Abstract: A computer implemented method, computer system and computer executable program product are disclosed. The method includes running an application with a graphical output by a processor unit of a computer apparatus, analyzing the graphical output to detect and locate pixel changes in consecutive frames of the graphical output; and encoding video data of the graphical output, to a sequence of full frame and partial frame pictures, each of the full frame pictures including image data of an entire frame of the graphical display and each of the partial frame pictures including image data relating only to zones in a frame in which pixel changes where located.

Abstract: A method for digital video distribution in which a program is transmitted as a multicast stream over a network at a base rate. The stream includes a sequence of frames encoding video data, the sequence containing anchor points. A request from a client to begin receiving the program is received at a time subsequent to a given anchor point in the multicast stream. Responsively to the request, a boost stream is transmitted to the client beginning from the given anchor point at an accelerated rate relative to the base rate. The boost stream causes the client to display the video data beginning from the given anchor point and then to join the multicast stream when the boost stream has reached a point of synchronization with the multicast stream.