High resolution graphics side channel in video conference

Abstract

A videoconference system can automatically transmit first and second images from a local site to a remote site where the first image is a high-resolution live image and the second image may be transmitted either as a high-resolution live or still frame image. Two video streams representing the first and second images are transmitted together to the remote site within a single carrier channel. The second image is transmitted as a still image whenever the second image is static to conserve bandwidth.

1 - 49 . (canceled)  
   
   
       50 . A videoconferencing system comprising: 
 a first input for receiving a live video image signal;    a second input for receiving a sound signal;    a third input for receiving an alternate image source signal; and    a communications interface whereby the live video image, sound, and alternate image may be transmitted to a remote site through a carrier channel comprising a video subchannel and an audio subchannel;    wherein the videoconference system automatically allocates video subchannel bandwidth between the live video image, transmitted in a normal conference video stream, and the alternate image, transmitted in an alternate video stream.    
   
   
       51 . The videoconferencing system of  claim 50  wherein the second and third inputs are part of a videoconference accessory module.  
   
   
       52 . The videoconferencing system of  claim 50  wherein at least one of the live video image and the alternate image is transmitted in a high resolution format.  
   
   
       53 . The videoconferencing system of  claim 50  wherein the videoconference system automatically allocates video subchannel bandwidth between the live video image and the alternate image by transmitting a live image in the alternate video stream only when the alternate image is changing and, at all other times, when the alternate image is static, transmitting a static image in the alternate video stream.  
   
   
       54 . The videoconferencing system of  claim 52  wherein at least one of the live video image and the alternate image is transmitted in a high resolution format.  
   
   
       55 . The videoconferencing system of  claim 50  wherein the alternate image is derived from a source selected from the group consisting of a document camera and a personal computer.  
   
   
       56 . The videoconferencing system of  claim 55  wherein at least one of the live video image and the alternate image is transmitted in a high resolution format.  
   
   
       57 . The videoconferencing system of  claim 53  wherein the alternate image is derived from a source selected from the group consisting of a document camera and a personal computer.  
   
   
       58 . The videoconferencing system of  claim 57  wherein at least one of the live video image and the alternate image is transmitted in a high resolution format.  
   
   
       59 . A method of processing audio and video for a videoconference, the method comprising: 
 receiving from a first source a live video image signal;    receiving from a second source a sound signal;    receiving from a third source an alternate image signal;    transmitting the live video image, sound, and alternate image to a remote site through a carrier channel comprising a video subchannel and an audio subchannel; and    automatically allocating video subchannel bandwidth between the live video image, transmitted in a normal conference video stream, and the alternate image, transmitted in an alternate video stream.    
   
   
       60 . The method of  claim 59  wherein at least one of the live video image and the alternate image is transmitted in a high resolution format.  
   
   
       61 . The method of  claim 59  wherein automatically allocating video subchannel bandwidth further comprises: 
 transmitting a live image in the alternate video stream only when the alternate image is changing; and    transmitting a static image in the alternate video stream at all other times when the alternate image is static.    
   
   
       62 . The method of  claim 61  wherein at least one of the live video image and the alternate image is transmitted in a high resolution format.  
   
   
       63 . The method of  claim 59  wherein the third source is selected from the group consisting of a document camera and a personal computer.  
   
   
       64 . The method of  claim 63  wherein at least one of the live video image and the alternate image is transmitted in a high resolution format.  
   
   
       65 . The method of  claim 63  wherein the third source is selected from the group consisting of a document camera and a personal computer.  
   
   
       66 . The method of  claim 65  wherein at least one of the live video image and the alternate image is transmitted in a high resolution format.  
   
   
       67 . A videoconferencing system comprising: 
 a communications interface whereby a live video image, sound, and an alternate image may be received from a remote site;    a first output for delivering the live video image to a first display device; and    a second output for delivering the alternate image to a second display device;    wherein the alternate image is received through an alternate video stream that contains a live image only when the alternate image is changing and, at all other times, when the alternate image is static, contains a static image.    
   
   
       68 . The videoconferencing system of  claim 67  wherein at least one of the live video image and the alternate image are in a high resolution format.  
   
   
       69 . The videoconferencing system of  claim 67  wherein the first and second display devices are selected from the group consisting of: two separate monitors, a single monitor that can switch back and forth between channels, and a single monitor with multi-channel picture-in-picture capability.