Definition of the best strategy for buffer control of a multistream ultra low delay HDTV codec
Therefore, a parallelization technique, referred as multistream approach, where the input data is spatially partitioned before encoding, converting an HDTV sequence into multiple SDTV sequences, each of them being encoded in parallel to obtain multiple encoded bitstreams. The decoder consists of multiple decoding units that reconstruct the original SDTV sequences and a spatial joining unit that reverts the encoder partition schema giving the decoded HDTV sequence.
Furthermore, some video codec have specific targets that require them to work in real-time. This new constrain will affect mainly the rate buffer size due to its main contribution to total encoding delay. For a real-time operation, a low delay upper bound is fixed, which greatly reduces the rate buffer size making it much more sensible to bitrate changes and prone to overflow or underflow. In order to avoid overflowing and underflowing, a new rate control strategy, that takes into consideration the new codec environment and target, has been developed.
Virtual Memory support for MPEG-4 Accelerators on FPGA
Contact: Christophe Lucarz