Video Splicing and Fuzzy Rate Control in IP Multi-Protocol Encapsulator for Tune-In Time Reduction in IP Datacasting (IPDC) over DVB-H

摘要

A novel video splicing and rate control method is proposed which minimizes the tune-in time in IPDC over DVB-H. DVB-H uses a time-sliced transmission scheme to reduce the power consumption used for radio reception. One of the significant factors in tune-in time is the time from the start of media decoding to the start of correct output from decoding, which would be minimized when a time-slice is started with a random access point picture such as an instantaneous decoding refresh (IDR) picture in H.264/AVC. In IPDC over DVB-H, the encapsulation to time-slices is performed independently of encoding in a network element called IP encapsulator. At the time of encoding, time-slice boundaries are not known exactly, and it is impossible to govern the location of IDR pictures relative to time-slices. It is proposed that an additional stream consisting of IDR pictures only is transmitted to the IP encapsulator, which replaces pictures in a normal bitstream with IDR pictures according to time-slice boundaries in order to achieve the minimum tune-in time. It has to be ensured that the "spliced" bit stream resulting from the operation of the IP encapsulator complies with the hypothetical reference decoder (HRD) specification of H.264/AVC. A video rate control system utilizing a fuzzy controller is proposed to satisfy the HRD requirements for the spliced bit stream. Simulation results show that the proposed splicing method and rate control system can provide standard bit streams with good average quality of decoded video and with minimum tune-in time