Efficient frame forwarding in large scale real-time screen content sharing meetings

摘要

Techniques are provided to improve user experience at endpoint devices that are participating in a multipoint screen content sharing session. A server in a multipoint communication system receives video frames from a sending endpoint device in the communication session that involves one or more other endpoint devices that are to receive video frames from the sending endpoint device. The video frames include key reference frames that use either intra-frame prediction or inter-frame prediction based only on other key reference frames. The server stores the key reference frames. When a new receiving endpoint device joins the communication session, the server sends all the stored key reference frames to the new receiving endpoint device. All video frames received from the sending endpoint device are forwarded to existing ordinary receiving endpoint devices. Key reference frames and some, but not all, non-key reference video frames are forwarded to existing low-capacity receiving endpoint devices.

主权项

1. A method comprising:
at a server in a multipoint content sharing system, receiving video frames from a sending endpoint device in a communication session that involves one or more other endpoint devices that are to receive video frames from the sending endpoint device, the video frames representing screen content at the sending endpoint device and including key reference frames, wherein the sending endpoint encodes a current key reference frame based on a comparison of a size of all currently encoded key reference frames to a threshold value; storing the key reference frames at the server; sending all the stored key reference frames to a new receiving endpoint device that joins the communication session; determining network conditions with respect to existing receiving endpoint devices and decoding capacity of existing receiving endpoint devices; classifying one or more existing receiving endpoint devices into a first group based on relatively poor network conditions or relatively low decoding capacity, or into a second group based on relatively good network conditions or relatively high decoding capacity; forwarding all video frames received from the sending endpoint device to the second group of existing receiving endpoint devices; and forwarding key reference frames and some, but not all, non-key reference video frames to the first group of existing receiving endpoint devices.