The present invention relates to a device, system and a method for extracting physiological information indicative of at least one vital sign of a subject from detected electromagnetic radiation transmitted through or reflected from a subject (14). The device comprises an input interface (30) for receiving a data stream of detection data derived from detected electromagnetic radiation transmitted through or reflected from a skin region of a subject, wherein the detection data comprises wavelength-dependent reflection or transmission information in at least two signal channels representative of respective wavelength portions, a signal mixer (32) for dynamically mixing the at least two signal channels into at least one mixed signal, a process...