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US6418244B2 Expired / Lapsed US ⏱️ 0.0 years remaining

Border-less clock free two-dimensional barcode and method for printing and reading the same

Assignee: Panasonic Holdings Corp
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Filing: 2001-01-23
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Granted: 2002-07-09
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Expires: 2021-01-23
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Abstract

Abstract Inventive two-dimensional barcodes, each having encoded digital information in a bitmap representing preferably randomized encoded data bits, are printed onto a printed medium. Preferably, error correction codes are added to the digital information to ensure that the decoding process accurately reproduce the digital information. In one embodiment, the bitmap may further include "anchor" bits in each corner, which are used as part of the skew estimation and deskewing processes during decoding. In a second embodiment, no "anchor" bits are required. The encoded digital information is mapped into the two-dimensional barcode in such a way as to minimize the errors caused by damage to particular rows and/or columns, for example, row damage caused by faxing the printed barcode. To extract the encoded digital information from the printed medium, the printed medium is scanned, then the bitmap is located within the printed medium. The skew of the bitmap, if any, is determined, and the bitmap is deskewed if necessary. The bitmap is then cropped, and the randomized digital information is read from the bitmap. The digital information is derandomized and any error correction codes are removed, in the process correcting and/or recording any errors discovered, thereby reproducing the original encoded digital information.

Inventors

  • 👤 Jiangying Zhou
  • 👤 Daniel P. Lopresti
  • 👤 Andrew Tomkins

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 20:20
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/10; G06K7/14; G06K19/00; G06K19/06; G06K19/06009; G06K19/06018; G06K19/06028; G06K19/06037

Claims Analysis

Total Claims: 24
Claim 1
Independent Claim 86 words
A method of encoding information for printing on a printed medium, comprising the steps of: converting said information into a data stream having a sequence of “0” and “1” characters representing data bits; randomizing said data stream to produce a randomized data stream having a sequence of “0” and “1” characters; formatting the randomized data stream into a two-dimensional bitmap of rows and columns including the randomized data stream bits and an anchor bit in one corner; and printing the formatted bitmap onto said printed medium.
Claim 2
Independent Claim 86 words
A method of encoding information for printing on a printed medium, comprising the steps of: converting said information into a data stream having a sequence of “0” and “1” characters representing data bits; randomizing said data stream to produce a randomized data stream having a sequence of “0” and “1” characters; formatting the randomized data stream into a two-dimensional bitmap of rows and columns including the randomized data stream bits and an anchor bit in one corner; and printing the formatted bitmap onto said printed medium.
Claim 3
Dependent Claim 25 words
The method as in claim 1 , wherein said formatting step includes the addition of an anchor bit into each corner of said two-dimensional bitmap.
Claim 4
Dependent Claim 55 words
The method as in claim 1 , wherein said formatting step includes the step of mapping the randomized data stream such that each data bit within each block in said data stream is separated from every other data bit within the same block by at least one row and one column in said two-dimensional bitmap.
Claim 5
Dependent Claim 39 words
The method as in claim 1 , wherein said randomizing step comprises the step of repeatedly randomizing said data stream by alternative designated keys until the randomized data stream contains a substantially uniform distribution of “0” and “1” characters.
Claim 6
Dependent Claim 15 words
The method as in claim 1 , further comprising the step of compressing said information.
Claim 7
Dependent Claim 22 words
The method as in claim 1 , further comprising the step of adding error correction code data bits to said data stream.
Claim 8
Dependent Claim 25 words
The method as in claim 1 , further comprising the step of duplicating said data stream to produce redundant data for improving reliability upon encoding.
Claim 9
Independent Claim 88 words
A method of encoding information for printing on a printed medium, comprising the steps of: converting said information into a data stream having a sequence of “0” and “1” characters representing data bits; randomizing said data stream to produce a randomized data stream having a sequence of “0” and “1” characters; formatting the randomized data stream into a two-dimensional bitmap of rows and columns including the randomized data stream bits and an anchor bit in at least one corner; and printing the formatted bitmap onto said printed medium.
Claim 10
Independent Claim 88 words
A method of encoding information for printing on a printed medium, comprising the steps of: converting said information into a data stream having a sequence of “0” and “1” characters representing data bits; randomizing said data stream to produce a randomized data stream having a sequence of “0” and “1” characters; formatting the randomized data stream into a two-dimensional bitmap of rows and columns including the randomized data stream bits and an anchor bit in at least one corner; and printing the formatted bitmap onto said printed medium.
Claim 11
Dependent Claim 25 words
The method as in claim 8 , wherein said formatting step includes the addition of an anchor bit into each corner of said two-dimensional bitmap.
Claim 12
Dependent Claim 55 words
The method as in claim 8 , wherein said formatting step includes the step of mapping the randomized data stream such that each data bit within each block in said data stream is separated from every other data bit within the same block by at least one row and one column in said two-dimensional bitmap.
Claim 13
Dependent Claim 39 words
The method as in claim 8 , wherein said randomizing step comprises the step of repeatedly randomizing said data stream by alternative designated keys until the randomized data stream contains a substantially uniform distribution of “0” and “1” characters.
Claim 14
Dependent Claim 15 words
The method as in claim 8 , further comprising the step of compressing said information.
Claim 15
Dependent Claim 21 words
The method as in claim 8 , further comprising the step of adding error correction code-data bits to said data stream.
Claim 16
Dependent Claim 25 words
The method as in claim 8 , further comprising the step of duplicating said data stream to produce redundant data for improving reliability upon encoding.
Claim 17
Independent Claim 119 words
A method of encoding information for printing on a printed medium, comprising the steps of: converting said information into a data stream having a sequence of “0” and “1” characters representing data bits; randomizing said data stream to produce a randomized data stream having a sequence of“0” and “1” characters; mapping the randomized data stream to a digital two-dimensional bitmap of rows and columns such that each data bit within each block in said data stream is separated from every other data bit within the same block by at least one row and one column; formatting said digital two-dimensional bitmap to produce a pixel based two-dimensional bitmap having data pixels; and printing the formatted bitmap onto said printed medium.
Claim 18
Independent Claim 119 words
A method of encoding information for printing on a printed medium, comprising the steps of: converting said information into a data stream having a sequence of “0” and “1” characters representing data bits; randomizing said data stream to produce a randomized data stream having a sequence of“0” and “1” characters; mapping the randomized data stream to a digital two-dimensional bitmap of rows and columns such that each data bit within each block in said data stream is separated from every other data bit within the same block by at least one row and one column; formatting said digital two-dimensional bitmap to produce a pixel based two-dimensional bitmap having data pixels; and printing the formatted bitmap onto said printed medium.
Claim 19
Dependent Claim 39 words
The method as in claim 15 , wherein said randomizing step comprises the step of repeatedly randomizing said data stream by alternative designated keys until the randomized data stream contains a substantially uniform distribution of “0” and “1” characters.
Claim 20
Dependent Claim 15 words
The method as in claim 15 , further comprising the step of compressing said information.
Claim 21
Dependent Claim 22 words
The method as in claim 15 , further comprising the step of adding error correction code data bits to said data stream.
Claim 22
Dependent Claim 25 words
The method as in claim 15 , further comprising the step of duplicating said data stream to produce redundant data for improving reliability upon encoding.
Claim 23
Independent Claim 79 words
A method of encoding information for printing on a printed medium, comprising the steps of: converting said information into a data stream having a sequence of “0” and “1” characters representing data bits; randomizing said data stream by alternate designated keys until the randomized data stream contains a uniform distribution of “0” and “1” characters; formatting said digital two-dimensional bitmap to produce a pixel based two-dimensional bitmap having data pixels; and printing the formatted bitmap onto said printed medium.
Claim 24
Independent Claim 79 words
A method of encoding information for printing on a printed medium, comprising the steps of: converting said information into a data stream having a sequence of “0” and “1” characters representing data bits; randomizing said data stream by alternate designated keys until the randomized data stream contains a uniform distribution of “0” and “1” characters; formatting said digital two-dimensional bitmap to produce a pixel based two-dimensional bitmap having data pixels; and printing the formatted bitmap onto said printed medium.

References Cited (Backward Citations)

US5640466A Cited
US5862260A Cited
US5862270A Cited
US5974199A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2005-07-08 2006-01-07 2006-07-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2009-07-08 2010-01-07 2010-07-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2013-07-08 2014-01-07 2014-07-09 $7700.00 Window Closed / Lapsed

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