Signal processing apparatus and non-transitory computer readable medium

A signal processing apparatus comprising:

• a signal processing unit configured to train a neural network into which M input vectors corresponding to M detector devices having N-fold symmetry are input (M is an integer equal to or greater than 2, and N is an integer equal to or greater than 2) and which outputs K output vectors corresponding to K signal sources having N-fold symmetry (K is an integer equal to or greater than 2);
• a determination unit configured to determine a combination of commutative weights, among a plurality of weights included in a weight matrix of the neural network, in terms of a symmetrical operation based on an order of rotational symmetry N based on a number of microphone devices M, a number of speakers K, and the order of rotational symmetry N;
• and
• a training unit configured to assign a same parameter to multiple weights belonging to a same weight combination and train the neural network, and generate a trained neural network.