Method of transmitting a pre-coded video signal over a communication network

摘要

A video signal pre-coded using hierarchical coding is transmitted over a communication network, the signal being constituted by data distributed into several hierarchical levels. More specifically, a bandwidth of the communication network is periodically estimated over evaluation periods. A set of hierarchical levels is selected for a current evaluation period, where a transmission rate of the data of the selected hierarchical levels is compatible with the bandwidth estimated for a current evaluation period. A change tendency of the bandwidth is estimated for a following evaluation period. Additional data of the video signal to transmit is then determined depending on the estimated change tendency of the bandwidth, and the data of the selected hierarchical levels and the determined additional data is transmitted during the current evaluation period.

主权项

1. A transmission method for transmitting a video signal over a communication network, comprising the following steps:
pre-coding the video signal using hierarchical coding thereby obtaining pre-coded video signal, the pre-coded video signal being constituted by data distributed into a plurality of hierarchical levels; periodically estimating a bandwidth of the communication network over evaluation periods; selecting, for a current evaluation period, a set of hierarchical levels in the plurality of hierarchical levels constituting the pre-coded video signal, wherein a transmission rate of the data of the selected hierarchical levels is compatible with the bandwidth estimated for the current evaluation period; estimating a change tendency of the bandwidth for a following evaluation period; determining additional data of the video signal to transmit depending on the estimated change tendency of the bandwidth, wherein the additional data are chosen from among data of the current evaluation period or data of the following evaluation period, wherein if the bandwidth for the following evaluation period has a tendency to increase, the additional data are chosen in at least one hierarchical level higher than the set of hierarchical levels selected for the current evaluation period, and wherein if the bandwidth for the following evaluation period has a tendency to decrease, the additional data are chosen from among at least one hierarchical level of the following evaluation period, wherein the hierarchical level is identical to a hierarchical level of the set of hierarchical levels selected for the current evaluation period; and transmitting the data of the selected hierarchical levels and the determined additional data during the current evaluation period.