Prior art — US Patent 8868772B2

Based on a review of the patent's file wrapper and citations, the following prior art references are most relevant to US Patent 8,868,772 B2. This analysis focuses on references cited during the patent's prosecution and listed on the issued patent, as these were considered by the USPTO examiner.

Analysis of Prior Art for US Patent 8,868,772 B2

The following prior art references were cited by the examiner or the applicant during the prosecution of the patent. The analysis considers their potential to anticipate the claims of US 8,868,772 B2, with a focus on independent claim 1.

1. US Patent 7,765,312 B2

Full Citation: US Patent 7,765,312 B2, "Method and system for providing media data to a client over a computer network," assigned to Microsoft Corporation.
Publication Date: July 27, 2010 (Filed: June 24, 2002).
Brief Description: This patent describes a system for streaming media content by dividing it into smaller pieces. A client device requests these pieces from a server. The system can switch between different bit rates for the media stream based on network conditions. It explicitly discloses using standard HTTP over TCP/IP to deliver the media pieces, which can be served from standard web servers.
Potential Anticipation of Claims: This reference appears to be highly relevant and potentially anticipates the core elements of Claim 1.
- "streaming by a media player...a video from a set of alternative video streams": The '312 patent describes providing media data from different bit rate streams (Column 2, lines 5-15).
- "each video stream comprising a plurality of streamlets": The '312 patent refers to these as "pieces" of the media stream (Abstract).
- "requesting...at least one streamlet from one of a plurality of web servers": It discloses a client requesting these pieces from a server using HTTP (Column 4, lines 45-55).
- "monitoring a performance factor related to receiving the at least one streamlet": The client in the '312 patent monitors network conditions to determine if a bit rate switch is necessary (Column 5, lines 20-30).
- "requesting a subsequent streamlet from a higher quality one...or a lower quality one...based on the performance factor": The '312 patent explicitly details a process for switching to a higher or lower bit rate stream based on monitored network performance (Column 5, lines 31-45).

2. US Patent 6,988,136 B2

Full Citation: US Patent 6,988,136 B2, "System and method for adaptively streaming and playing back media-content," assigned to RealNetworks, Inc.
Publication Date: January 17, 2006 (Filed: May 16, 2001).
Brief Description: This patent discloses a system where a media file is encoded at multiple bit rates. A client player monitors network bandwidth and buffer conditions. Based on this monitoring, the client can request that the server switch to a different, more appropriate bit rate stream to ensure smooth playback without interruption.
Potential Anticipation of Claims: This reference is also highly relevant and potentially anticipates key aspects of Claim 1.
- "streaming by a media player...from a set of alternative video streams": The '136 patent describes encoding content at multiple bit rates (Abstract).
- "monitoring a performance factor": The client player monitors buffer fullness and available bandwidth (Column 7, lines 1-10).
- "requesting a subsequent streamlet from a higher quality one...or a lower quality one": The system decides to "upshift" or "downshift" to a different bit rate stream based on the monitored conditions (Column 8, lines 15-25). The concept of discrete "streamlets" is less explicit than in the '772 patent but is functionally similar to the chunks of data requested from the different streams.

3. US Patent Application Publication 2002/0188733 A1

Full Citation: US 2002/0188733 A1, "System and method for providing uninterrupted playback of streaming media," authored by Poulose et al.
Publication Date: December 12, 2002 (Filed: June 6, 2001).
Brief Description: This application describes a client-side method for adaptive streaming. The client monitors the data arrival rate and its own buffer level. If the buffer level drops below a certain threshold, indicating network congestion, the client requests a lower bit rate version of the stream from the server. Conversely, if the buffer is sufficiently full and network conditions appear favorable, it can request a higher bit rate stream.
Potential Anticipation of Claims: This publication discloses the core feedback loop central to Claim 1.
- "monitoring a performance factor": The client monitors the rate of data arrival and the state of its playback buffer (Paragraph).
- "requesting a subsequent streamlet from a higher quality one...or a lower quality one": Based on the monitored factors, the client explicitly requests a stream with a different (higher or lower) bit rate from the server (Paragraph). This aligns directly with the adaptive shifting described in claim 1.

4. US Patent Application Publication 2004/0073693 A1

Full Citation: US 2004/0073693 A1, "Adaptive streaming of multimedia data from a server to a client," authored by Wei et al.
Publication Date: April 15, 2004 (Filed: October 10, 2002).
Brief Description: This application describes a client-driven adaptive streaming system. The media content is available in versions with different bit rates, each divided into segments. The client requests segments and measures the download time. Based on this measurement, it predicts the available bandwidth and determines which bit rate version of the next segment to request, allowing it to adapt to network fluctuations.
Potential Anticipation of Claims: This publication also describes the essential features of Claim 1.
- "each video stream comprising a plurality of streamlets": The application refers to these as "segments" (Paragraph).
- "monitoring a performance factor": The client measures the time it takes to download a segment to estimate bandwidth (Paragraph).
- "requesting a subsequent streamlet from a higher quality one...or a lower quality one...based on the performance factor": The client uses the bandwidth estimation to select the appropriate bit rate for the next segment to be requested (Paragraph).

Conclusion on Anticipation

The core concept of US 8,868,772 B2—a client-side media player adaptively requesting chunks of video from different quality streams based on monitored network performance—is well-described in prior art that predates its 2004 priority date. References such as US 7,765,312 B2 (filed 2002), US 6,988,136 B2 (filed 2001), and US 2002/0188733 A1 (filed 2001) all teach this fundamental process. The novelty of the '772 patent during examination was likely argued based on specific implementation details, such as the concept of "virtual pipelining" using multiple TCP connections for parallel retrieval of streamlet parts, as described in the detailed description (Column 8, lines 26-44). However, based purely on the text of independent claim 1, a strong argument for anticipation under 35 U.S.C. § 102 exists from multiple prior art references, particularly US 7,765,312 B2 and US 2002/0188733 A1.