Abstract: A video compression system is provided. An encoder may encode video that is decoded by a decoder. The video may be made up of video frames. The decoder may generate approximated display frames for viewing on a display device based on corrected reference frames. The corrected reference frames at the decoder may be created based on approximated reference frames generated based on model state information and based on difference frames provided by the encoder. The encoder may create the difference frames by subtracting approximated reference frames from exact reference frames. The exact reference frames may be created based on a model of a three-dimensional virtual reality environment. The encoder may create the approximated reference frames based on corrected reference frames that are generated based on the difference reference frames.

Abstract: A method by which a client and a server cooperate to render views of a virtual reality world within which a user of the client navigates. The server sends the client a reference view and a model to use to extrapolate the reference view in response to the user's virtual movement. The client sends the server a record of the user's virtual movement. Both the client and the server perform the model-based extrapolation of the reference view. The server also performs an exact update of the reference view. When the extrapolated reference view deviates too much from the updated reference view, the server sends the client the difference between the extrapolated and updated reference views, so that the client can update its reference view.