Rate Control for Gop-Level Rate Adaptation in H.264 Video Coding

It may be desirable to adapt the coding bitrate according to both bandwidth availability and user preferences in video transmission over packet networks. Classical approaches for rate adaptation has been bitstream switching, which requires storing several pre-coded versions of the same video at different bitrates, or layered (scalable) video coding, which has coding efficiency and/or complexity penalties. In this paper the authors propose a new GOP-level rate adaptation scheme for a single stream, variable target bitrate H.264 encoder, which allows each Group Of Pictures (GOP) to be encoded at a specified bitrate, using a dynamically updated table to select the starting quantization parameter for each GOP.