The invention relates to a device and a method for segmenting objects in an image. The method comprises steps for: the approximate definition of a contour external to the object to be segmented, said contour including a plurality of so-called control points, the determination of a vicinity of candidate points in the vicinity of each control point, the determination of an energy associated with each candidate point in the vicinity of each control point, the convergence of each of the control points (V.sub.i) towards the candidate point, which minimizes said energy, so providing an estimated contour of the object to be segmented. According to the invention, the energy associated with each candidate point includes a colour discrimination term.