Abstract
The Image Method (IM) has become increasingly popular for small-room acoustics simulations. While it gives an exact solution of the wave equation in shoebox-rooms with rigid walls, the assumption of rigidity is not valid in real rooms. Based on spherical wave reflection from an infinite wall, several authors have independently developed what is known as the Complex Image Method (CIM). However, its adoption in room acoustics has been rare, although it has been shown to give performance equivalent to the boundary element method in shoebox rooms with soft-walls. In this paper, we review the theory behind CIM and provide a Python implementation to study directional scattering patterns as a function of wall impedance. For a highly symmetrical room, room impulse responses simulated with CIM are shown to have less so-called "sweeping echoes" than those simulated by IM.