Electric Signal Masking Patents (Class 380/252)
  • Patent number: 7333965
    Abstract: Multiple independent classifiers of a code editor are used to classify a range of text. Each classifier is an independent classifier and can independently classify any given range of text. Classifiers can be added and merged during run time of the code editor. Adding a classifier does not require modification of any existing classifiers in the code editor. Text can be classified and formatted in accordance with any number of classifiers in the aggregate. The user of the code editor can initiate classification. The user of the code editor can select text for user specific formatting.
    Type: Grant
    Filed: February 23, 2006
    Date of Patent: February 19, 2008
    Assignee: Microsoft Corporation
    Inventors: John S. Tilford, Randy S. Kimmerly, Vijaye G. Raji
  • Patent number: 7324646
    Abstract: A method and apparatus is disclosed for introducing alterations or distortions in projected images. The distortions on the projected image are imperceptible to a human viewer. The distortions are recorded on recording devices and observable upon viewing the recorded images.
    Type: Grant
    Filed: June 9, 2000
    Date of Patent: January 29, 2008
    Assignee: Sarnoff Corporation
    Inventors: Herschel Clement Burstyn, George Herbert Needham Riddle, Leon Shapiro, David Lloyd Staebler
  • Patent number: 7305089
    Abstract: The camera includes a sensor for sensing the photographer's iris image and registering the image in advance. The iris image is recorded in the image of a subject by a digital MCU at a timing different from that at which the image of the subject is captured. The recording timing is that at which the camera power supply is turned off, that at which a recording medium is ejected from the camera or that at which the iris image to be recorded is changed to the registered iris image of another photographer. The recording of the iris image is achieved by embedding it as a watermark or by appending it to metadata.
    Type: Grant
    Filed: June 13, 2003
    Date of Patent: December 4, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Goichi Morikawa, Go Tokura
  • Patent number: 7290141
    Abstract: A method and system for authenticating messages received from users across multiple remote devices are provided. A residential gateway authenticates a user using a modified digest authentication scheme by storing a sequence number in the nonce field. Access encryption keys and sequence number spaces may be assigned based on user or on user/remote device pairs. When sequence number spaces are assigned based on user, and the user uses multiple remote devices to access the residential gateway, the sequence number space may be divided into mini-sequence number spaces for each of the multiple remote devices. Access encryption may be two-tiered, such that a secondary key is generated based on a user's primary key, and the secondary key is only valid for a limited amount of time before it expires and a new secondary key must be generated.
    Type: Grant
    Filed: June 27, 2002
    Date of Patent: October 30, 2007
    Assignee: Nokia, Inc.
    Inventors: Senthil Sengodan, Tat Chan
  • Patent number: 7277871
    Abstract: A digital watermark embedding apparatus generates an echo signal, which is delayed a time period corresponding to digital watermark information to be embedded with respect to each tone signal that forms an original audio signal, and inserts the generated echo signal in the original audio signal by spreading the echo signal on the time axis, thus outputting a watermarked audio signal. A digital watermark detection apparatus despreads echo signals contained in the watermarked audio signal on the time axis, and extracts digital watermark information from the generation time of the despread echo signal contained in the watermarked audio signal.
    Type: Grant
    Filed: November 8, 2002
    Date of Patent: October 2, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoiti Suzuki, Ryouichi Nishimura
  • Patent number: 7251327
    Abstract: A system control circuit 5 determines whether or not an external apparatus connected to an interface 14 is one that can store data, by transmitting data to the apparatus through the interface 14. It the system control circuit 5 determines that the external apparatus can store data, the circuit 5 turns off a switch 13, stopping the transmission of audio data to the external apparatus through the interface 14. As a result, illegal copying of the data can be effectively prevented.
    Type: Grant
    Filed: October 14, 1999
    Date of Patent: July 31, 2007
    Assignee: Sony Corporation
    Inventors: Yoichiro Sako, Tatsuya Inokuchi, Masayuki Obata, Shuichi Ito, Kazuko Sakurai
  • Patent number: 7239707
    Abstract: A transmitter employing a cryptographic algorithm and key generates and transmits a staggered pulse signal that includes a plurality of high-power pulses that are part of a pseudonoise (PN) code. The high-power pulses are separated by a group of low-power chips and the time interval between the high-power pulses is varied according to the cryptographic algorithm and key. A receiver, employing a corresponding cryptographic algorithm and key receives the signal and correlates it with a locally generated code that is modified according to the cryptographic algorithm and key to detect the phase of the received PN code. The receiver also can include a matched filter configured according to the cryptographic algorithm and key to detect the sequence of high-power pulses in the received signal.
    Type: Grant
    Filed: November 28, 2001
    Date of Patent: July 3, 2007
    Assignee: ITT Manufacturing Enterprises, Inc.
    Inventors: Gene L. Cangiani, Peter M. Brodie, James M. Clark, Dennis McCrady
  • Patent number: 7231271
    Abstract: Method for embedding a covert message within a digital audio signal. The existence of the covert message is undetectable and the information content of the covert message can be further rendered unascertainable. Covert message data is embedded within a digital audio signal on an audio frame-by-audio frame basis. Covert message data is embedded either at a rate of one bit per frame or two bits per frame. The invention has uses including but not limited to watermarking digital audio signals, hiding data within a digital audio signal, increasing the channel capacity of a communications channel by placing multiple messages within each other, and generally increasing message robustness.
    Type: Grant
    Filed: January 21, 2004
    Date of Patent: June 12, 2007
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Kaliappan Gopalan, Stanley J. Wenndt, Darren Haddad
  • Patent number: 7190792
    Abstract: Systems and methods are disclosed for using an arbitrary fixed channel to carry third-party information. In one embodiment, the present invention provides systems and methods for enabling existing content rendering devices to accept content encoded in a proprietary format, such as an encoding format used by a digital rights management system. The encoded content is rendered by the device in the normal manner, and decoded by a retrofitting appliance connected to the device's output. The retrofitting appliance may apply decoded rules and controls to the decoded content, thereby managing use of the content.
    Type: Grant
    Filed: April 4, 2006
    Date of Patent: March 13, 2007
    Assignee: Intertrust Technologies Corp.
    Inventor: Talal G Shamoon
  • Patent number: 7181022
    Abstract: Methods of processing audio to convey auxiliary information therein without audible evidence of data alteration. Various arrangements are disclosed. One receives plural bit auxiliary data in which the auxiliary information is included, and modulates a carrier signal with the auxiliary data to yield intermediate data. The intermediate data is then summed with the original audio to produce the encoded audio. The carrier signal can be tailored to enhance performance, and the intermediate data can be scaled in amplitude so as to better hide the auxiliary data within the audio. One application of the technology is in monitoring, where the auxiliary information can be used to track usage of audio or audio-visual content.
    Type: Grant
    Filed: March 25, 2003
    Date of Patent: February 20, 2007
    Assignee: Digimarc Corporation
    Inventor: Geoffrey B. Rhoads
  • Patent number: 7177429
    Abstract: A system and methods for permitting open access to data objects and for securing data within the data objects is disclosed. According to one embodiment of the present invention, a method for securing a data object is disclosed. According to one embodiment of the present invention, a method for securing a data object is disclosed. The method includes the steps of (1) providing a data object comprising digital data and file format information; (2) embedding independent data into a data object; and (3) scrambling the data object to degrade the data object to a predetermined signal quality level. The steps of embedding and scrambling may be performed until a predetermined condition is met. The method may also include the steps of descrambling the data object to upgrade the data object to a predetermined signal quality level, and decoding the embedded independent data. The additional steps of descrambling and decoding may be performed until a predetermined condition is met.
    Type: Grant
    Filed: December 7, 2000
    Date of Patent: February 13, 2007
    Assignee: Blue Spike, Inc.
    Inventors: Scott A. Moskowitz, Michael W. Berry
  • Patent number: 7177430
    Abstract: The present invention provides a system and method for introducing white noises into a digital audio signal so that there is progressive and cumulative degradation in audio quality after each successive reproduction of the audio sound signal in a fashion analogous to analog audio reproduction. The invention provides a white noise generator, and a digital entroping unit. In a preferred embodiment, the white noise generator is implemented by a hardware random number generator. The digital entroping unit controls the magnitude of white noise desired based on a random number generated by the random number generator, and adds the white noise to the input audio sound signal to produce a degraded audio sound signal. The magnitude of white noise can be controlled by using various masking and formatting of random number data.
    Type: Grant
    Filed: October 31, 2001
    Date of Patent: February 13, 2007
    Assignee: Portalplayer, Inc.
    Inventor: Jason Seung-Min Kim
  • Patent number: 7146503
    Abstract: A system and method of generating a watermarked signal are disclosed. The system segments the signal into overlapping blocks using a window function and processes the overlapping blocks according to whether each block is odd- or even-numbered. The system windows the odd-numbered blocks, modulates the phase of each block in the frequency domain, transforms each modulated block in the time domain, windows each block transformed into the time domain and overlap-adds each odd-numbered block with each even-numbered block to generate the watermarked signal.
    Type: Grant
    Filed: March 26, 2002
    Date of Patent: December 5, 2006
    Assignee: AT&T Corp.
    Inventors: James David Johnston, Shyh-Shiaw Kuo, Schuyler Reynier Quackenbush, William Turin
  • Patent number: 7142670
    Abstract: Methods, apparatus and computer software and hardware products providing method, apparatus and system solutions for implementing table lookups in a side-channel attack resistant manner. Embodiments are provided for devices and situations where there is limited amount of RAM memory available or restrictions on memory addressing. The solutions solve problems associated with look up tables with large indices, as well as problems associated with looking up large sized tables or a collection of tables of large cumulative size, in limited devices, in an efficient side-channel attack resistant manner. These solutions provide defenses against both first-order side channel attacks as well as higher-order side channel attacks. One aspect of the present invention is the creation of one or more random tables which are used possibly in conjunction with other tables to perform a table lookup.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: November 28, 2006
    Assignee: International Business Machines Corporation
    Inventors: Suresh N. Chari, Josyula R. Rao, Pankaj Rohatgi, Helmut Scherzer
  • Patent number: 7140037
    Abstract: A signal (801) of a first code string made through replacing a part of a code string of a predetermined format with dummy data is sent to code string rewriting means (1802) via code string resolution means (1801). A signal (806) of a second code string for complementing the dummy data part in the signal (801) is sent to the code string rewriting means (1802) via control means (1805) and the dummy data in the first code string is rewritten to the second code string. At the time of trial viewing/listening, a signal (802) from the code string resolution means (1801) is selected by a switch (1808), and when the second code string (806) is acquired through content purchase, a signal (803) from the code string rewriting means (1802) is selected by the switch (1808). Thus, trial viewing/listening of a content such as music is made possible while the possibility of decryption is eliminated. By acquiring a relatively small quantity of data, reproduction of a high-quality content is made possible.
    Type: Grant
    Filed: February 8, 2002
    Date of Patent: November 21, 2006
    Assignee: Sony Corporation
    Inventors: Kyoya Tsutsui, Tadao Yoshida, Kenzo Akagiri, Naoya Haneda
  • Patent number: 7131007
    Abstract: A system and method of retrieving a watermark in a watermarked signal are disclosed. The watermarked signal comprises odd and even overlapped blocks where the watermark is contained in the even blocks. The method comprises, for each k-th even block, subtracting the two adjacent odd blocks from the k-th even block of the watermarked signal to retrieve {overscore (s)}*k(n), transforming {overscore (s)}*k(n) into the frequency domain to generate {overscore (S)}k(f), calculating a phase of {overscore (S)}k(f) as {overscore (?)}(f) and a phase of Sk(f) as ?(f), calculating the difference ?(f) between {overscore (?)}(f) and ?(f), unwrapping ?(f) to obtain the phase modulation {tilde over (?)}k(f), and using a Viterbi search to retrieve the watermark embedded in {tilde over (?)}k(f).
    Type: Grant
    Filed: March 26, 2002
    Date of Patent: October 31, 2006
    Assignee: AT & T Corp.
    Inventors: James David Johnston, Shyh-Shiaw Kuo, Schuyler Reynier Quackenbush, William Turin
  • Patent number: 7127620
    Abstract: A coding device for implementing a cryptographic encryption and/or access authorization includes a data processing unit, a decoupling unit, a power supply interface, a main clock supply unit, and a power profile generator generating a power profile and superimposing it on a power profile of the data processing unit to prevent an attack by correlation analysis of the power profile.
    Type: Grant
    Filed: May 3, 2002
    Date of Patent: October 24, 2006
    Assignee: Infineon Technologies AG
    Inventor: Gregor Boeckeler
  • Patent number: 7124442
    Abstract: A system for the insertion of microthreads in transmitted data is provided. The system includes a digital content system providing carrier data, such as sampled audio data. A microthread insertion system coupled to the digital content system generates a composite data sequence that includes the carrier data and microthread data, such as broadcast verification data. The microthread data is camouflaged using the carrier data, such as by including in the audio signal in a manner that allows it to be detected but which does not noticeably affect the audio signal for listeners.
    Type: Grant
    Filed: July 25, 2001
    Date of Patent: October 17, 2006
    Assignee: 440 Pammel, Inc.
    Inventor: Jon Nash-Putnam
  • Patent number: 7046808
    Abstract: A system for determining the amount of processing that has been applied to watermarked signal. A steganographic signal is provided that includes an original signal and an embedded fragile watermark. The fragile watermark is characterized by a low energy and a high redundancy in comparison to a robust watermark. The steganographic signal is communicated over a distribution channel to a decoder. At the decoder, a measure of a presence of the fragile watermark in the acquired steganographic signal is provided, along with an estimate of the fragility profile of the fragile watermark for this particular original signal. Based on these factors, a estimate is made of the amount of processing that the steganographic signal has undergone. This processing can include, for example, A/D and D/A conversions, resampling, band-limiting, perceptual compression/decompression, etc.
    Type: Grant
    Filed: March 24, 2000
    Date of Patent: May 16, 2006
    Assignee: Verance Corporation
    Inventors: Eric Metois, Rade Petrovic, Kanaan Jemili
  • Patent number: 7043022
    Abstract: A transmitter adds packet transmission order information to transmitted packets using a forward error device (416) and a masking device (420). The masking device (420) receives ordering masks (610) from a mask store (424). The ordering masks (610) are maintained in a known order, and the ordering masks (610) and the known order are known to both the transmitter and the receiver. The receiver includes an unmasking device (504) that applies ordering masks to unmask the packets, and then an error detection device checks for errors. The ordering masks (610) are applied in the known order until errors are below an acceptable limit. When errors are below an acceptable limit, the relative packet order is determined from the known order of the ordering masks.
    Type: Grant
    Filed: November 22, 1999
    Date of Patent: May 9, 2006
    Assignee: Motorola, Inc.
    Inventors: Scott D. Blanchard, Dean P. Vanden Heuvel
  • Patent number: 7043019
    Abstract: An apparatus and method for displaying a copy-deterrent pattern (104) within a digital motion picture in order to discourage recording of the motion picture using a video camera or other sampling recording device. A copy-deterrent pattern (104) could be, for example, one or more symbols, a random pattern, a digital watermark or a text message (106). The copy-deterrent pattern (104) comprises a plurality of pixels within each frame of the digital motion picture, and the displayed pixel intensities are modulated at a temporal frequency using modulation characteristics deliberately selected to be imperceptible to human observers while simultaneously producing objectionable aliasing in any copy made using a video camera.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: May 9, 2006
    Assignee: Eastman Kodak Company
    Inventors: Babak Tehranchi, Paul W. Jones
  • Patent number: 7039614
    Abstract: In accordance with one embodiment, a method for storing a normal scrambled digital program is provided. The method includes receiving a scrambled program, and receiving a plurality of access requirements. Each access requirement can descramble the scrambled program. The method also includes selecting at least one of the access requirements, and storing the scrambled program and the selected requirement.
    Type: Grant
    Filed: November 9, 1999
    Date of Patent: May 2, 2006
    Assignees: Sony Corporation, Sony Electronics, Inc.
    Inventor: Brant L. Candelore
  • Patent number: 7024175
    Abstract: A system to thwart eavesdropping on microphonic audio signals generated by a powered telecommunications device connected to a communications line, comprising a noise generator for applying low level noise to the line, thereby masking microphonic audio signals, and a disconnect circuit for disconnecting the telecommunications device from the line in the absence of power to the telecommunications device.
    Type: Grant
    Filed: May 16, 2000
    Date of Patent: April 4, 2006
    Assignee: Mitel Corporation
    Inventors: Philippe Moquin, Bipin Pillay
  • Patent number: 7020281
    Abstract: A method for determining a result of a group operation performed an integral number of times on a selected element of the group, the method comprises the steps of representing the integral number as a binary vector; initializing an intermediate element to the group identity element; selecting successive bits, beginning with a left most bit, of the vector. For each of the selected bits; performing the group operation on the intermediate element to derive a new intermediate element; replacing the intermediate element with the new intermediate element; performing the group operation on the intermediate element and an element, selected from the group consisting of: the group element if the selected bit is a one; and an inverse element of the group element if the selected bit is a zero; replacing the intermediate element with the new intermediate element.
    Type: Grant
    Filed: January 18, 2001
    Date of Patent: March 28, 2006
    Assignee: Certicom Corp.
    Inventors: Ashok Vadekar, Robert J. Lambert
  • Patent number: 7003118
    Abstract: An architecture for a high performance IPSEC accelerator. The architecture includes components for scanning fields of packets, programming an IPSEC services device according to the scanned fields, and modifying the scanned packet with an output from the IPSEC security services device. Preferably, the architecture is implemented in hardware, and attached to a host machine. Hardware devices, fast in comparison to software processing and network speeds, allows the computationally intensive IPSEC processes to be completed in real-time and reduce or eliminate bottlenecks in the path of a packet being sent or received to/from a network.
    Type: Grant
    Filed: November 27, 2000
    Date of Patent: February 21, 2006
    Assignee: 3Com Corporation
    Inventors: Li-Jau (Steven) Yang, Chi-Lie Wang, Kap Soh, Chin-Li (Karen) Mou
  • Patent number: 6996237
    Abstract: Apparatus and methods for including a code having at least one code frequency component in an audio signal are provided. The abilities of various frequency components in the audio signal to mask the code frequency component to human hearing are evaluated and based on these evaluations an amplitude is assigned to the code frequency component. Methods and apparatus for detecting a code in an encoded audio signal are also provided. A code frequency component in the encoded audio signal is detected based on an expected code amplitude or on a noise amplitude within a range of audio frequencies including the frequency of the code component.
    Type: Grant
    Filed: July 12, 2002
    Date of Patent: February 7, 2006
    Assignee: Arbitron Inc.
    Inventors: James M. Jensen, Wendell D. Lynch, Michael M. Perelshteyn, Robert B. Graybill, Sayed Hassan, Wayne Sabin
  • Patent number: 6993133
    Abstract: A data recording and reproduction apparatus is provided with a stream attribute decision means for deciding whether an audio data stream supplied from an outside source is compressed or not. A compression ID flag having a value according to the result of the compression decision is attached to the audio data stream, and the flag-attached audio data stream is written in a stream storage unit. Therefore, a watermark can be inserted in a compressed audio data stream after reading the compressed audio data stream from the stream storage unit, whereby the time required for writing the compressed audio data stream in the stream storage unit is reduced, and the quality of analog audio data obtained by reproducing the compressed audio data stream is prevented from being degraded.
    Type: Grant
    Filed: October 8, 1999
    Date of Patent: January 31, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tomoyuki Nonomura, Mitsuhiro Inoue, Masataka Minami, Masayuki Kozuka
  • Patent number: 6983051
    Abstract: An identification code signal is hidden in a carrier signal (such as an electronic data signal or a physical medium) in a manner that permits the identification signal later to be discerned. The carrier signal can thereby be identified, or some machine responsive action can thereby be taken. The technique can be applied in video imagery embodiments to control associated video equipment, e.g. to serve as a copy control signal.
    Type: Grant
    Filed: January 18, 2000
    Date of Patent: January 3, 2006
    Assignee: Digimarc Corporation
    Inventor: Geoffrey B. Rhoads
  • Patent number: 6954541
    Abstract: A method of editing a digital image having associated embedded data, such as printing hints, includes embedding a first watermark in the original image before the image is edited. The first watermarking scheme associates first watermark information with each pixel and is used to detect which pixels have been edited. A second watermark may be embedded in the original image according to a second watermarking scheme which associates second watermark information with non-overlapping groups of pixels in the original image. The second watermark information may be used to synchronize the first watermark information and to detect editing information which does not change pixel values. After editing, only those edited portions of the image need have their embedded data reapplied.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: October 11, 2005
    Assignee: Xerox Corporation
    Inventors: Zhigang Fan, Hui Cheng, Robert J. Rolleston
  • Patent number: 6931527
    Abstract: The invention concerns a method and system for safely transmitting a fax between a transmitter sending the fax and at least a receiver (11) receiving the fax (162) using a fax machine (161) associated with a telephone equipment (16). The faxes (162) are routed between a transmitter and a receiver by a communication network (15) via a fax management center (30). The fax management center (30) provides the receiver (11) with a card, formatted like a credit card, personalized by specific identifiers for each card and each receiver. This card (10) emits brief identifying sound signals, of the DTMF type, at least partially encrypted, varying with each operation, when it is actuated (14) by the receiver (11). The signals received by the microphone (17) of the telephone equipment (16) are transmitted by the communication network (15) to the computer services (18) of the fax management center (30).
    Type: Grant
    Filed: September 25, 1997
    Date of Patent: August 16, 2005
    Assignee: Fintel S.A.
    Inventors: Franck Rosset, Alain Gayet, Jean Moulin
  • Patent number: 6915002
    Abstract: A watermark embedder encodes auxiliary information, such as a binary message, into a host media signal by modulating message signals with two or more corresponding carrier signals to form a watermark signal and embeds this signal into the host. A compatible watermark decoder uses the carrier signals to demodulate the message signals from the watermarked signal.
    Type: Grant
    Filed: July 14, 2003
    Date of Patent: July 5, 2005
    Assignee: Digimarc Corporation
    Inventor: Ammon E. Gustafson
  • Patent number: 6901514
    Abstract: A method for embedding a watermark into content is disclosed. The content contains content samples. The method including the steps of: receiving the content, creating a continuous watermark sequence from the watermark, and for each content sample in a first predetermined order: calculating a sample mean, calculating a sample variance, and normalizing the content. Further steps include generating a set of content coefficients from the content, generating a set of watermark coefficients from the watermark sequence, embedding the watermark in the content by adjusting the amplitude of the watermark coefficients so that the distortion between the content coefficients and the associated watermark coefficients are minimized using a secret mapping function, and outputting the content. The mapping functions may be controlled by a key-dependent random sequence to protect the watermarks.
    Type: Grant
    Filed: June 1, 2000
    Date of Patent: May 31, 2005
    Assignee: Digital Video Express, L.P.
    Inventors: Siu-Leong Iu, Wai Chu
  • Patent number: 6850252
    Abstract: An intelligent electronic appliance preferably includes a user interface, data input and/or output port, and an intelligent processor. A preferred embodiment comprises a set top box for interacting with broadband media streams, with an adaptive user interface, content-based media processing and/or media metadata processing, and telecommunications integration. An adaptive user interface models the user, by observation, feedback, and/or explicit input, and presents a user interface and/or executes functions based on the user model. A content-based media processing system analyzes media content, for example audio and video, to understand the content, for example to generate content-descriptive metadata. A media metadata processing system operates on locally or remotely generated metadata to process the media in accordance with the metadata, which may be, for example, an electronic program guide, MPEG 7 data, and/or automatically generated format.
    Type: Grant
    Filed: October 5, 2000
    Date of Patent: February 1, 2005
    Inventor: Steven M. Hoffberg
  • Patent number: 6842522
    Abstract: A method for recoding data on an optical medium such as DVD. The method includes receiving main data from a data source, determining a plurality of data frame values in response to the main data, inverting at least one selected bit in at least one of the data frame values to generate a plurality of encoded data frames, scrambling the encoded data frames by a feedback shift register to generate scrambled data frames, generating ECC values in response to the scrambled data frames, adding the ECC values to the scrambled data frames to generate an ECC block, rearranging the ECC block to generate a plurality of recording frames, encoding the recording frame by an eight-to-sixteen modulation (ESM) encoder to generate code words, adding sync values to the code words to generate a plurality of physical sectors, and recording the physical sectors on the optical medium. There is a complementary method for reading and decoding data from an optical medium.
    Type: Grant
    Filed: June 1, 2000
    Date of Patent: January 11, 2005
    Assignee: Macrovision Corporation
    Inventor: Daniel Downing
  • Patent number: 6813695
    Abstract: A cache memory serves for accelerating accesses to an external memory of a microprocessor. Instead of an actually occurring hit event, a cache miss is signaled to the microprocessor. The reversal is randomly controlled. This disguises the current profile of cache hit and miss events, which enhances the security against statistical attack techniques based on the evaluation of the current profile.
    Type: Grant
    Filed: July 11, 2002
    Date of Patent: November 2, 2004
    Assignee: Infineon Technologies AG
    Inventors: Berndt Gammel, Michael Smola
  • Publication number: 20040170279
    Abstract: A method of decompressing data words of an instruction set includes:
    Type: Application
    Filed: December 2, 2003
    Publication date: September 2, 2004
    Applicant: Broadcom Corporation
    Inventors: Sophie Wilson, John Redford
  • Patent number: 6778682
    Abstract: The present invention relates to a data hiding method that includes changing values of input pixels corresponding to an input two-dimensional image to encode an N-bit auxiliary data signal therein, thereby yielding encoded output pixels defining an encoded output image. N comprises at least two. The method is characterized in that the N-bit auxiliary data signal is redundantly encoded in the image by at least: changing values of input pixels in a first image location according to a first pattern in order to encode the N-bit auxiliary data signal therein; changing the pattern according to a key to yield a second pattern; and changing values in a second image location according to the second pattern in order to encode the N-bit auxiliary data signal therein.
    Type: Grant
    Filed: July 31, 2002
    Date of Patent: August 17, 2004
    Assignee: Digimarc Corporation
    Inventor: Geoffrey B. Rhoads
  • Patent number: 6775557
    Abstract: A telephone and telephone answering apparatus and method are described for using secondary information embedded in audio passages included in phone calls. The telephone and telephone answering device monitors received calls to automatically detect for the presence of embedded secondary information. Some embodiments merely receive, automatically monitor for the presence of, and use secondary information. Other embodiments are also capable of generating and of embedding secondary information into audio passages.
    Type: Grant
    Filed: May 5, 2001
    Date of Patent: August 10, 2004
    Inventor: Irving Tsai
  • Patent number: 6768808
    Abstract: A content object is steganographically encoded with plural-bit decryption instruction data. A recipient can decode this decryption data, and apply it to the content.
    Type: Grant
    Filed: December 9, 2002
    Date of Patent: July 27, 2004
    Assignee: Digimarc Corporation
    Inventor: Geoffrey B. Rhoads
  • Publication number: 20040139324
    Abstract: The present invention discloses an apparatus for authentication, prevention of forgery/alteration of data recorded by digital voice recorder (DVR) and method thereof. A forgery or alteration prevention unit is installed inside the digital voice recorder or inside the PC connected to the digital voice recorder. The forgery or alteration prevention unit goes through a process to prevent forgery/alteration before audio data is recorded by the digital voice recorder or before audio data is stored at the data storage unit inside the PC. This can be performed by embedding watermark into audio data, by encrypting audio data by a predetermined encryption key, or by inserting a hash value into the audio data. Accordingly, forgery/alteration of audio data recorded by digital voice recorder can be verified.
    Type: Application
    Filed: October 14, 2003
    Publication date: July 15, 2004
    Inventors: Dong-Hwan Shin, Jin-Ho Yoon, Young-Ho Choi, Jong-Uk Choi
  • Patent number: 6760438
    Abstract: A system and method for Viterbi decoding on encrypted data is disclosed. At the receiver, maximum likelihood decoding is performed based on received input in the encryption domain. When selecting a path from one stage of a Viterbi decoding trellis to the next, a local metric may be associated with each of the possible paths based on Euclidean distance between a received symbol and a path state. The path state is determined by encrypting the binary path state. An overall metric is associated with each state equivalent to a sum of local path metrics along a survivor path of selected paths. At the end of the Viterbi decoding trellis, a decoded and decrypted bit sequence is obtained by tracing back in a conventional manner.
    Type: Grant
    Filed: July 1, 1999
    Date of Patent: July 6, 2004
    Assignee: Nortel Networks Limited
    Inventors: Yan Hui, Karl D. Mann
  • Patent number: 6754364
    Abstract: Methods and systems for fingerprinting digital data are described. In the described embodiment, Direct Sequence Spread Spectrum (DSSS) technology is utilized. Unique fingerprinting words are defined where each includes at least one spread sequence. In the described embodiment, a fingerprinting word comprises a plurality symbols, called “&Ggr; symbols.” Each &Ggr; symbol is composed of 2c-1 blocks, where c represents the number of colluders that are desired to be protected against. Each block contains d spread sequence chips. The fingerprinting words are assigned to a plurality of entities to which protected objects embedded with the fingerprinting words are to be distributed. To ascertain the identity of an entity that has altered its unique fingerprinting word, the relative weight of each block is computed in accordance with a defined function and blocks whose weights satisfy a predetermined relationship are “clipped” to a so-called working range.
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: June 22, 2004
    Assignee: Microsoft Corporation
    Inventor: Yacov Yacobi
  • Patent number: 6721423
    Abstract: A set of methods is specified whereby software reduces compromising electromagnetic emanations of computers that could otherwise allow eavesdroppers to reconstruct sensitive processed data using periodic averaging techniques. Fonts for screen display of text are low-pass filtered to attenuate those spectral components that radiate most strongly, without significantly affecting the readability of the text, while the character glyphs displayed are chosen at random from sets that are visually equivalent but that radiate differently. Keyboard microcontroller scan loops are also furnished with random variations that hinder reconstruction of the signal emanated by a keyboard. Drivers for hard disks and other mass-storage devices ensure that the read head is never parked over confidential data longer than necessary.
    Type: Grant
    Filed: January 28, 1999
    Date of Patent: April 13, 2004
    Inventors: Ross J. Anderson, Markus Guenther Kuhn
  • Patent number: 6707930
    Abstract: The invention relates to a method of embedding a watermark W in an information signal P, to a corresponding arrangement for embedding a watermark W in an information signal P, to an information signal with an embedded watermark, and to a storage medium 50 having stored thereon an information signal P with an embedded watermark W. The watermark is embedded in the information signal by deriving sub-patterns Wi from said watermark pattern W, wherein the energy spectrum concentration of each sub-pattern Wi has a dominent orientation. The local weight factors &lgr;(P) for said watermark sub-patterns Wi are determined based on the local energy spectrum of the information signal P in said dominent orientation. Said watermark sub-patterns Wi are locally weighted using said determined local weight factors &lgr;(P). Finally, the locally weighted watermark sub-patterns (Wi) are added to the information signal P.
    Type: Grant
    Filed: November 2, 2001
    Date of Patent: March 16, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Antonius Adrianus Cornelis Maria Kalker, Jaap Andre Haitsma
  • Publication number: 20040042619
    Abstract: An analog signal scrambling/descrambling method is intended to have the higher encryption durability and applicability to the international telephone and shortwave radio communication which rely on low-quality transmission links. The scrambling and descrambling processes use FIR filters for implementing the linear convolution of input signals, delay means, constant number generation means, adders and multipliers. The constant number generation means produce outputs that are non-zero and smaller than 1 in absolute value, one FIR filter used for one of the scrambling process and descrambling process has a filter factor h which is generated based on the discrete Fourier transform, and another FIR filter used for another process has a filter factor that is the time-reverse version of the filter factor h.
    Type: Application
    Filed: September 3, 2002
    Publication date: March 4, 2004
    Inventor: Akio Yamaguchi
  • Patent number: 6683958
    Abstract: Apparatus and methods are provided for embedding or embedding digital data into an analog host or cover signal. A distributed signal feature of the cover signal in a particular domain (time, frequency or space) is calculated and compared with a set of predefined quantization values corresponding to an information symbol to be encoded. The amount of change required to modify the signal feature to the determined target quantization value is calculated and the cover signal is modified accordingly to so change the feature value over a predefined interval. Information symbols are extracted by the opposite process. In one embodiment, the predefined value is a short term autocorrelation value of the cover signal.
    Type: Grant
    Filed: July 29, 2002
    Date of Patent: January 27, 2004
    Assignee: Verance Corporation
    Inventor: Rade Petrovic
  • Patent number: 6675146
    Abstract: An input content signal—representing audio or video—is encoded to hide plural-bit auxiliary data therein. The process generates an intermediate signal that is a function of (a) the plural-bit auxiliary data, and (b) data related to human perception attributes of the content signal. This intermediate signal is then summed with the content signal to effect encoding. The plural-bit auxiliary data can include copy control data, i.e., data that can be sensed by a consumer electronic device and used to disable a copying operation. The intermediate signal may include a pseudo-random key signal so as to obscure the encoding and require knowledge of a corresponding key at the decoder to extract the auxiliary data from the encoded content. In some embodiments, calibration data is encoded in the content signal with the auxiliary data. This calibration data desirably has known properties (e.g., spectral attributes, data content, etc.) facilitating its identification in the encoded content signal.
    Type: Grant
    Filed: May 31, 2001
    Date of Patent: January 6, 2004
    Assignee: Digimarc Corporation
    Inventor: Geoffrey B. Rhoads
  • Patent number: 6674861
    Abstract: A method, an apparatus and a computer program product for adaptive, content-based watermark embedding of a digital audio signal (100) are disclosed. Corresponding watermark extracting techniques are also disclosed. Watermark information (102) is encrypted (120) using an audio digest signal, i.e. a watermark key (108). To optimally balance inaudibility and robustness when embedding and extracting watermarks (450), the original audio signal (100) is divided into fixed-length frames (1100, 1120, 1130) in the time domain. Echoes (S′[n], S″[n]) are embedded in the original audio signal (100) to represent the watermark (450). The watermark (450) is generated by delaying and scaling the original audio signal (100) and embedding it in the audio signal (100). An embedding scheme (104) is designed for each frame (1100, 1120, 1130) according to its properties in the frequency domain.
    Type: Grant
    Filed: December 2, 1999
    Date of Patent: January 6, 2004
    Assignee: Kent Ridge Digital Labs
    Inventors: Changsheng Xu, Jiankang Wu, Qibin Sun, Kai Xin, Haizhou Li
  • Patent number: 6654480
    Abstract: A consumer audio device decodes auxiliary control data that is hidden in audio information. The auxiliary control information can be used to trigger some response in the device, such as enabling or disabling certain operations.
    Type: Grant
    Filed: March 25, 2002
    Date of Patent: November 25, 2003
    Assignee: Digimarc Corporation
    Inventor: Geoffrey B. Rhoads
  • Patent number: 6628802
    Abstract: The present invention provides methods and apparatus that reverse the notion of the attack process in using intentional image distortion techniques as a means of indelibly marking an original image. It also provides for imparting and removing intentional image distortion to further obscure an embedded invisible watermark. It further provides means for hiding a watermark embedded into a watermarked image. It also provides for imparting distortion on an reference image to form a single level or multilevel caricature of the entire (or part of) the reference image.
    Type: Grant
    Filed: January 28, 2000
    Date of Patent: September 30, 2003
    Assignee: International Business Machines Corporation
    Inventors: Gordon Wesley Braudaway, Louis Paul Herzberg