Rate-distortion optimized video streaming with multiple deadlines

Abstract

We extend a recently-proposed framework for the rate-distortion optimized transmission of packetized media. The original framework assumed that each packet has a single arrival deadline and that a packet is useless if it arrives after its deadline. In practice, however, packets may be associated with multiple deadlines. Examples include the case of compressed video that uses bi-directional prediction and the case of decoders that can recover from late packet arrivals through the accelerated retroactive decoding of the dependency chain. We extend the original framework to consider multiple deadlines. In our experimental results for the case of the accelerated retroactive decoding of late packets, the multiple-deadline formulation yields up to a 1.5 dB improvement in rate-distortion performance compared to the original, singledeadline formulation. The results indicate, furthermore, that accelerated retroactive decoding offers significant benefit only when coupled with a scheduler that considers multiple deadlines.

Video-aware opportunistic network coding over wireless networks

“…Packet scheduling is an important control at the medium access control layer. The problem of ratedistortion optimized packet scheduling has been studied in the RaDiO family of techniques [9]- [12]: in every transmission opportunity, media units are selected for transmission so as to maximize the expected quality of received video subject to a constraint in the transmission rate, and taking into account transmission errors, delays and decoding dependencies.…”

“…The fact that video packets have unequal importance is well understood and extensively studied in the video streaming community, e.g. for rate-distortion optimized streaming [9]- [12]. The fact that mixing different information flows can increase throughput in multicast networks is well understood in the network coding community [3], [4], [13], [14].…”

Deadline-aware video delivery in a disrupted bluetooth network

“…There exist two deadline types for encoded video: 1) a display deadline, herein set by the playout buffer size; and 2) a decode deadline relative to the duration of a Group of Pictures (GOP). Packets forming an anchor frame (I-and P-picture) are still of value in retroactive decoding of subsequent P-or B-pictures [7]. However, if disruption is prolonged retained packets contribute to increasing buffer fullness, which may lead to excessive delay and, in severe cases, to send buffer overflow.…”

Congestion-Optimized Scheduling of Video over Wireless AD HOC Networks

“…The expected value of the distortion for the video stream decoded by the client is computed as in [10]. Namely, if copy error concealment is used, an undecodable frame is replaced with the nearest correctly decoded frame for display.…”

“…(4), P r{s} represents the probability that frame s is displayed instead of f . This probability may be computed, as described in [10], by combining the probabilities that different packets do not reach the client by their playout deadline. The difficulty resides in estimating the delay distribution function needed to derive these quantities.…”