Spatial Parameter Modification for Audio Sweet-Spot Control

The patent extracts only the essential spatial parameters (inter-channel cross-correlation and power ratio) from the multi-channel signal and transmits them as ancillary data, rather than transmitting complete additional channel signals. This extraction approach reduces the additional bit rate from being in the same order of magnitude as the stereo signal to a much smaller amount, while still enabling multi-channel reconstruction at the decoder.

The patent changes the approach from matrix multiplication of channel signals to transmitting explicit spatial parameters (cross-correlation and power ratio) that describe the spatial relationships. This parameter-based approach simplifies the encoding process compared to matrix surround methods, as it requires computing and transmitting only a few numerical parameters rather than performing complex matrix operations on the entire audio signals.

The patent introduces dynamic sweet-spot manipulation by allowing the decoder to adjust the spatial parameters based on the actual listening environment and listener position. The system can dynamically modify the reconstructed multi-channel signal to optimize the listening experience for different positions, making the system adaptable rather than fixed. This is achieved by processing the spatial parameters and adjusting the up-mixing operation based on detected listening conditions.

The patent implements sweet-spot manipulation by modifying the spatial parameters (cross-correlation and power ratio) rather than performing complex signal processing operations on the entire audio signal. This parameter-based manipulation approach reduces computational complexity compared to traditional methods that would require processing the full multi-channel signals. The system changes the spatial relationship parameters to achieve different listening position optimizations.