1. A method for processing high-frequency movements in an optronic system comprising an image sensor functioning with a first signal-acquisition frequency, referred to as the image frequency, each image obtained by the image sensor representing a scene, wherein the method comprises: obtaining signal values representing a movement of said scene from a high-frequency movement sensor, the high-frequency movement sensor generating signal values representing movements in said scene with a second signal-acquisition frequency, referred to as the movement frequency, higher than the image frequency; determining values representing a movement in an image in the course of acquisition by the image sensor from values of the signals representing the movement of said scene, the determination of the values representing the movement of said scene, the determination of the values representing the movement of the image in the course of acquisition by the image sensor comprises a matrix operation between the values of the signals representing the movement of said scene and a conversion matrix; transmitting the values representing the movement of the image in the course of acquisition by the image sensor thus determined to a movement compensation device so that said movement compensation device can implement feedback in the optronic system in order to compensate for the movement of the image in the course of acquisition by the image sensor, the feedback being implemented in the optronic system with a frequency less than or equal to the movement frequency; an inverse matrix of the conversion matrix being determined by a determination method comprising: obtaining a reference image from an original image acquired by the image sensor, simulating first values of the signals representing a movement obtained by the high-frequency movement sensor when the high-frequency movement sensor is subjected to a light beam corresponding to the reference image, applying movements of predetermined movement values to the reference image in order to obtain a set of moved images, for each moved image in the set of moved images, simulating second values of the signals representing a movement obtained by the high-frequency movement sensor when the high-frequency movement sensor is subjected to a light beam corresponding to the moved image, and determining the inverse matrix of the conversion matrix from first and second values of the signals representing a movement obtained by the high-frequency movement sensor and predetermined movement values.