WO2000011834A1 - Signatures graphiques numeriques - Google Patents

Signatures graphiques numeriques Download PDF

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Publication number
WO2000011834A1
WO2000011834A1 PCT/US1998/017605 US9817605W WO0011834A1 WO 2000011834 A1 WO2000011834 A1 WO 2000011834A1 US 9817605 W US9817605 W US 9817605W WO 0011834 A1 WO0011834 A1 WO 0011834A1
Authority
WO
WIPO (PCT)
Prior art keywords
digital signature
digital
attachment
recipient
signature
Prior art date
Application number
PCT/US1998/017605
Other languages
English (en)
Inventor
Mary J. Cronin
Scott B. Guthery
Original Assignee
Schlumberger Industries, S.A.
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 Schlumberger Industries, S.A. filed Critical Schlumberger Industries, S.A.
Priority to PCT/US1998/017605 priority Critical patent/WO2000011834A1/fr
Priority to AU92943/98A priority patent/AU9294398A/en
Publication of WO2000011834A1 publication Critical patent/WO2000011834A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
    • H04N1/00127—Connection or combination of a still picture apparatus with another apparatus, e.g. for storage, processing or transmission of still picture signals or of information associated with a still picture
    • H04N1/00281—Connection or combination of a still picture apparatus with another apparatus, e.g. for storage, processing or transmission of still picture signals or of information associated with a still picture with a telecommunication apparatus, e.g. a switched network of teleprinters for the distribution of text-based information, a selective call terminal
    • H04N1/00312—Connection or combination of a still picture apparatus with another apparatus, e.g. for storage, processing or transmission of still picture signals or of information associated with a still picture with a telecommunication apparatus, e.g. a switched network of teleprinters for the distribution of text-based information, a selective call terminal with a digital transmission apparatus, e.g. a switched network of teleprinters for the distribution of text-based information, SMS or ISDN device
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T1/00—General purpose image data processing
    • G06T1/0021—Image watermarking
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/32—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
    • H04L9/3247—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials involving digital signatures
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
    • H04N1/00127—Connection or combination of a still picture apparatus with another apparatus, e.g. for storage, processing or transmission of still picture signals or of information associated with a still picture
    • H04N1/00281—Connection or combination of a still picture apparatus with another apparatus, e.g. for storage, processing or transmission of still picture signals or of information associated with a still picture with a telecommunication apparatus, e.g. a switched network of teleprinters for the distribution of text-based information, a selective call terminal
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
    • H04N1/32—Circuits or arrangements for control or supervision between transmitter and receiver or between image input and image output device, e.g. between a still-image camera and its memory or between a still-image camera and a printer device
    • H04N1/32101—Display, printing, storage or transmission of additional information, e.g. ID code, date and time or title
    • H04N1/32144—Display, printing, storage or transmission of additional information, e.g. ID code, date and time or title embedded in the image data, i.e. enclosed or integrated in the image, e.g. watermark, super-imposed logo or stamp
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N2201/00—Indexing scheme relating to scanning, transmission or reproduction of documents or the like, and to details thereof
    • H04N2201/32—Circuits or arrangements for control or supervision between transmitter and receiver or between image input and image output device, e.g. between a still-image camera and its memory or between a still-image camera and a printer device
    • H04N2201/3201—Display, printing, storage or transmission of additional information, e.g. ID code, date and time or title
    • H04N2201/3225—Display, printing, storage or transmission of additional information, e.g. ID code, date and time or title of data relating to an image, a page or a document
    • H04N2201/3233—Display, printing, storage or transmission of additional information, e.g. ID code, date and time or title of data relating to an image, a page or a document of authentication information, e.g. digital signature, watermark
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N2201/00—Indexing scheme relating to scanning, transmission or reproduction of documents or the like, and to details thereof
    • H04N2201/32—Circuits or arrangements for control or supervision between transmitter and receiver or between image input and image output device, e.g. between a still-image camera and its memory or between a still-image camera and a printer device
    • H04N2201/3201—Display, printing, storage or transmission of additional information, e.g. ID code, date and time or title
    • H04N2201/328—Processing of the additional information

Definitions

  • a digital signature is a digital representation of information identifying the author or source of a document which includes but is not limited to a demonstration of knowledge of secret or little-known information
  • a sender using a computer or similar digital means, composes a message he intends to send to one or more recipients.
  • a digital signature is derived based on some aspect of the message. How the digital signatures are actually coded and decoded are beyond the scope of this patent, but see Mitchell, Piper and Wild, "Digital Signatures", Contemporary Cryptology, pp. 325-378, which is incorporated herein by reference .
  • Digital signatures are typically attached to digital messages which are passed from one computer to another via a network - from small, in-house intranets to the large networks such as the Internet.
  • Current methods represent digital signatures as large blocks of alphanumeric, hexadecimal or binary characters.
  • a digital signature might be represented in an electronic mail (e- mail) as follows:
  • the present invention provides means for steganographically embedding a digital signature into a more intuitive signature graphic such as is shown at 50 in Fig. 1 or into an audio recording of the sender saying something such as "This document about widget pricing dated May 23, 1997, has been written by me.”
  • a method of digital communication comprises the steps of providing a digital message that the sender desires to send to one or more recipients; providing a digital signature such as a private key encrypted hash of the message or a biometric such as a private encryption key or unique biometric information such as a facial picture, a fingerprint, an iris or retinal scan, typing and handwriting patterns, hand or finger geometry or a voice print; providing a user- perceptible attachment such as a picture or audio,- embedding the digital signature into the attachment; attaching the attachment to the message to form a digital communication; and sending the communication.
  • a digital signature such as a private key encrypted hash of the message or a biometric such as a private encryption key or unique biometric information such as a facial picture, a fingerprint, an iris or retinal scan, typing and handwriting patterns, hand or finger geometry or a voice print
  • providing a user- perceptible attachment such as a picture or audio,- embedding the digital signature into the attachment
  • the digital signature is embedded into the attachment by substituting bits of the digital signature into selected least significant bits of the attachment. In this manner, the changes to the attachment are virtually undetectable by the recipient . The existence or the state of the attachment itself may alert the recipient to the fact that a digital signature is present.
  • a header may be embedded into the attachment at predetermined locations . This header may serve to identify the existence of the digital signature, or .the header may contain parameters which provide further information about the digital signature, e.g., coding technique, location within the attachment, etc.
  • the attachment may be modified before embedding the digital signature by any number and manner of transformations. Such modification may be used to alert the recipient that a digital signature is present. Examples of such modification transformations are warping and morphing .
  • Either the recipient can initiate verification of the digital signature, or such verification can come about automatically.
  • both the message and the attachment are available to the recipient.
  • the recipient may begin the verification process, for example, by selecting the attachment using a computer mouse.
  • Verification comprises extracting the digital signature from the attachment and verifying the validity of the digital signature according to standard digital signature techniques.
  • the recipient may be notified as to whether the digital signature is valid or not, or the digital signature may be displayed to the recipient.
  • the software that forms those functions may, for example, be incorporated in otherwise conventional e- mail software.
  • Fig. 1 illustrates a graphic signature as it might appear in an e-mail.
  • Fig. 2A illustrates a prior art electronic e-mail communication with an alphanumeric representation of a digital signature.
  • Fig. 2B illustrates an electronic e-mail communication with a graphic in which a digital signature is steganographically embedded.
  • Fig. 3 is a flowchart showing generally the process of embedding a digital signature.
  • Fig. 4 is a flowchart showing generally the process of extracting a digital signature and further processing it.
  • Fig. 5 illustrates a graphic which could be used to notify a recipient of a valid digital signature.
  • Fig. 2A illustrates an electronic mail (e-mail) communication 100 as it might appear in prior art.
  • the sender has composed a message 102, in this example, consisting of the sentence "Please give Alice Gilbert a master key," followed by a salutation.
  • a digital signature 104 is generated.
  • the digital signature may be based on the message 102 and a key known or provided to the sender' s computer, or it may be independent of the message 102 itself, as in the case where the signature is a fingerprint.
  • the digital signature 104 is appended to the message 102, along with some additional information 106, to form the digital communication, which is transmitted or sent to one or more intended recipients.
  • a non-technical person receiving this message may not immediately know the purpose of the digital signature 104 and/or how to use it.
  • Fig. 2B illustrates the equivalent email communication 110 as produced by the present invention.
  • a message 112 consists of some text the sender wishes to convey to the recipient, again, in this example, the sentence "Please give Alice Gilbert a master key," followed by a salutation.
  • a graphic, digitized (not digital) signature 114 of the sender (Sally) is attached to the communication. This graphic 114 has been slightly altered such that it contains the same digital signature as shown in 104 of Fig. 2A.
  • the recipient When the signed email 110 of Fig. 2B arrives at its destination and is selected for reading by the recipient, the recipient is offered the opportunity to verify the signature. If the user decides to verify the signature, for example by selecting a "Verify" button, then the e-mail software extracts the digital signature 104 from the graphic 114 and performs the usual digital signature verification. If the digital signature 114 is verified, i.e., the digital signature supports the claim that the email comes from Sally Green, the software might display an acknowledgment such as "Signature verified as the signature of Sally Green," or a graphic 60 such as that shown in Fig. 5.
  • the message may be text, audio, graphic, or some other mode of conveying information digitally.
  • the communication is not limited to email.
  • the communication could be a transmittal of a World Wide Web page or some other means of digitally transmitting a message.
  • the attachment into which the digital signature is embedded may itself be text, audio, graphic, video, etc.
  • the attachment may be modified before embedding the digital signature. For example, warping and morphing, as well as other transformations, may be applied to a graphic or picture. Similarly, other types of transformations may be applied to audio signals. Such modifications may be used to alert the recipient that a digital signature is present .
  • Fig. 3 is a flowchart showing generally the process of embedding a digital signature.
  • the sender composes or otherwise provides a message comprising the information he wishes to communicate to the recipients .
  • an image or audio attachment is provided, and at 204 a digital signature is calculated or otherwise provided.
  • suitable digital signature algorithms can be found in "Digital Signature Schemes" by Birgit Pfitzmann and published by Springer-Verlag in 1996 (ISBN 3-540-61517- 2) which is herein incorporated by reference.
  • the attachment can be modified using image processing or audio processing algorithms .
  • the purpose of this transformation is to provide to the recipient an indicator that a digital signature has been included and can be validated.
  • an image may undergo warping 206, morphing 208, and/or other transformations 210.
  • Audio be may subjected to audio-type transforms, for example, filtering .
  • Warping 206 is typically applied to line-drawing images and comprises bending or moving some of the lines in the image. For example, if the original attachment is an image of a dragonfly and the body of the dragonfly is a long, curved cigar shape, this image can be warped by increasing or decreasing the bending of the body of the dragonfly.
  • the amount of warping is determined based on parameters computed from the document such as a word count .
  • Morphing algorithms 208 transform one image to another by computing a series of images visually between a beginning image and an ending image.
  • a user chooses an ending image to morph an original "signing" image toward. If some computed value for the message, such as a word count or a digital signature, is n on a scale from 0 to N, then the image that is n/N of the way from the original signing image to the ending image is selected as the attachment in which the digital signature will be embedded. Examples of suitable warping and morphing algorithms can be found in "Digital Image Warping" by George Wolberg and published by the IEEE Computer Society Press in 1990 (ISBN 0-81868944-7) which is herein incorporated by reference.
  • the digital signature is embedded into the attachment using steganographic techniques 212, described below.
  • the attachment is attached 214 to the message to form a communication, and finally, the communication is transmitted 216 to the intended recipients.
  • Steganographic algorithms are typically used to hide information in images, although the technique is easily applied to digital audio signals as well. What appears to be an innocent picture actually contains a secret message.
  • the embedding of the text into the picture is deliberately constructed so as to not disturb the image such that a viewer cannot tell that the picture contains a message simply by looking at it. In other words, the embedding does not alter - at least to the human eye or ear - the appearance of the picture or the sound of an audio.
  • each point (pixel) in the photograph is represented as a 16 -bit number where 0 represents all white, 32,768 represents all black and numbers in between represent shades of gray between white and black.
  • the digital signature can be embedded into the photograph by setting the low-order bit of a pixel (a point in the photograph) of the photograph to 0 when the corresponding bit in the digital signature is 0, and to 1 when the corresponding bit in the digital signature is 1. If the low-order bit in the pixel were originally 0 and it is now set to 1, then the pixel becomes just a little darker, but not enough to be noticeable.
  • Fig. 4 is a flowchart showing generally the process of extracting and processing the digital signature from the received communication.
  • the communication must be received by the recipient or his computer 302.
  • the recipient must be made aware that the communication contains an embedded digital signature. This is done by displaying 304 the graphic attachment so that the recipient can see it, or, in the case of an audio attachment, playing the attachment so that the recipient hears it . Any transformations which have been applied may themselves be the clue to the recipient that a digital signature has been embedded.
  • the recipient can then ask for validation of the digital signature 306 and the digital signature is extracted from the attachment 308 by reading the bits known to contain the digital signature.
  • the digital signature is verified 310 and the recipient is notified 312 as to whether the signature is valid or not.
  • the extracted digital signature can be displayed 314 for the recipient's viewing.

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Multimedia (AREA)
  • Computer Security & Cryptography (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Human Computer Interaction (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Editing Of Facsimile Originals (AREA)

Abstract

L'invention concerne un procédé d'intégration de signatures numériques par stéganographie dans des annexes graphiques et audio dans la communication électronique, notamment le courrier électronique, les pages du Web, etc. Les destinataires, visualisant les graphiques ou écoutant les annexes audio, connaissent l'existence de la signature numérique intégrée et peuvent demander sa validation. La signature numérique est extraite de l'annexe et validée pour le destinataire.
PCT/US1998/017605 1998-08-25 1998-08-25 Signatures graphiques numeriques WO2000011834A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/US1998/017605 WO2000011834A1 (fr) 1998-08-25 1998-08-25 Signatures graphiques numeriques
AU92943/98A AU9294398A (en) 1998-08-25 1998-08-25 Graphic digital signatures

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US1998/017605 WO2000011834A1 (fr) 1998-08-25 1998-08-25 Signatures graphiques numeriques

Publications (1)

Publication Number Publication Date
WO2000011834A1 true WO2000011834A1 (fr) 2000-03-02

Family

ID=22267743

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1998/017605 WO2000011834A1 (fr) 1998-08-25 1998-08-25 Signatures graphiques numeriques

Country Status (2)

Country Link
AU (1) AU9294398A (fr)
WO (1) WO2000011834A1 (fr)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1168197A2 (fr) * 2000-06-27 2002-01-02 Hitachi, Ltd. Procédé d'affichage d'informations et système de communication utilisant ce procédé
FR2854998A1 (fr) * 2003-05-12 2004-11-19 Picture Certification Com E Signature electronique graphique certification de documents
FR2861519A1 (fr) * 2003-10-24 2005-04-29 Thery Jean Philippe Procede de securisation et verification d'un document etabli et signe par voie electronique ainsi que le dispositif pour la mise en oeuvre de ce procede.
WO2005060152A1 (fr) 2003-12-16 2005-06-30 Sap Aktiengesellschaft Procedes et appareil de signature electronique
US7241617B2 (en) 1998-07-03 2007-07-10 Dnavec Research, Inc. Sendai viral vectors comprising foreign genes inserted between the R1 and R2 Loci
US7457955B2 (en) 2004-01-14 2008-11-25 Brandmail Solutions, Inc. Method and apparatus for trusted branded email
US7502934B2 (en) 2003-12-16 2009-03-10 Sap Aktiengesellschaft Electronic signatures
US7581105B2 (en) 2003-12-16 2009-08-25 Sap Aktiengesellschaft Electronic signing apparatus and methods
US7917761B2 (en) * 2005-03-21 2011-03-29 Microsoft Corporation Digitally signing an electronic document with a user-entered signature image
US7991157B2 (en) 2006-11-16 2011-08-02 Digimarc Corporation Methods and systems responsive to features sensed from imagery or other data

Citations (5)

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Publication number Priority date Publication date Assignee Title
EP0246823A2 (fr) * 1986-05-22 1987-11-25 Racal-Guardata Financial Systems Limited Systèmes et procédés de communication de données
DE4243908A1 (de) * 1992-12-23 1994-06-30 Gao Ges Automation Org Verfahren zur Erzeugung einer digitalen Signatur mit Hilfe eines biometrischen Merkmals
WO1996042151A2 (fr) * 1995-06-07 1996-12-27 The Dice Company Procede et dispositif steganographiques
US5765176A (en) * 1996-09-06 1998-06-09 Xerox Corporation Performing document image management tasks using an iconic image having embedded encoded information
US5781635A (en) * 1995-12-29 1998-07-14 Intel Corporation Method and apparatus for improved digital message transaction model

Patent Citations (5)

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Publication number Priority date Publication date Assignee Title
EP0246823A2 (fr) * 1986-05-22 1987-11-25 Racal-Guardata Financial Systems Limited Systèmes et procédés de communication de données
DE4243908A1 (de) * 1992-12-23 1994-06-30 Gao Ges Automation Org Verfahren zur Erzeugung einer digitalen Signatur mit Hilfe eines biometrischen Merkmals
WO1996042151A2 (fr) * 1995-06-07 1996-12-27 The Dice Company Procede et dispositif steganographiques
US5781635A (en) * 1995-12-29 1998-07-14 Intel Corporation Method and apparatus for improved digital message transaction model
US5765176A (en) * 1996-09-06 1998-06-09 Xerox Corporation Performing document image management tasks using an iconic image having embedded encoded information

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
"AUTHENTICATION AND DISPLAY OF SIGNATURES ON ELECTRONIC DOCUMENTS", RESEARCH DISCLOSURE, no. 358, 1 February 1994 (1994-02-01), pages 75, XP000439803 *

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7241617B2 (en) 1998-07-03 2007-07-10 Dnavec Research, Inc. Sendai viral vectors comprising foreign genes inserted between the R1 and R2 Loci
EP1168197A3 (fr) * 2000-06-27 2004-08-18 Hitachi, Ltd. Procédé d'affichage d'informations et système de communication utilisant ce procédé
EP1168197A2 (fr) * 2000-06-27 2002-01-02 Hitachi, Ltd. Procédé d'affichage d'informations et système de communication utilisant ce procédé
US7010569B2 (en) 2000-06-27 2006-03-07 Hitachi, Ltd. Method of information display and communication system using the method
FR2854998A1 (fr) * 2003-05-12 2004-11-19 Picture Certification Com E Signature electronique graphique certification de documents
FR2861519A1 (fr) * 2003-10-24 2005-04-29 Thery Jean Philippe Procede de securisation et verification d'un document etabli et signe par voie electronique ainsi que le dispositif pour la mise en oeuvre de ce procede.
US7502934B2 (en) 2003-12-16 2009-03-10 Sap Aktiengesellschaft Electronic signatures
WO2005060152A1 (fr) 2003-12-16 2005-06-30 Sap Aktiengesellschaft Procedes et appareil de signature electronique
US7581105B2 (en) 2003-12-16 2009-08-25 Sap Aktiengesellschaft Electronic signing apparatus and methods
US8078878B2 (en) 2003-12-16 2011-12-13 Sap Aktiengesellschaft Securing documents with electronic signatures
US8583931B2 (en) 2003-12-16 2013-11-12 Sap Aktiengesellschaft Electronic signing apparatus and methods
US7457955B2 (en) 2004-01-14 2008-11-25 Brandmail Solutions, Inc. Method and apparatus for trusted branded email
US8621217B2 (en) 2004-01-14 2013-12-31 Jose J. Picazo Separate Property Trust Method and apparatus for trusted branded email
US10298596B2 (en) 2004-01-14 2019-05-21 Jose J. Picazo, Jr. Separate Property Trust Method and apparatus for trusted branded email
US10951629B2 (en) 2004-01-14 2021-03-16 Jose J. Picazo, Jr. Separate Property Trust Method and apparatus for trusted branded email
US11711377B2 (en) 2004-01-14 2023-07-25 Jose J. Picazo, Jr. Separate Property Trust Method and apparatus for trusted branded email
US7917761B2 (en) * 2005-03-21 2011-03-29 Microsoft Corporation Digitally signing an electronic document with a user-entered signature image
US7991157B2 (en) 2006-11-16 2011-08-02 Digimarc Corporation Methods and systems responsive to features sensed from imagery or other data

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