Blind Upmixing for Height and Wide Channels Based on an Image Source Method

In this paper we present a method of synthesizing the height and wide channel signals for stereo upmx to multichannel format beyond 5.1. To provide an improved envelopment, reflections from ceiling and side walls are considered for the height and wide channel synthesis. Early reflections (ERs) corresponding to the spatial sections covered by the height and wide channel speakers are separately synthesized using the image source method, and the parameters for the ER generation are determined from the primary-to-ambient ratio (PAR) estimated from the stereo signal. Later, the synthesized ERs are mixed with decorrelated ambient signals and transmitted to the respective channels. Subjective listening tests verify that listener envelopment can be improved by using the proposed method.