The present invention relates to a device and method for determining vital sign information of a subject (2). The proposed device comprises an input unit (11) for receiving image data of the subject, said image data including a sequence of images over time, an ROI selection unit (12) for selecting an initial region of interest, ROI, within an image, a feature selection unit (13) for selecting one or more spatial features of a body part within the initial ROI, a motion signal extraction unit (14) for extracting from said image data within the initial ROI the direction and/or amplitude of motion of a subject's body part related to a desired vital sign of the subject, a detection unit (15) for detecting one or more spatial features of said selected spatial features, whose motion is not related to the desired vital sign of the subject, a tracking unit (16) for tracking the initial ROI based on changes of the position of said one or more detected spatial features within the initial ROI, to obtain a final ROI, and a vital signs extraction unit (17) for extracting the desired vital sign from the final ROI.
