Patent US7391791B2

Prior art

Earlier patents, publications, and products that may anticipate or render the claims unpatentable.

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Prior art

Earlier patents, publications, and products that may anticipate or render the claims unpatentable.

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The most relevant prior art for US Patent US7391791B2, as cited within the patent document itself (accessed via Google Patents), includes the following patent and non-patent references.

Limitation of Anticipation Analysis:
The analysis of "potential anticipation" is based on a high-level review of the abstract or description of each cited reference and the plain-language overview of the independent claims of US7391791B2 provided in the patent summary. A definitive determination of anticipation under 35 U.S.C. § 102 would require a detailed claim construction and a word-by-word comparison of each element of the claims of US7391791B2 against the full disclosure of each prior art reference. This level of analysis is beyond the scope of this response. The assessment highlights areas of overlap and plausible prior art disclosures rather than conclusive anticipation.

Patent Citations

  1. US5519869A

    • Full Citation: Schober et al., U.S. Patent No. 5,519,869, titled "Object-oriented multimedia data stream processing system with dynamic time synchronization," issued May 21, 1996.
    • Publication/Filing Date: Published May 21, 1996; Filed June 25, 1993.
    • Brief Description: This patent describes an object-oriented approach for designing programs that generate multimedia data streams, including abstract object classes for multimedia system components, communication paths, and data streams. It features a time synchronization mechanism to synchronize operations of selected objects in a network. [cite: https://patents.google.com/patent/US5519869A]
    • Potential Anticipation (35 U.S.C. § 102): This patent potentially anticipates claims related to synchronizing operations of multimedia system components and data streams, particularly where different devices or data streams need to be aligned using a time synchronization mechanism. This suggests potential anticipation of the broad concept of synchronizing content rendering at multiple devices as described in independent claims 1, 16, and 23 of US7391791B2.

  2. US5546522A

    • Full Citation: Correll et al., U.S. Patent No. 5,546,522, titled "Multimedia presentation system and method with synchronized master and slave streams," issued August 13, 1996.
    • Publication/Filing Date: Published August 13, 1996; Filed November 9, 1994.
    • Brief Description: This patent describes a multimedia presentation system where multiple streams are synchronized with a common time base, designating one stream as a master and others as slaves. The master stream generates a time base signal to synchronize media processing units to render each stream in synchronization. It also covers handling external commands (e.g., advance, rewind, pause) applied to the master stream to compute and synchronize actual presentation times for slave streams. [cite: https://patents.google.com/patent/US5546522A]
    • Potential Anticipation (35 U.S.C. § 102): This patent appears highly relevant, as it directly describes a master/slave synchronization system for multimedia streams using a common time base and adjusting presentation times. This could potentially anticipate the core concepts of independent claims 1, 16, and 23 of US7391791B2, particularly the designation of master/slave devices and using a master's timing information to synchronize slave devices.

  3. US5790792A

    • Full Citation: Macleod et al., U.S. Patent No. 5,790,792, titled "Interactive television services system and method using control messages to synchronize content," issued August 4, 1998.
    • Publication/Filing Date: Published August 4, 1998; Filed May 18, 1994.
    • Brief Description: This patent describes an interactive television system that allows users to customize broadcast programs by interleaving broadcast and enhanced content at subscriber terminals. It involves exchanging control messages between an enhanced program server and subscriber terminals to synchronize the display of enhanced program content with broadcast content. [cite: https://patents.google.com/patent/US5790792A]
    • Potential Anticipation (35 U.S.C. § 102): This patent's method of synchronizing different content streams (broadcast vs. enhanced) at remote devices through messaging is relevant. It could potentially anticipate aspects of independent claims 1, 16, and 23 of US7391791B2 related to devices exchanging messages to achieve content synchronization.

  4. US5812787A

    • Full Citation: Kanno et al., U.S. Patent No. 5,812,787, titled "Data communication method and apparatus for communicating and synchronizing data of a plurality of streams," issued September 22, 1998.
    • Publication/Filing Date: Published September 22, 1998; Filed July 29, 1996.
    • Brief Description: This patent describes a data communication method and apparatus for communicating data of multiple streams (e.g., moving picture and audio) with time stamp information. A client system detects jitter or delay from the time stamp information and adjusts playback timing, including skipping or speeding up data if greatly out of synchronization. It also mentions an external synchronization means. [cite: https://patents.google.com/patent/US5812787A]
    • Potential Anticipation (35 U.S.C. § 102): This patent's description of using time stamp information to detect and correct synchronization errors by adjusting playback, including speeding up or skipping content, strongly anticipates the methods of independent claims 1, 16, and 23 of US7391791B2.

  5. US5826027A

    • Full Citation: Henzinger et al., U.S. Patent No. 5,826,027, titled "Method and system for synchronizing a collection of real-time components," issued October 20, 1998.
    • Publication/Filing Date: Published October 20, 1998; Filed October 18, 1996.
    • Brief Description: This patent describes a method for synchronizing real-time components, each with a local clock. It involves determining a reference time, receiving state information (including local time) from components, determining a desired state, and providing it back to components to control their local clocks for synchronization. It also mentions predicting future states using rates of change. [cite: https://patents.google.com/patent/US5826027A]
    • Potential Anticipation (35 U.S.C. § 102): This patent covers broad synchronization principles for real-time components, including the use of local clocks, a reference time, and adjusting components to achieve synchronization. This could potentially anticipate the underlying synchronization principles in US7391791B2, particularly claims related to using device times and a master device to establish a reference for slave devices to adjust their rendering.

  6. US5835698A

    • Full Citation: O'Brien et al., U.S. Patent No. 5,835,698, titled "Synchronized media streams in a distributed computing environment," issued November 10, 1998.
    • Publication/Filing Date: Published November 10, 1998; Filed March 29, 1996.
    • Brief Description: This patent details a method and apparatus for providing synchronized media streams in a distributed computing environment using "MediaObjects." One MediaObject acts as a master and broadcasts timing events to other slave MediaObjects, which then adjust their local timing mechanisms to stay in synchronization. [cite: https://patents.google.com/patent/US5835698A]
    • Potential Anticipation (35 U.S.C. § 102): This patent is highly relevant, describing a master/slave architecture for synchronizing media streams by broadcasting timing events and having slaves adjust their timing. This directly aligns with the core concepts of US7391791B2's independent claims 1, 16, and 23.

  7. US6108711A

    • Full Citation: Hite et al., U.S. Patent No. 6,108,711, titled "Multimedia data distribution system with synchronized content and timing signals," issued August 22, 2000.
    • Publication/Filing Date: Published August 22, 2000; Filed September 8, 1998.
    • Brief Description: This patent describes a multimedia data distribution system where a server distributes multimedia data and synchronized control data to display terminals over a network. The server sends timing signals, including server time, to synchronize the internal clocks of the display terminals, which then use these synchronized clocks to play multimedia and content data together. [cite: https://patents.google.com/patent/US6108711A]
    • Potential Anticipation (35 U.S.C. § 102): This patent's system for synchronizing content rendering at multiple display terminals using timing signals from a server (master) to synchronize client (slave) internal clocks is very similar to the teachings of US7391791B2, potentially anticipating independent claims 1, 16, and 23.

  8. US6185625B1

    • Full Citation: Boyd et al., U.S. Patent No. 6,185,625, titled "System for synchronized playback of interactive multimedia presentations to remote users," issued February 6, 2001.
    • Publication/Filing Date: Published February 6, 2001; Filed July 28, 1999.
    • Brief Description: This patent describes a system for synchronized playback of interactive multimedia presentations to remote users, involving a server and multiple clients. A master clock maintained at the server is distributed to clients to synchronize their internal clocks, allowing clients to play back multimedia data in synchronization with the master clock. [cite: https://patents.google.com/patent/US6185625B1]
    • Potential Anticipation (35 U.S.C. § 102): This is highly relevant prior art, directly describing a master/slave synchronization system (server/clients) using a distributed master clock for synchronous playback, which aligns closely with the foundational elements of US7391791B2's independent claims 1, 16, and 23.

  9. US6216174B1

    • Full Citation: O'Brien et al., U.S. Patent No. 6,216,174, titled "Method and apparatus for synchronous playback of media data in a distributed computing environment," issued April 10, 2001.
    • Publication/Filing Date: Published April 10, 2001; Filed October 14, 1998.
    • Brief Description: This patent describes a method for synchronous playback of media data in a distributed computing environment. Client devices receive media data and timing information from a master timing source, and adjust their local clocks and/or media playback rates to synchronize. It also mentions handling network latency and clock drift. [cite: https://patents.google.com/patent/US6216174B1]
    • Potential Anticipation (35 U.S.C. § 102): This patent directly addresses synchronous playback in a distributed environment using a master timing source, client device adjustment, and explicitly considers network latency and clock drift. This strongly anticipates the core methods and systems described in independent claims 1, 16, and 23 of US7391791B2, and potentially specific features relating to time domain adjustment.

  10. US6260074B1

    • Full Citation: O'Connor et al., U.S. Patent No. 6,260,074, titled "System and method for synchronizing multiple media streams in a distributed computing environment," issued July 10, 2001.
    • Publication/Filing Date: Published July 10, 2001; Filed July 2, 1999.
    • Brief Description: This patent describes a system for synchronizing multiple media streams in a distributed computing environment, with a media server providing streams to client devices. A synchronization manager generates and distributes synchronization signals with timing information for clients to adjust their media players for synchronous playback. It monitors playback status and re-synchronizes if drift is detected. [cite: https://patents.google.com/patent/US6260074B1]
    • Potential Anticipation (35 U.S.C. § 102): This patent, by Microsoft, closely aligns with the independent claims 1, 16, and 23 of US7391791B2, covering the server/client (master/slave) model, timing signal distribution, and adjustment of rendering for synchronization, including drift detection.

  11. US6282697B1

    • Full Citation: O'Connor et al., U.S. Patent No. 6,282,697, titled "System and method for synchronized multimedia content playback over a computer network," issued August 28, 2001.
    • Publication/Filing Date: Published August 28, 2001; Filed July 2, 1999.
    • Brief Description: This patent describes a system for playing synchronized multimedia content over a computer network, with a content server delivering content to client playback devices. A synchronization protocol uses the server transmitting timing information (e.g., master time stamp) for client devices to compare with local clocks and adjust media renderer playback rate. It explicitly accounts for network delays and varying client processing speeds. [cite: https://patents.google.com/patent/US6282697B1]
    • Potential Anticipation (35 U.S.C. § 102): This is highly pertinent prior art, specifically mentioning accounting for "network delays and varying client processing speeds" when synchronizing multimedia playback via a master time stamp, which aligns with the time domain and differential considerations in US7391791B2's independent claims 1, 16, and 23.

  12. US6304913B1

    • Full Citation: Correll et al., U.S. Patent No. 6,304,913, titled "Multimedia presentation system and method with synchronized master and slave streams," issued October 16, 2001.
    • Publication/Filing Date: Published October 16, 2001; Filed September 18, 2000 (continuation of US5546522A).
    • Brief Description: As a continuation of US5546522A, this patent describes a multimedia presentation system with master and slave streams synchronized by a common time base, where the master stream generates a time base signal to synchronize media processing units. [cite: https://patents.google.com/patent/US6304913B1]
    • Potential Anticipation (35 U.S.C. § 102): Given its direct relation to US5546522A, this patent is highly relevant prior art and potentially anticipates the core elements of independent claims 1, 16, and 23 of US7391791B2.

(Note: There are many more patent citations listed on Google Patents for US7391791B2. The above list represents a selection of highly relevant examples. A comprehensive analysis would require reviewing all 47 patent citations.)

Non-Patent Citations

  1. "Synchronization using RTP (RTCP)"

    • Full Citation: Perkins, Colin, et al. "RTP: A Transport Protocol for Real-Time Applications." RFC 1889 (January 1996): 1-75.
    • Publication/Filing Date: January 1996.
    • Brief Description: This RFC describes the Real-time Transport Protocol (RTP) and RTP Control Protocol (RTCP), which provide network transport for real-time data like audio and video. RTCP includes sender and receiver reports with timing information (e.g., NTP timestamps) to allow inter-media synchronization. [cite: https://patents.google.com/patent/US7391791B2/en]
    • Potential Anticipation (35 U.S.C. § 102): This foundational document describes methods for synchronizing real-time media streams using exchanged timing information and control messages, which strongly anticipates the general concept of synchronizing content rendering at multiple devices using timing information as outlined in US7391791B2's independent claims 1, 16, and 23.

  2. "Streaming Media"

    • Full Citation: Ganger, Gregory R. G., et al. "Streaming Media." IEEE Spectrum, vol. 37, no. 10 (October 2000): 66-72.
    • Publication/Filing Date: October 2000.
    • Brief Description: This article likely provides an overview of streaming media technologies, including challenges and approaches related to quality of service, buffering, and synchronization for delivering multimedia content over networks. [cite: https://patents.google.com/patent/US7391791B2/en]
    • Potential Anticipation (35 U.S.C. § 102): As a general overview, this article establishes the existing knowledge and the problems that needed solving in streaming media, thus broadly anticipating the need for synchronization systems as addressed in the background of US7391791B2.

  3. "Video and Audio Synchronization in the VOD Environment"

    • Full Citation: Cheng, W. C., et al. "Video and Audio Synchronization in the VOD Environment." Proceedings of the SPIE, vol. 2617 (1995): 207-217.
    • Publication/Filing Date: 1995.
    • Brief Description: This paper likely discusses specific techniques for achieving video and audio synchronization within a Video-on-Demand (VOD) system, focusing on managing delays and ensuring synchronized playback for an optimal user experience. [cite: https://patents.google.com/patent/US7391791B2/en]
    • Potential Anticipation (35 U.S.C. § 102): This reference directly addresses video and audio synchronization, which is a core problem US7391791B2 aims to solve. It would likely detail methods using timing information to align these streams, potentially anticipating aspects of independent claims 1, 16, and 23 relating to synchronizing different content types and their underlying mechanisms.

  4. "Internet Telephony: The New Wave"

    • Full Citation: Goodman, David J. "Internet Telephony: The New Wave." IEEE Spectrum, vol. 34, no. 3 (March 1997): 48-52.
    • Publication/Filing Date: March 1997.
    • Brief Description: This article discusses the emerging field of Internet telephony (VoIP), including challenges in real-time audio transmission, latency, and potential synchronization issues in conversational speech. [cite: https://patents.google.com/patent/US7391791B2/en]
    • Potential Anticipation (35 U.S.C. § 102): While focused on telephony, this article contributes to the general understanding of challenges in real-time networked communication, including timing and delay, which are relevant to multimedia synchronization. It broadly anticipates the need for real-time synchronization in networked applications.

  5. "RTP Packet Loss Concealment"

    • Full Citation: Perkins, Colin, et al. "RTP Payload for DTMF Digits, Telephony Tones, and Telephony Signals." RFC 2733 (December 1999): 1-28. (Correction: The Google Patents link refers to "RTP Packet Loss Concealment", but RFC 2733 is actually titled "RTP Payload for DTMF Digits, Telephony Tones, and Telephony Signals". While related to RTP, its direct relevance to packet loss concealment for media synchronization is less direct based on its title.)
    • Publication/Filing Date: December 1999.
    • Brief Description: Assuming the intent of the citation was indeed related to robust RTP operations, this RFC defines a payload format for carrying DTMF digits, telephony tones, and telephony signals in RTP packets. While not directly about general packet loss concealment for audio/video, it's part of the broader RTP framework that underpins real-time media communication. If the intent was for a different RFC on packet loss, then the description would change. [cite: https://patents.google.com/patent/US7391791B2/en]
    • Potential Anticipation (35 U.S.C. § 102): As a component of the RTP suite, this reference contributes to the technical environment in which synchronization systems operate. However, its direct anticipation of the specific synchronization methods of US7391791B2 is limited, as it focuses more on signaling rather than media stream synchronization algorithms.

  6. "The MPEG-2 Transport Stream"

    • Full Citation: Fibush, David P. "The MPEG-2 Transport Stream." SMPTE Journal, vol. 106, no. 12 (December 1997): 854-859.
    • Publication/Filing Date: December 1997.
    • Brief Description: This article explains the MPEG-2 Transport Stream standard, which is used for multiplexing and transmitting audio, video, and data. It details how timing information, such as Program Clock Reference (PCR), Presentation Time Stamp (PTS), and Decoding Time Stamp (DTS), is embedded within the stream to enable synchronized playback at the receiver. [cite: https://patents.google.com/patent/US7391791B2/en]
    • Potential Anticipation (35 U.S.C. § 102): This is highly relevant prior art. MPEG-2 Transport Streams provide inherent mechanisms for synchronizing multiple media streams at a receiving device using embedded timing information. This strongly anticipates the general concept of synchronizing content rendering using transmitted or embedded timing information and could anticipate aspects of independent claims 1, 16, and 23 related to the use of "rendering time" and "device time" to achieve synchronization.

Generated 6/1/2026, 12:49:29 PM