Patent ID: 8441494

Claim:
In a server having a primary framebuffer for storing display data and a display encoder that uses a secondary framebuffer for transmitting display data to a remote client terminal, a method for preparing display data to be transmitted to the remote client terminal, the method comprising: identifying a bounding box according to drawing commands that cause updates to display data in-the primary framebuffer, the bounding box enclosing a portion of the primary framebuffer to which the drawing commands are directed; marking entries in a data structure, wherein each entry of the data structure corresponds to a different region in the primary framebuffer and the marked entries further correspond the portion of the primary framebuffer; comparing regions of the primary framebuffer corresponding to the marked entries with corresponding regions of the secondary framebuffer, wherein the secondary framebuffer contains display data reflecting a state of the primary framebuffer prior to the updates caused by the drawing commands; and publishing to the display encoder a trimmed data structure containing marked entries only for compared regions having differences, so that the display encoder is able to transmit updated display data of regions of the secondary framebuffer that correspond to marked entries in the trimmed data structure.