An intelligent MPEG rate control in 2.4 GHz frequency

摘要

Transmitting Moving Picture Expert Group (MPEG) Variable Bit Rate (VBR) video stream over 2.4GHz wireless frequency demands a large bandwidth and may result in data loss and delay, because of excessive fluctuation in bit rate. Transmission over 2.4 GHz frequency further causes uncertainty due to interferences by other wireless devices in the same frequency band and/or common dynamic channel noises. As a result, an intelligent system has been developed for MPEG video transmission over 2.4GHz frequency band. A novel fuzzy controller automatically determines the quantization scale for each Group Of Picture (GOP) of the encoder during the transmission period. Moreover, a fuzzy controller and a neural-fuzzy controller stream the MPEG video data to conform to the current condition of dynamic wireless channel to maintain image quality during the transmission. In the intelligent system, rather than choosing the parameters associated with a given membership function arbitrarily, these parameters arc chosen as such to tailor the membership functions to the desired input/output data. The intelligent system computes and trains the system in such a way that its output will be equal to the desired value. Computer simulation results demonstrate that the proposed intelligent technique increases transmission rate and reduces data loss, excessive delay and image quality degradation as compared with a conventional video transmission over 2.4 GHz frequency band.