An Unequal Error Protection Scheme for HEVC Encoded Video Streams Over Wireless Fading Channels Using RCPC Codes

摘要

Digital video technology has evolved from VGA to UHD and 4K in last few decades. With recent advances in technology, HD and Ultra HD digital video content has become ubiquitous. Many of the latest digital multimedia devices like LED TV's, smartphones, tablets and portable media players are capable of streaming HD and UHD content over wireless mediums. The main challenges in transmitting HD and UHD video content over wireless mediums is that it requires high compression efficiency and low video distortion. By using High Efficiency Video Coding (HEVC) standard we can achieve high compression ratios but unfortunately the distortion caused by packet losses while transmitting HEVC video bit stream over wireless channels cannot be avoided.;This thesis is aimed at designing an Unequal Error Protection (UEP) scheme for efficient transmission of HEVC video bit streams over wireless channels. First, we created a database of video parameters extracted from several test videos and developed a statistical regression model for finding the most important video parameters that play role in causing transmission distortion. Next, we assigned priorities to each individual slice of test video based on regression analysis. Finally, we developed a model to assign a Forward Error Correction (FEC) code rate based on the priority ranking of each video slice. By predicting vital factors in transmission distortion and assigning unequal error protection code rates our scheme provides low transmission distortion and high Peak Signal to Noise Ratio (PSNR) for received videos.