Variable Content Characteristic and Variable Network Coding for Wireless Digital Video Broadcasting Application

Digital video broadcasting network facilitates distribution of real time video and video on demand services to global end users. This network has significant limitations stemming from scarced network resources to meet users popular demand of improved received quality. This research, presents a thorough investigation of variable content characteristic and application of variable network coding on digital video quality performance over wireless channel to enhance received video quality performance. In the proposed scheme, variable channel coding-rate is deployed to provide significant received quality performance gain by intelligently avoiding waste of limited network resources related to the fixed resource allocation necessary to guarantee acceptable quality performance. In order to assess the performance of the proposed scheme, experimental set up consisting of H.264 reference software for source coding, motion rate classifier and simulated wireless channel consisting of various channel coding and modulation schemes were adopted for this study. The test video samples were classified into high and low motion rate videos. In contrast, investigation of extension from fixed channel coding scheme to the application of variable channel coding-rate and modulation schemes in response to variable content motion-rate is analyzed over error free and poor channel conditions. The quality performance of received video quality over various wireless channel conditions is measured using standard objective algorithm, Peak-Signal-to-Noise-Ratio (PSNR). For the Soccer test video sample representing high motion rate videos, the 16QAM;1/2, the lower channel coding rate recorded the highest received video quality performance with PSNR value of 37.95dB compared to PSNR values of 33.29dB for 64QAM;1/2, and 24.40dB for the 64QAM;2/3 modulation and channel coding technique. Whereas, Akiyo test video sample representing low motion rate videos recorded significant quality performance of 51.19dB, 50.97dB and 39.93dB for 16QAM;1/2, 64QAM;1/2 and 64QAM;2/3 channel coding and modulation schemes, respectively.