A SPARSITY BASED APPROACH FOR ACOUSTIC ROOM IMPULSE RESPONSE SHORTENING

Acoustic room impulse response shortening is a method for reducing the effect of unwanted reverberations in a surround sound system such as reflections from the walls, floor and corners and cross-talk from the loudspeakers. Impulse response shortening is a softer requirement than inversion, that reduces the effect of room impulse responses rather than removing them completely as in inversion. Thus, shortening allows for some reverberation to be present in the shortened responses. Such an approach results in shorter filters and less cross-talk. This paper proposes a sparse formulation approach for impulse response shortening. We assume that the resulting room impulse responses can be estimated by microphones located at or near the listening positions. Through simulations, it is demonstrated that cross-talk as low as -40dB can be achieved, with fast convergence.