrodots between adjacent data symbols.

2. The method of claim 1, wherein each data symbol is a j-bit data symbol, and wherein said encoding selects (ĩ

2^j) unused symbol values in each data symbol in order to minimize clustering of macrodots between adjacent data symbols.

3. The method of claim 1, wherein said encoding minimizes an overall visibility of said coding pattern disposed on said surface.

4. The method of claim 1, further comprising the step of printing said contiguous data symbols onto said surface.

5. The method of claim 1, wherein said unused symbol values represent symbol values having d macrodots clustered together in a predetermined region of said data symbol.

6. The method of claim 5, wherein said predetermined region of said data symbol is selected from at least one of:

an edge region; and

a corner region.

7. The method of claim 1, wherein said unused symbol values are treated as erasures.

8. The method of claim 1, wherein p≧

2 m.

9. The method of claim 1, wherein d is an integer value of 2, 3, 4, 5 or 6.

10. The method of claim 1, wherein p is an integer value of 4, 5, 6, 7, 8, 9, 10, 11 or 12.

11. The method of claim 1, wherein p=7 and the data symbol is substantially L-shaped having corner regions, a convex edge and a concave edge.

12. The method of claim 11, wherein d=3 which provides 35 possible symbol values for a 5-bit data symbol, and wherein 3 unused symbol values represent symbol values having macrodot triplets clustered together in the corner regions of said data symbol.

13. The method of claim 11, wherein d=2 which provides 21 possible symbol values for a 4-bit data symbol, and wherein 5 unused symbol values represent symbol values having macrodot doublets clustered together along the convex edge of said data symbol.

14. The method of claim 1, wherein said coding pattern further comprises a plurality of target elements defining a target grid, said targets elements being distinguishable from said macrodots.

15. The method of claim 14, wherein said coding pattern comprises a plurality of symbol groups, each symbol group comprising at least one target element and a plurality of said data symbols.

16. The method of claim 15, wherein said coding pattern comprises a plurality of tags, each tag comprising a plurality of symbol groups and a plurality of target elements.

17. The method of claim 16, wherein each tag comprises at least one Reed-Solomon codeword comprised of a plurality of said data symbols.

18. The method of claim 17, wherein each tag comprises at least one local codeword identifying a location of a respective tag.

19. The method of claim 17, wherein each tag comprises one or more common codewords, each common codeword being common to a plurality of contiguous tags.

20. The method of claim 1, wherein said plurality of macrodots further encode registration symbols identifying one or more of:

an integer value of d;

a translation of a symbol group relative to a tag containing said symbol group, each symbol group containing a plurality of said data symbols;

an orientation of a layout of said data symbols with respect to a target grid; and

a flag.