Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N5/00—Details of television systems
  • H04N5/222—Studio circuitry; Studio devices; Studio equipment
  • H04N5/262—Studio circuits, e.g. for mixing, switching-over, change of character of image, other special effects ; Cameras specially adapted for the electronic generation of special effects
  • H04N5/265—Mixing
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
  • G06T1/00—General purpose image data processing
  • G06T1/0021—Image watermarking
  • G06T1/005—Robust watermarking, e.g. average attack or collusion attack resistant
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L63/00—Network architectures or network communication protocols for network security
  • H04L63/12—Applying verification of the received information
• • 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
  • H04N1/32149—Methods relating to embedding, encoding, decoding, detection or retrieval operations
  • H04N1/32154—Transform domain methods
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
  • G06T2201/00—General purpose image data processing
  • G06T2201/005—Image watermarking
  • G06T2201/0052—Embedding of the watermark in the frequency domain
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
  • G06T2201/00—General purpose image data processing
  • G06T2201/005—Image watermarking
  • G06T2201/0065—Extraction of an embedded watermark; Reliable detection
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L2463/00—Additional details relating to network architectures or network communication protocols for network security covered by H04L63/00
  • H04L2463/103—Additional details relating to network architectures or network communication protocols for network security covered by H04L63/00 applying security measure for protecting copyright
• • 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
  • H04N2201/3269—Display, printing, storage or transmission of additional information, e.g. ID code, date and time or title of machine readable codes or marks, e.g. bar codes or glyphs
  • H04N2201/327—Display, printing, storage or transmission of additional information, e.g. ID code, date and time or title of machine readable codes or marks, e.g. bar codes or glyphs which are undetectable to the naked eye, e.g. embedded codes
• • 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
  • H04N2201/3281—Encryption; Ciphering

Definitions

• the present invention relates to the field of watermarking of digital data. It relates more particularly to a system for watermarking data using novel watermark insertion and detection methods as well as to devices for implementing these methods.
• Recent methods for protecting against the illicit copying of digital data use the principle of data watermarking which consists in inserting a marking item, commonly referred to as a "watermark", into a multimedia content (still image, video, sound, etc.) in an lmperceptiole manner.
• the watermark can for example be a signal indicating that the content may not be copied or any other item allowing the supplier of the multimedia content to detect illegal copies.
• the watermark In order to play its role perfectly, the watermark must be robust to transformations of the watermarked content, whether these transformations be made intentionally by a pirate who wishes to erase the watermark, or whether they result from distortions which occurred during the transmission of the signal containing the watermar-ed data.
• Various data watermarking techniques are known from the prior art. Reference may in particular be made to the documents EP-A-0 828 372, EP-A-0 840 513, WO-A- 98/03014 or WO-A-98/54897 which describe methods for inserting watermarks into data to be protected and methods for detecting the presence of such watermarks in the data.
• a scheme which is generally used to describe the principle of data watermarking is that of Figure 1.
• a first part 1 relates to the insertion of a hidden item W (the watermark) into a content to be protected C. This results m a watermarked content CT.
• Part 2 relates to the detection of the presence of the item W in the content received CT.
• An additional datum K is also necessary in the process for inserting ana detecting the ater ar- .
• This datum whicn must be shared in a secret manner by the device for inserting and detecting the watermark is referred to as the key by analogy with so-called symmetric or private-key cryptography systems.
• a known watermarking technique consists in adding a pseudo random noise sequence to data which are to be watermarked.
• the detection process is carried out, in this case, by performing a correlation calculation: the data received are declared watermarked if the correlation with the reference pseudo noise sequence (used for the insertion of the watermark) is greater than a given threshold.
• the reference pseudo noise sequence constitutes the key K of the data watermarking scheme of Figure 1.
• each entity capable of detecting the watermark must share the same key K as the entity which inserted the watermark.
• the entity capable of detecting the watermark can furthermore delete it or modify it, thereby doing away with all the benefit of the initial watermarking of the data. Consequently, a supplier of content protected by watermarking should not communicate his key K, which served for the insertion of the watermark, other than in a secret manner to trusted entities. This considerably limits the possibilities of using data watermarking in numerous fields.
• the invention aims to solve the aforesaid problems.
• the invention relates to a method for inserting a watermark into data representing a content to be protected.
• the method comprises the steps consisting m: a) supplying a pseudo random noise sequence to the input of a filter with predefined impulse response; and b) adding the filtered pseudo noise sequence to the data.
• the method furthermore comprises the steps consisting in: c) performing a pseudo random interleaving of the data before step b) ; and d) performing an inverse interleaving after step b) so as to obtain the watermarked data.
• the invention also relates to a method for detecting a watermark in data representing a content received, characterized in that it comprises the steps consisting in: l) performing a spectral analysis of the data; and ii) deducing therefrom whether the data include a pseudo noise sequence which has been filtered by a filter with predefined spectral response.
• a pseudo random interleaving of the data received, whicn is identical to the interleaving performed m step c) above, is performed before step i) -
• the invention also relates to a system for watermarking data using a watermark insertion method and a watermark detection method as those above.
• a first series of parameters, the private key is used for the insertion of the watermark and a second series of parameters, the public key, is used for the detection of the watermark, so that:
• the invention also relates to a device for inserting a watermark into data representing a content to be protected.
• the device comprises : - means for generating a pseudo random noise sequence;
• - filtering means having a predefined impulse response and which are adapted for receiving the pseudo noise sequence ana for supplying a filtered pseudo noise sequence
• the device furthermore comprises: - first means of pseudo random interleaving of the data representative of the content to be protected so as to supply interleaved data, the interleaved data being supplied to the addition means so as to be added to the filtered pseudo noise sequence; and - means of inverse interleaving of the first interleaving means, linked to the output of the said addition means so as to supply the watermarked data.
• the device comprises: - means for transforming the content to be protected into data representative of the content;
• - multiplication means adapted for receiving, on the one nand the interleaved modulation sequence, and on the other hand the filtered pseudo noise sequence, so as to supply the watermark;
• the invention also relates to a device for detecting a watermark in data representing a content received.
• the device comprises :
• the device furthermore comprises:
• the device furthermore comprises:
• the transforming means being adapted for performing the same transformation as the transforming means of the insertion device.
• FIG. 2 schematically represents a watermark insertion device according to the invention
• FIG. 3 schematically represents a watermark detection device according to the invention
• FIG. 4 illustrates a novel scheme for watermarking digital data according to the invention.
• FIG. 2 Represented schematically in Figure 2 is a device according to the invention for inserting a watermark into a signal representative of a content to be protected.
• This signal can in particular be a digital video or audio signal or else a signal representing a still image such as a photograph or a computer-calculated synthetic image, or more generally, any signal representing a multimedia content.
• the coefficients x n can correspond to the luminance of each pixel of the image.
• These may also be coefficients of a Discrete Fourier Transform of the signal representing the content to be protected, or else coefficients of a Fou ⁇ er-Mellin Transform or coefficients of a wavelet decomposition when tne content to be protected is a still image.
• the module HPM calculates this modulation sequence as a function of algorithms based on human perception models, such as Sarnoff's model of the eye.
• L Linear Time Invariant
• ⁇ w (f) and ⁇ vv (f) respectively represent the power spectral densities of (fK n , ( ⁇ ) and ⁇ w ⁇ ) , that is to say their Fourier Transforms.
• the filtered pseudo noise sequence w is multiplied (multiplier 18) by the interleaved modulation sequence m and the resulting sequence, which constitutes the watermark, is added (adder 22) to tne sequence of interleaved data x.
• a transformation inverse to that performed by the transformation module 10 is then performed by the module 26 so as to obtain the marked content (or watermarked content) which is thus protected against illicit copying without the watermark being perceptible within the content.
• the principle of the detection is based on the spectral analysis of tne signal received.
• the signal received is representative of the received content for which one will seek to determine whether or not it is watermarked. This content is of the same type as the content to be protected described previously. In the example which follows, it will be assumed that the content received is an image containing N pixels.
• the luminances r n of the pixels of the image received are obtained as output from the transformation module 30.
• the data sequence r Since the watermark has been inserted, m the device of Figure 2, into a sequence of interleaved data x, the data sequence r will, in order to detect the possible presence of a watermark in the content received, be transmitted to an interleaver 32 performing the same permutation p of the coefficients r n as that performed by the mterleavers 20 and 14 of Figure 2.
• a sequence of interleaved data r ⁇ r p(n) ⁇ is obtained as output from the interleaver 32.
• the interleaving of the data sequence x and of the modulation sequence m will now be apparent. Indeed, if the data sequence x represents the pixels of an image, its spectral density has a very structured shape with very large amplitude differences.
• the role of the interleaving of the data is to sever the statistical coherence of this sequence so that the spectral density of the sequence of interleaved data x has a substantially flat shape, such as that of a pseudo noise sequence with Gaussian distribution.
• the nodule 36 tests the likelihood of two hypotheses:
• ⁇ v is equal to 1, but one may equally choose other values.
• ⁇ m is normed at the level of the insertion device and equals for example 3.
• the mo ⁇ ule 36 calculates two numoers r H( o(r) and U N( ⁇ (r) representing the likelihoods of the hypotheses
• the module 36 deduces from this: if U N , i ( r ) >U N ,o ( ⁇ ) , then the response of the detector is "Y" signifying that the content received is watermarked; and
• a parameter whicn is referred to as the "private key” K PRI is used for the insertion (100) of a watermark W into a content C
• another parameter which is referred to as the "public key” K PUB is used for the detection (200) of a watermark in a content received CT.
• the terms "private key” and "public key” are used by analogy with public key crytographic systems. It will be noted that here the watermark W is binary, that is to say that, either the content C is watermarked, or it is not, but W does not contain any item of its own.
• the private key K PRI is formed by the pseudo random noise sequence v as well as by the impulse response h of the filter 16 (Fig. 2) .
• the public key used to detect the watermark in the content received is for its part formed from the modulus of the spectral response of the filter 16

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• Engineering & Computer Science (AREA)
• Signal Processing (AREA)
• Multimedia (AREA)
• Computer Security & Cryptography (AREA)
• Theoretical Computer Science (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Computer Hardware Design (AREA)
• Computing Systems (AREA)
• General Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Editing Of Facsimile Originals (AREA)
• Image Processing (AREA)
• Television Systems (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

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Cited By (5)

Families Citing this family (11)

Citations (4)

Family Cites Families (12)

• 1999
  • 1999-06-01 FR FR9907139A patent/FR2794600B1/fr not_active Expired - Fee Related
• 2000
  • 2000-05-05 DE DE60012515T patent/DE60012515T2/de not_active Expired - Lifetime
  • 2000-05-05 US US09/926,585 patent/US7031492B1/en not_active Expired - Lifetime
  • 2000-05-05 EP EP00929504A patent/EP1181810B1/en not_active Expired - Lifetime
  • 2000-05-05 WO PCT/EP2000/004053 patent/WO2000074371A1/en not_active Ceased
  • 2000-05-05 JP JP2001500546A patent/JP2003529957A/ja not_active Withdrawn
  • 2000-05-05 CN CNB008081743A patent/CN1157048C/zh not_active Expired - Lifetime
  • 2000-05-05 ES ES00929504T patent/ES2225137T3/es not_active Expired - Lifetime
  • 2000-05-05 AU AU47557/00A patent/AU4755700A/en not_active Abandoned
  • 2000-05-19 TW TW089109631A patent/TW465224B/zh not_active IP Right Cessation
  • 2000-05-31 MY MYPI20002450A patent/MY123704A/en unknown

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