The Research And Implementation Of Scalable Video Transmission System In Heterogeneous Networks

With the rapid development of multimedia technology and network communication technology, video signal, as an important part of multimedia, has been widely applied in many social products and many fields of our life, such as stream-media, video on demand (VOD), video phone, video conference, high-definition TV (HDTV), and video surveillance. At the same time, along with the popularity of intelligent and mobile devices, network access terminals tend to diversify, which all put forward new challenges to video compression and transmission technology.Scalable video coding (SVC) makes high quality video service available to various terminal devices in a wired or wireless way. SVC can provide temporal, spatial and quality scalable services within a wide range of bit rates at a low computation cost. SVC is error-resilient and robust, thus can meet the requirements of video transmission in complex heterogeneous networks. This thesis studied and designed a heterogeneous network-oriented video transmission system based on SVC, aimed to solve the complexity from packet loss in heterogeneous networks and terminals’diversities. This thesis’s main work includes:1. Proposed an algorithm based on multiple decription coding to protect the base layer of scalable video coding in herterogeous networks. Standard scalable video coding includes a base layer and multiple enhancement layers, where the base layer is particularly important, thus, the loss of base layer would seriously affect the quality of video decoding. This dissertation studied heterogeneous network-oriented multiple description coding to solve the packet loss problems, which can be combined with SVC to protect SVC base layer, thus effectively increasing the robustness of SVC in packet-loss environments.2. Proposed a real-time scalable video coding scheme including real-time video transmission and video-on-demand. Although SVC provides open source software model JSVM, its codec is so slow that it cannot meet the needs of real-time video transmission and cannot apply in heterogeneous networks. This thesis presented a real-time SVC coding scheme based on spatial scalability, with proper design of the packetization and unpacktization of video stream, and implenmented real-time video capture transmission and video-on-demand system. Experiments showed that this scheme had achieved better reconstruction performances and real-time transmission.3. Realized heterogenous network-oriented scalable video coding system based on the above schemes. Considering the diversities of terminal devices, this thesis realized SVC encoder and decoder in Windows and Android. Besides, this thesis is valuable for practical engineering application and video transmission over heterogeneous networks.