CA2463324A1 - Method of compressing digital ink - Google Patents

Method of compressing digital ink Download PDF

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Publication number
CA2463324A1
CA2463324A1 CA002463324A CA2463324A CA2463324A1 CA 2463324 A1 CA2463324 A1 CA 2463324A1 CA 002463324 A CA002463324 A CA 002463324A CA 2463324 A CA2463324 A CA 2463324A CA 2463324 A1 CA2463324 A1 CA 2463324A1
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CA
Canada
Prior art keywords
ordinates
ordinate
digital ink
alpha
stroke
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA002463324A
Other languages
French (fr)
Other versions
CA2463324C (en
Inventor
Jonathon Leigh Napper
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Silverbrook Research Pty Ltd
Original Assignee
Silverbrook Research Pty Ltd.
Jonathon Leigh Napper
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Silverbrook Research Pty Ltd., Jonathon Leigh Napper filed Critical Silverbrook Research Pty Ltd.
Publication of CA2463324A1 publication Critical patent/CA2463324A1/en
Application granted granted Critical
Publication of CA2463324C publication Critical patent/CA2463324C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F18/00—Pattern recognition
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
    • H03M7/00—Conversion of a code where information is represented by a given sequence or number of digits to a code where the same, similar or subset of information is represented by a different sequence or number of digits
    • H03M7/30—Compression; Expansion; Suppression of unnecessary data, e.g. redundancy reduction
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V30/00—Character recognition; Recognising digital ink; Document-oriented image-based pattern recognition
    • G06V30/10—Character recognition
    • G06V30/14—Image acquisition
    • G06V30/142—Image acquisition using hand-held instruments; Constructional details of the instruments
    • G06V30/1423—Image acquisition using hand-held instruments; Constructional details of the instruments the instrument generating sequences of position coordinates corresponding to handwriting
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
    • H03M7/00—Conversion of a code where information is represented by a given sequence or number of digits to a code where the same, similar or subset of information is represented by a different sequence or number of digits
    • H03M7/30—Compression; Expansion; Suppression of unnecessary data, e.g. redundancy reduction
    • H03M7/40—Conversion to or from variable length codes, e.g. Shannon-Fano code, Huffman code, Morse code

Abstract

A method of compressing a digital ink input is disclosed. The digital ink includes a sequence of strokes, each stroke being represented as a series of digital words representing x and y co-ordinates, the compressed digital ink data including, for each stroke, at least one reference co-ordinate expressed in absolute terms, with subsequent co-ordinates being expressed in terms of an offset from a co-ordinate, estimated using linear prediction, such that a given co-ordinate may be determined on the basis of the previous m co-ordinates as formula (I); where ci are coefficients dependent on the nature of the digital ink, and .alpha. represents either an x or a y co-ordinate.

Claims (11)

1. A method of compressing a digital ink input including a sequence of strokes, each stroke being represented as a series of digital words representing x and y co-ordinates, the compressed digital ink data including, for each stroke, at least one reference co-ordinate expressed in absolute terms, with subsequent co-ordinates being expressed in terms of an offset from a co-ordinate, estimated using linear prediction, such that a given co-ordinate may be estimated on the basis of the previous m co-ordinates as:
where c i are coefficients selected to model characteristics of the digital ink, and .alpha.
represents either an x or a y co-ordinate.
2. A method as claimed in claim 1 wherein m is 2, and a given co-ordinate may be defined:
.alpha.n = C1.alpha.n-1 + C2a.alpha.n-2
3. A method as claimed in claim 2 wherein C1 > 0 and C2 < 0.
4. A method as claimed in claim 3 wherein:
1 <= C1 <= 3 and -2 <= C2 <= 1
5. A method as claimed in claim 4 wherein C1 = 2 and C2 = -1.
6. A method as claimed in any one of claims 1 to 4 wherein the coefficient values (C i) for x co-ordinates are different to the coefficients for y co-ordinates.
7. A method as claimed in claim 6 wherein for x co-ordinates:
C1 = 1.857 C2 = -0.856, and for y co-ordinates:
C1 = 1.912 C2 = -0.913
8. A method as claimed in claim 1 wherein m is 3, and a given co-ordinate may be defined:
~n = C1.alpha.n-1 + C2.alpha.n-2 + C3.alpha.n-3
9. A method as claimed in claim 8 wherein C1 > 0 and C2 < 0 and C3 < 1.
10. A method as claimed in claim 8 or 9 wherein the coefficient values (C1) for x co-ordinates are different to the coefficients for y co-ordinates.
11. A method as claimed in claim 10 wherein for x co-ordinates:
for y co-ordinates:
C1 = 1.799 C2 = -0.722 C3 = -0.078, and for y co-ordinates:
C1 = 2.009 C2 = -1.107 C3 = -0.098
CA2463324A 2001-11-16 2002-10-15 Method of compressing digital ink Expired - Fee Related CA2463324C (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
AUPR8902 2001-11-16
AUPR8902A AUPR890201A0 (en) 2001-11-16 2001-11-16 Methods and systems (npw005)
PCT/AU2002/001391 WO2003044723A1 (en) 2001-11-16 2002-10-15 Method of compressing digital ink

Publications (2)

Publication Number Publication Date
CA2463324A1 true CA2463324A1 (en) 2003-05-30
CA2463324C CA2463324C (en) 2011-01-18

Family

ID=3832719

Family Applications (1)

Application Number Title Priority Date Filing Date
CA2463324A Expired - Fee Related CA2463324C (en) 2001-11-16 2002-10-15 Method of compressing digital ink

Country Status (10)

Country Link
US (5) US7308148B2 (en)
EP (1) EP1444641A4 (en)
JP (1) JP2005509385A (en)
KR (1) KR100612759B1 (en)
CN (1) CN1287320C (en)
AU (1) AUPR890201A0 (en)
CA (1) CA2463324C (en)
IL (1) IL161749A0 (en)
WO (1) WO2003044723A1 (en)
ZA (1) ZA200402927B (en)

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AUPR890201A0 (en) 2001-11-16 2001-12-06 Silverbrook Research Pty. Ltd. Methods and systems (npw005)
US7474770B2 (en) * 2005-06-28 2009-01-06 Beigi Homayoon S M Method and apparatus for aggressive compression, storage and verification of the dynamics of handwritten signature signals
JP4869149B2 (en) * 2007-05-16 2012-02-08 オリンパスイメージング株式会社 Image data compression apparatus, image data compression method and program
US8644171B2 (en) * 2007-08-09 2014-02-04 The Boeing Company Method and computer program product for compressing time-multiplexed data and for estimating a frame structure of time-multiplexed data
CN102299718A (en) * 2010-06-25 2011-12-28 汉王科技股份有限公司 Compression and decompression methods for locus at hand-written terminal
GB2483282B (en) * 2010-09-03 2017-09-13 Advanced Risc Mach Ltd Data compression and decompression using relative and absolute delta values
TWI486837B (en) * 2012-09-18 2015-06-01 Egalax Empia Technology Inc Prediction-based touch contact tracking
GB2511355B (en) * 2013-03-01 2015-06-03 Gurulogic Microsystems Oy Encoder, decoder and method
US9535646B2 (en) 2013-06-18 2017-01-03 Microsoft Technology Licensing, Llc Methods and systems for electronic ink projection
US9235748B2 (en) * 2013-11-14 2016-01-12 Wacom Co., Ltd. Dynamic handwriting verification and handwriting-based user authentication
EP3061067B1 (en) * 2013-10-25 2023-11-29 Wacom Co., Ltd. Dynamic handwriting verification, handwriting-baseduser authentication, handwriting data generation, and handwriting data preservation
US10032065B2 (en) 2013-10-25 2018-07-24 Wacom Co., Ltd. Dynamic handwriting verification, handwriting-based user authentication, handwriting data generation, and handwriting data preservation
EP3107300A1 (en) * 2015-06-15 2016-12-21 Thomson Licensing Method and device for encoding both a high-dynamic range frame and an imposed low-dynamic range frame
US10338807B2 (en) 2016-02-23 2019-07-02 Microsoft Technology Licensing, Llc Adaptive ink prediction
CN112040562B (en) * 2020-08-03 2022-04-29 华中科技大学 Communication method of intelligent pen terminal, intelligent pen terminal and communication system

Family Cites Families (38)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5856913B2 (en) 1980-10-28 1983-12-17 日本電信電話株式会社 Handwritten signal encoding method
US4509150A (en) * 1980-12-31 1985-04-02 Mobil Oil Corporation Linear prediction coding for compressing of seismic data
US4542412A (en) * 1982-02-04 1985-09-17 Shaken Co., Ltd. Method for compressing character or pictorial image data
US4781096A (en) * 1984-10-09 1988-11-01 Nippon Gakki Seizo Kabushiki Kaisha Musical tone generating apparatus
US4864618A (en) * 1986-11-26 1989-09-05 Wright Technologies, L.P. Automated transaction system with modular printhead having print authentication feature
US5051736A (en) * 1989-06-28 1991-09-24 International Business Machines Corporation Optical stylus and passive digitizing tablet data input system
US5245679A (en) * 1990-05-11 1993-09-14 Hewlett-Packard Company Data field image compression
WO1991018479A1 (en) * 1990-05-14 1991-11-28 Eastman Kodak Company Block adaptive linear predictive coding with adaptive gain and bias
US5852434A (en) * 1992-04-03 1998-12-22 Sekendur; Oral F. Absolute optical position determination
US5477012A (en) * 1992-04-03 1995-12-19 Sekendur; Oral F. Optical position determination
WO1994003853A1 (en) * 1992-07-29 1994-02-17 Communication Intelligence Corporation A method and apparatus for compression of electronic ink
WO1994004992A1 (en) * 1992-08-20 1994-03-03 Communication Intelligence Corporation A method for dynamic reconstruction of handwritten data
DE69425412T2 (en) * 1993-11-23 2001-03-08 Ibm System and method for automatic handwriting recognition using a user-independent chirographic label alphabet
US5687254A (en) 1994-06-06 1997-11-11 Xerox Corporation Searching and Matching unrecognized handwriting
US6101280A (en) * 1994-07-04 2000-08-08 Hewlett-Packard Company Method and apparatus for compression of electronic ink
EP0691623B1 (en) 1994-07-04 2001-10-04 Hewlett-Packard Company, A Delaware Corporation Scribble matching
US5652412A (en) * 1994-07-11 1997-07-29 Sia Technology Corp. Pen and paper information recording system
US5661506A (en) * 1994-11-10 1997-08-26 Sia Technology Corporation Pen and paper information recording system using an imaging pen
US5528003A (en) * 1994-12-14 1996-06-18 International Business Machines Corporation Data compression for pen stroke input
US6125207A (en) * 1995-06-05 2000-09-26 Motorola, Inc. Encoded facsimile communication with a selective system and method therefor
US6278445B1 (en) * 1995-08-31 2001-08-21 Canon Kabushiki Kaisha Coordinate input device and method having first and second sampling devices which sample input data at staggered intervals
US6081261A (en) 1995-11-01 2000-06-27 Ricoh Corporation Manual entry interactive paper and electronic document handling and processing system
US6295378B1 (en) * 1996-02-29 2001-09-25 Sanyo Electric Co., Ltd. Handwriting stroke information encoder which encodes handwriting stroke information by sampling
US5692073A (en) * 1996-05-03 1997-11-25 Xerox Corporation Formless forms and paper web using a reference-based mark extraction technique
JPH1011208A (en) * 1996-06-24 1998-01-16 Sharp Corp Coordinate input device
GB9625661D0 (en) * 1996-12-11 1997-01-29 Hewlett Packard Co A method and apparatus for compression of electronic ink
US6518950B1 (en) 1997-10-07 2003-02-11 Interval Research Corporation Methods and systems for providing human/computer interfaces
JP2882404B1 (en) * 1997-12-17 1999-04-12 日本電気株式会社 Handwritten code processing device
WO1999050751A1 (en) 1998-04-01 1999-10-07 Xerox Corporation Routing document identifiers
US6333966B1 (en) * 1998-08-18 2001-12-25 Neil Charles Schoen Laser accelerator femtosecond X-ray source
US6964374B1 (en) * 1998-10-02 2005-11-15 Lucent Technologies Inc. Retrieval and manipulation of electronically stored information via pointers embedded in the associated printed material
US6549675B2 (en) * 2000-12-20 2003-04-15 Motorola, Inc. Compression of digital ink
AUPR890201A0 (en) 2001-11-16 2001-12-06 Silverbrook Research Pty. Ltd. Methods and systems (npw005)
US7162087B2 (en) * 2001-12-28 2007-01-09 Anoto Ab Method and apparatus for recording of electronic handwriting
US20030123745A1 (en) * 2001-12-28 2003-07-03 Mattias Bryborn Method and apparatus for compression and reconstruction of electronic handwriting
US7312898B2 (en) * 2002-10-31 2007-12-25 Hewlett-Packard Development Company, L.P. Transformation of an input image to produce an output image
US7302106B2 (en) * 2003-05-19 2007-11-27 Microsoft Corp. System and method for ink or handwriting compression
US20050089237A1 (en) * 2003-10-24 2005-04-28 Jaehwa Park Method and apparatus for bezier curve approximation data compression

Also Published As

Publication number Publication date
US8345997B2 (en) 2013-01-01
EP1444641A1 (en) 2004-08-11
US7463779B2 (en) 2008-12-09
ZA200402927B (en) 2005-04-26
KR100612759B1 (en) 2006-08-21
US8121426B2 (en) 2012-02-21
US7308148B2 (en) 2007-12-11
CN1585956A (en) 2005-02-23
CN1287320C (en) 2006-11-29
JP2005509385A (en) 2005-04-07
US20090046936A1 (en) 2009-02-19
CA2463324C (en) 2011-01-18
US20040247191A1 (en) 2004-12-09
US20080056595A1 (en) 2008-03-06
IL161749A0 (en) 2005-11-20
US20120141040A1 (en) 2012-06-07
WO2003044723A1 (en) 2003-05-30
AUPR890201A0 (en) 2001-12-06
KR20050036894A (en) 2005-04-20
US20110007978A1 (en) 2011-01-13
EP1444641A4 (en) 2006-03-22
US7650033B2 (en) 2010-01-19

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