A realtime large scale terrain visualization algorithm through network

We study the characteristics of massive complex 3D scene data and its remote interactive rendering through networks. Then a new data organization and transfer strategy is proposed. First of all, the server side analysis and partition the 3D scene data source. For each block, an improved SPIHT algorithm is used to code it into compressed data, which is reorganized to form a bit stream for the transmission by networks. The clients adopt a progressive transmission strategy by comprehensive consideration of the needs of the client users, the networks conditions and the data characteristics. Once any length of forehead of a bit-stream is received by the client, it can be added to buffer for 3D scene reconstruction, greatly reducing the time of waiting for display. Then we adopt a LOD scene rendering algorithm based on view-dependent visible region, which reduces the data volume immensely that needs transmission immediately. Simulations results demonstrate that the system is built by our algorithm ensure primely that clients render the scene accurately in real time and users have a good visual experience with low network bandwidth.