A system and methods are shown for generating a transport stream. An application reads a transport stream file stored in memory. The application provides access to the transport stream file to a graphics card using a multimedia peripheral port (MPP). The MPP is used to provide data from the transport stream file to a transport stream demultiplexer. The application determines a desired transmission rate from the data present between program clock references in the transport stream file. The application suspends transmissions to the transport stream demultiplexer to allow a transmission bit-rate to match the desired bit-rate. The application also suspends transmission when the receiving transport demultiplexer determines its buffers are nearly full.