Cisco Technology, Inc.

Deutschetelekom Ag

Ashish Khisti

John George Apostolopoulos

Xiaoqing Zhu

Dan Tan

Ahmed Badr

Wai-Tian Tan

Ahmed Atef Younes Badr

Michael Anthony Ramalho

Jatinder Pal Singh

In various implementations, a method includes determining a sequence of source packets. In some implementations, the sequence of source packets satisfies a windowing condition. In various implementations, the method includes synthesizing a first set of one or more parity packets as a function of a first set of source packets in the sequence. In some implementations, the first set of source packets satisfies a first encoding pattern. In various implementations, the method includes synthesizing a second set of parity packets as a function of a second set of source packets in the sequence. In some implementations, the second set of source packets satisfies a second encoding pattern that is different from the first encoding pattern. In some implementations, the first and second encoding patterns characterize an encoding structure determined as a function of a channel characterization vector.

Malleable error control code structures suitable for adaptive error protection

An endpoint device receives a sequence of audio frames. The endpoint device determines for each audio frame a respective importance level among possible importance levels ranging from a low importance level to a high importance level based on content in the audio frame indicative of the respective importance level. The endpoint device associates each audio frame with the respective importance level, to produce different subsets of audio frames associated with respective ones of different importance levels. The endpoint device, for each subset of audio frames, applies forward error correction to a fraction of audio frames in the subset of audio frames, wherein the fraction increases as the importance level of the audio frames in the subset increases, and does not apply forward error correction to remaining audio frames in the subset.

Audio frame labeling to achieve unequal error protection for audio frames of unequal importance

In one embodiment, a device in a network assigns packets from a communication transmitted via the network to time windows over a period of time. The device determines a transmission performance metric for each of the packets in a particular time window and calculates, for each of the time windows, local disturbance scores, which are based on the transmission performance metrics for the packet in the time windows. A particular local disturbance score for a particular time window maps the transmission performance metrics for the packets in the time window to a perceived quality metric. The device determines a distortion score for the communication by aggregating the local disturbance scores for the time windows over the period of time.

Content-independent evaluation of streaming media based on packet transmission performance

An encoder receives a sequence of packets. For each packet, the encoder selects a window of at least previous packets in the sequence of packets. The encoder identifies in the window one or more earlier packets among the previous packets and one or more later packets separated from the one or more earlier packets by a gap including gap packets. The encoder encodes the one or more earlier packets and the one or more later packets into a forward error correction (FEC) packet corresponding to the packet, without using any of the gap packets, and transmits the FEC packet and the packet.

Forward error correction for low-delay recovery from packet loss

In one embodiment, a device in a network identifies delay requirements of each of a plurality of media streams. The device selects a joint forward error correction (FEC) encoding strategy for the plurality of media streams based on the identified delay requirements of the streams and on a burst loss length of a communication channel. The device applies the selected joint FEC encoding strategy to the plurality of media streams, to form a multiplexed packet stream. The device sends the multiplexed packet stream to one or more nodes in the network via the communication channel.

Multiplexing FEC protection of multiple streams with different delay requirements

An error correction code includes a separate error code portion for each of two or more separate burst erasure durations (or burst error durations). For each burst erasure duration, the code can be employed to recover from the burst erasure with a different delay time. Each error code portion has a particular parameter for burst duration (B) and delay (T), meaning that the code can be used to recover from a burst erasure of duration B with delay T. Each error code portion is based on separating the source symbols into sub-symbols and diagonally interleaving the sub-symbols based on the (B,T) parameters for the error code portion. Accordingly, different burst erasures are recovered from with different delays.

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Toronto, Canada

Ashish Khisti