Video Transmission Over Wireless Networks Using NS 3

Video is one of the most important and also one of the most challenging types of traffic on communication networks.One of the challenges arises because communication networks especially wireless communication networks can insert errors into video,and since compressed video is fragile in the presence of errors meaning a single error can propagate over a large portion of the video thereby distorting the video and presenting a degraded video which may or may not be viewable.This thesis protect and conserve the quality of the video and multimedia data that is being sent over a wireless channel by employing error concealing methodologies at the receiver.At the same time,we investigate quality of video during the transimission by employing some quality of service(QoS)metrics like peak signal to noise ratio(PSNR)and structural similarity parameter(SSIM).Further,when we using current simulation tools to measure the performance of video transimission,teh researchers usually acquire network-level performance metrics,such as throughput,delay and jitter without acquiring data that can allow them to evaluate video delivering quality by comparing the original and distorted video.However,network-level performance metrics cannot evaluate the delivered video quality accuracy,thus some novel simulation tool-sets like Evalvid and MSU video quality measurement tool have been proposed.This is demonstrated in a simulation environment using NS 3 installed on an Ubuntu 16.0.04 LTS platform and Evalvid installed in the NS 3 environment.MSU video quality measurement tool(VQMT)is used to measure the video quality after transmission and also the visual quality a user may view after transmission over the wireless network.An H.264/AVC tool called JM reference software which allows the encoding and decoding of multimedia files from the macroblock level therefore allowing space for easy manipulations of the individual frames and fields of the video is used before the video is placed in the simulation environment.It is from H.264/AVC reference program that we are able to manipulate some key features to get the best out of the H.264/AVC video codec which no research work has explored and found yet.In this thesis,Evalvid default sample LTE+EPC network were used.It instantiates eNodeB,attaches one user equipment(UE)per eNodeB starts a flow for each UE to and from a remote host.It also starts yet another flow between each UE pair.It also has a maximum transfer unit(mtu)of 1500 byte.This is a default network found in the Evalvid framework and it flexible to use as programming code can be changed to suit the need of the researcher.In order to meet the standard set by the main error robust technique Flexible Macroblock Ordering(FMO),some key parameter settings must be controlled because not all the parameter setting that can be used to encode a video whiles encoding from the macroblock level has a direct impact on correcting or concealing macroblocks of a video.Therefore this thesis concentrated on finding relevant parameter settings that will have a direct impact on the video's quality by evaluating the Peak Signal Noise Ratio of the reconstructed video after transmission by comparing both the original raw video with the reconstructed video file after transmission.These parameters include num_slice_group_minus1,Profile_IDC,quantization parameter,RDOptimization and number of B frames.When simulation was performed,it was realized that the changing of these parameters protect the video frames in a way that using an error concealment methodology like Flexible Macroblock Ordering will protect the macroblocks in a video and therefore produces good quality video as is seen in the simulation results presented in this thesis.The results are comparatively close which means this new technique is good and can be used.The technique was compared with results of FMO to show its significance.Also this technique is easy to implement and can be used easily compared with other systems developed by other researchers that have proprietary measures and sometimes does not include appropriate documentation that can allow researchers to do further research or other relevant purposes.One disadvantage to this technique was the more video frames that a video has,the more degradation occurs,which means this technique does not apply to wireless network like the wireless LTE network used in this thesis.This was the only disadvantage to this technique and it therefore creates room for further research work to find out why degradation increases the larger the video file becomes.