Prior art — US Patent 8830293

Here is an analysis of the prior art cited in US patent 8830293, "Video superposition for continuous presence":

Most Relevant Prior Art for US8830293B2

Based on a review of the cited patents and the detailed description of US8830293B2, the most relevant prior art appears to be US20090033737A1, titled "Method and System for Video Conferencing in a Virtual Environment." This reference directly addresses video conferencing and the creation of virtual scenes, which closely aligns with the core inventive concept of superimposing video streams to achieve continuous presence in a life-like manner, particularly through background manipulation and combining subject images onto a shared display.

Analysis of Patent Citations for US8830293B2

Below is an overview of each patent cited by US8830293B2, including its full citation, publication/filing date, a brief description, and which claim(s) it potentially anticipates under 35 U.S.C. § 102.

1. US5572248A

Full Citation: US5572248A, Teleport Corporation, "Teleconferencing method and system for providing face-to-face, non-animated teleconference environment"
Publication/Filing Date: Publication Date: 1996-11-05; Priority Date: 1994-09-19
Brief Description: This patent describes a teleconferencing method and system aimed at providing a realistic "face-to-face" experience in a non-animated environment. It likely focuses on fundamental aspects of video conferencing, such as capturing and transmitting video and audio to simulate a meeting.
Potential Anticipation: While generally related to video teleconferencing, this patent, due to its older date, is unlikely to explicitly disclose the specific "combining" steps of US8830293B2 Claim 1, such as scaling, repositioning, removing backgrounds, or superimposing subject images in anterior and posterior portions to create an illusion of depth with near life-size images. It would primarily anticipate general aspects of "receiving at least first and second real-time video streams" and "supplying the combined video stream to a video display" in a teleconferencing context.

2. WO2001037559A1

Full Citation: WO2001037559A1, Telia Ab, "Procedure and arrangement at video conference system"
Publication/Filing Date: Publication Date: 2001-05-25; Priority Date: 1999-11-19
Brief Description: This international publication pertains to a general "procedure and arrangement" within a video conference system. The title suggests a focus on the operational aspects or system architecture of video conferencing.
Potential Anticipation: Similar to US5572248A, this reference is broadly related to video conferencing systems. However, its general title does not suggest the specific technical details of video superposition, background manipulation, and depth-of-field simulation described in US8830293B2. It might anticipate the broad concept of a video conference system, but not the detailed method of combining video frames as claimed in Claim 1, Claim 3, or Claim 5.

3. US20080048975A1

Full Citation: US20080048975A1, Michael Leibow, "Apparatus and System for Managing Multiple Computers"
Publication/Filing Date: Publication Date: 2008-02-28; Priority Date: 2005-04-12
Brief Description: This patent application describes an apparatus and system primarily for managing multiple computers. The technical domain appears distinct from real-time video stream processing for teleconferencing.
Potential Anticipation: This reference is unlikely to anticipate any claims of US8830293B2, as its subject matter focuses on managing multiple computers rather than video processing or teleconferencing techniques. It would not disclose elements like receiving real-time video streams, combining subject images, or generating a continuous presence display.

4. US20080095470A1

Full Citation: US20080095470A1, Hui Chao, "Digital Image Auto-Resizing"
Publication/Filing Date: Publication Date: 2008-04-24; Priority Date: 2006-10-23
Brief Description: This patent application focuses on the technical area of digital image auto-resizing. This involves methods and systems for automatically adjusting the size of digital images.
Potential Anticipation: This reference is relevant to the "scaling the video frames" step present in US8830293B2 Claim 1 (sub-step of combining), Claim 3 (sub-step of combining), Claim 10 (apparatus), Claim 13 (logic), and Claim 15 (logic). While it may disclose methods for scaling images, it is highly improbable that it also discloses the entire combination of steps required for anticipation, such as repositioning, background removal, superimposing, and the anterior/posterior arrangement of multiple real-time subject images for continuous presence in a teleconference. Therefore, it is unlikely to anticipate a full claim under 35 U.S.C. § 102 but is strong prior art for the specific sub-element of scaling.

5. US20090033737A1

Full Citation: US20090033737A1, Stuart Goose, "Method and System for Video Conferencing in a Virtual Environment"
Publication/Filing Date: Publication Date: 2009-02-05; Priority Date: 2007-08-02
Brief Description: This patent application describes a method and system for video conferencing within a virtual environment. This typically involves separating participants from their actual backgrounds and integrating their images into a shared, generated virtual space, often to simulate a shared meeting room or scene.
Potential Anticipation: This is the most relevant prior art.
- Claim 1: This reference has a strong potential to anticipate many elements of Claim 1, including "receiving at least first and second real-time video streams" (common in video conferencing), "each ... comprising video frames containing a picture comprising a subject image and a background image," "combining the subject images... into a combined frame... such that the subject image of the first video stream is positioned in an anterior portion... and the subject image of the second video stream is positioned in a posterior portion" (a virtual environment could readily facilitate such spatial arrangement), "scaling the video frames of the first video stream and repositioning in a first direction" (common in virtual scene composition), and "removing the background image" (essential for placing subjects into a virtual environment). The specific superimposition onto "corresponding ones of the video frames of the second video stream" (i.e., using the second stream's background, possibly extended) might be a distinguishing detail, but the general principle of background removal and superimposition within a combined visual space is highly likely disclosed.
- Claim 3: This claim introduces "extending the background image in the second sequence of scaled video frames." While virtual environments typically use a generated background, the concept of modifying a background for the posterior portion might be a distinguishing feature if US20090033737A1 primarily relies on entirely replacing backgrounds rather than extending existing ones.
- Claim 5: This claim, which describes "removing the background image in the video frames of the first and second video streams," "generating supplemental background image video frames," and "superimposing corresponding ones of the first background separated video frames and the second background separated video frames onto corresponding ones of the supplemental background video frames," aligns very strongly with the concept of creating a "virtual environment" for video conferencing. Placing background-separated participants onto a "supplemental background image" is a hallmark of virtual environment systems. Therefore, US20090033737A1 potentially anticipates Claim 5 directly.