A composite multimedia presentation may be represented by a sequence of virtual media data packets. An algorithm is presented for ordering these virtual media data packets so as to minimize the initial delay required to transfer the composite stream from a media server to a client. This algorithm has been implemented as part of the IBM Toolkit for MPEG-4.

Three methods for evaluating the surface coordinates, first derivatives, and normal vectors of a NURB surface are compared. These methods include forward differencing, knot insertion, and a tow-stage Cox-de Boor technique. The computational complexity of each of these techniques is analyzed and summarized. The use of Hermite functions is shown to yield a poor approximation for the shading functions of a NURB surface. An improved method for computing derivatives by knot insertion is presented. An efficient algorithm for computing the foward difference matrix and a method for using foward differencing to compute the first derivatives of a NURB surface are also presented.