Patent ID: 8625589
Filing Date: 2014-01-07
Classification: H04L,H04N

Abstract:
1. An audio/video network comprising: a packet-switched network over which data including audio and/or video data packets can be carried; at least one data source connected to the network and operable to assemble packetised data comprising multiple respective audio/video data streams at a first resolution and at a second resolution greater than the first resolution, and to transmit data packets carrying said multiple audio/video streams at the first resolution by multicast network transmission; and at least one client connected to the network, being a data handling device for handling packetised audio/video data and being arranged to join a multicast group to receive the multiple audio/video streams at the first resolution, wherein the client is associated with a graphical user interface configured in conjunction with a processor to select an audio/video stream, the processor is arranged to issue a unicast command to cause transmission of the selected audio/video stream at the second resolution from the source to the client, and the client is configured to synchronize the alignment of frames upon switching of frames from a stream at said first resolution to frames of the selected stream at the said second resolution in accordance with delay information.