Wave Field coding in the spacetime frequency domain
Francisco Pinto, Martin Vetterli · IEEE International Conference on Acoustics Speech and Signal Processing · 2008
We present a new method for compressing spatio-temporal audio data for reproduction through wave field synthesis. The data is obtained by sampling the sound field in space at equally-spaced points on a straight line, and transformed into the frequency domain using a spatio-temporal lapped transform. The two-dimensional spectrum is quantized using a psychoacoustic model derived for spatio-temporal frequencies, which estimates the maximum quantization noise power that each frequency can support in order to preserve transparency in the decoded signal. On the decoder side, the inverse lapped transform recovers the spatio-temporal data. In our experimental results, we verified that the bitrate-efficiency can be improved by increasing either the spatial sampling frequency or the spatial resolution of the lapped transform.