| 摘要 |
The invention relates to a method of coding video data available in the form of a first input stream of video frames, and to a corresponding coding device. This method, implemented for instance in three successives stages (101, 102, 103), comprises the steps of (a) encoding said first input stream to produce a first coded base layer stream (BL1) suitable for a transmission at a first base layer bitrate ; (b) based on said first input stream and a decoded version of said encoded first base layer stream, generating a first set of residual frames in the form of a first enhancement layer stream and encoding said stream to produce a first coded enhancement layer stream (EL1) ; and (c) repeating at least once a similar process in order to produce further coded base layer streams (BL2, BL3,..) and further coded enhancement layer streams (EL2, EL3,..). The first input stream is thus, for obtaining a required spatial resolution, compressed by encoding the base layers up to said spatial resolution with a lower bitrate and allocating a higher bitrate to the last base layer and/or to the enhancement which corresponds to said required spatial resolution. A corresponding transmission method is also proposed. |
