A method of processing a signal including at least a component representative of a periodic phenomenon in a living being includes obtaining at least one first signal having at least a component representative of a periodic phenomenon in a living being. Separate data representative of at least a periodic component of motion of the living being are obtained by obtaining a sequence of images showing the living being, synchronized with the at least one first signal, and carrying out video-based motion analysis of the sequence of images. The data are used at least to suppress a component of the first signal corresponding to the periodic component of motion of the living being.