Systems and methods for error resilience in video communication systems
AssigneeVidyo, Inc.
InventorsAlexandros Eleftheriadis, Stephen Cipolli, Jonathan Lennox
Life of this patent
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Abstract
Systems and methods for error resilient transmission and for random access in video communication systems are provided. The video communication systems are based on single-layer, scalable video, or simulcast video coding with temporal scalability, which may be used in video communication systems. A set of video frames or pictures in a video signal transmission is designated for reliable or guaranteed delivery to receivers using secure or high reliability links, or by retransmission techniques. The reliably-delivered video frames are used as reference pictures for resynchronization of receivers with the transmitted video signal after error incidence and for random access.
Claims17
A system for media communications between a transmitting endpoint or server and one or more receiving endpoint(s) or server(s) over a packet-based communication network, the system comprising:
- an encoder which encodes transmitted media as pictures in a threaded coding structure having a number of different layers including a lowest temporal layer, wherein each picture is associated with a picture index number
- wherein data corresponding to a single picture is portioned and transmitted in one or more individual data packets,
- wherein an individual data packet comprises data elements that indicate:
- for the lowest temporal level pictures, a sequence number identifying said pictures,
- for other temporal level pictures, a reference to the sequence number of the most recent, in decoding order, lowest temporal level picture, and
- for all pictures, a ‘start’ flag and an ‘end’ flag that respectively indicate if the individual data packet contains the first or last data portions of the picture,
- so that a receiving endpoint or server on receipt of the individual data packet can detect a loss of portions of a lowest temporal level picture by examining if all data portions of the picture corresponding to the referenced picture index have been received at the receiving endpoint or server such that their packet sequence numbers contain no gaps, and where the first such data portion has the ‘start’ bit set and the last such data portion has have the ‘end’ bit set.
A method for media communications between a transmitting endpoint or server and one or more receiving endpoint(s) or server(s) over a packet-based communication network, wherein an encoder encodes transmitted media as pictures in a threaded coding structure having a number of different layers including a lowest temporal layer, and wherein data corresponding to a single picture is portioned and transmitted in one or more individual data packets, the method comprising:
- placing in each individual data packet data elements that indicate:
- for the lowest temporal level pictures, a sequence or index number identifying said pictures,
- for other temporal level pictures, a reference to the sequence number of the most recent, in decoding order, lowest temporal level picture, and
- for all pictures, a ‘start’ flag and an ‘end’ flag that indicate if the individual data packet contains the first or last, respectively, data portions of the picture,
- so that a receiving endpoint or server on receipt of the individual data packet can detect a loss of portions of a lowest temporal level picture by examining if all data portions of the picture corresponding to the referenced picture index have been received at the receiving endpoint or server such that their packet sequence numbers contain no gaps, and where the first such data portion has the ‘start’ bit set and the last such data portion has the ‘end’ bit set.
Computer readable media comprising a set of instructions to perform the steps recited in at least one of the method claims 9-16.
Dependencies are inferred from the claim text.