Patent AU-2014202368-B2 (AU)
Title: Improved view layout management in scalable video and audio commununication systems
Inventor: ADRAGNA JAMES P
IPC: H04N11/02
Filed: 2014-04-30
Granted: 2016-04-14
Abstract: An audiovisual communication system for transmitting a plurality of video signals and associated audio signals, if any, over a communication network for presentation to one or more end users, wherein the video signals are scalably coded into layers including a base layer and one or more enhancement layers, the system comprising: a receiver configured to receive the plurality of video and any associated audio signals over the communication network, determine a layout for the displayed video signals based on a set of criteria, and communicate information about the determined layout; a display, connected to the receiver, configured to display one or more of the received video signals using the determined layout; and one or more servers, connected to the communication network, adapted to receive the information about the determined layout, and configured to transmit the plurality of video and any associated audio signals over the communication network; wherein the one or more servers are configured to selectively transmit, for each of the plurality of video signals, no layers, the base layer, or the base layer and one or more enhancement layers, if any, that are necessary for displaying the video signals in the determined layout; wherein the one or more servers are further configured to determine which of the audio signals to selectively transmit by using audio activity indicators for each of the associated audio signals and an indication of whether the associated video signal is displayed in the determined layout, such that audio signal data is transmitted for one or more of the audio signals with the highest activity and audio signal data associated with one or more of the video signals that are displayed in the determined layout is transmitted, and no audio signal data is transmitted associated with the remaining video signals; wherein the receiver is further configured to maintain for the determined layout the number of views N and the number of enlarged views P, where P ranges from 0 to N-1, as well as the total number M of video signals each having an associated audio signal, and wherein at certain time instances or upon a change in M, reassign views to the determined layout by: sorting the M video signals by decreasing associated audio activity into a list F; sequentially assign the first P video signals in F such that: if a video signal is already assigned an enlarged view it retains its current enlarged view, H:\mka\Interwoven\NRPortbl\DCC\MKA\6255962_1.DOC - 30/4/14 otherwise if a replacing video signal was assigned a standard view it is assigned the enlarged view that was assigned to the video signal with the smallest associated audio activity among the video signals that were previously assigned an enlarged view, and the video signal with the smallest associated audio activity among the video signals that was previously assigned an enlarged view is assigned the replacing video signal's original standard view, otherwise if a video signal was not previously assigned an enlarged or standard view it is assigned an enlarged view that was assigned to the video signal with the smallest associated audio activity among the video signals that were previously assigned an enlarged view, whereas the video signal with the smallest associated audio activity among the video signals that were previously assigned an enlarged view is inserted in a list G; sequentially assign the top max{N-P-IGI, 01 video signals in F to the next available free views in the current layout; sequentially assign the video signals in G to the remaining available free views in the current layout. H:\mka\Interwoven\NRPortbl\DCC\MKA\6255962_1.DOC - 30/4/14 WO 2009/152158 PCT/US2009/046758 FIG. 1: System Architecture NETWORK 102 RECEIVER STREAM 2 YE 3