On parametric representations of the modified group delay

The modified group delay (MODGD) is a group delay based representation suited for processing speech signals. The MODGD is parameterized by three entities, alpha, gamma and lifter_omega. Typically, optimal values of these parameters have to be determined by experimentation. In this paper, we propose a method to automatically determine an optimal value for lifteromega^, which enables the other two parameters to be set to 1.0. This will reduce the optimisation required to obtain meaningful MODGD values directly from the speech signal.