Processing acoustic signals to detect sound sources in a sound scene. The method includes: obtaining a plurality of signals representative of the sound scene, captured by a plurality of microphones of predefined positions; based on the signals captured by the microphones and on the positions of the microphones, applying a quantization of directional measurements of sound intensity and establishing a corresponding acoustic activity map in a sound source localization space, the space being of dimension N; constructing at least one vector basis of dimension less than N; projecting the acoustic activity map onto at least one axis of the vector basis; and searching for at least one local peak of acoustic activity in the map projection, an identified local peak corresponding to the presence of a sound source in the scene.