A method for estimating the distance between a position of an observer and a target, using at least one image generated by a digital image generator from the position of the observer, the method comprising a sequence of steps comprising: - a detection and identification step consisting in detecting and identifying at least one target in the image, from at least one list of known targets, the detection and identification step comprising: • a detection sub-step (E1A) consisting in detecting at least one target in the image; and • a recognition and identification sub-step (E1B) consisting in assigning a class to the detected target; - an orientation estimation step consisting in determining the orientation of the target identified in the image by comparing its observation in the image with orientation estimation models of this target previously elaborated and present in the database (14, 20); and - a distance estimation step, the distance estimation step comprising: • a measurement sub-step (E3A) consisting of measuring, on the image, the length dp of at least one characteristic segment (S1, S2, S3) of the target; • the determination of an apparent length dm of the characteristic segment (S1, S2, S3), corresponding to the actual length of the characteristic segment (S1, S2, S3) taking into account the geometry and the orientation of the target with respect to the image generator, determined in the orientation estimation step;and • a calculation sub-step (E3B) consisting in calculating the distance between the position of the observer and the target using the following expression: D = dm / dp. θ in which θ represents the spatial resolution of the image generator, to which angle of view in the reality corresponds the length of a pixel in the image. - a detection and identification step consisting in detecting and identifying at least one target in the image, from at least one list of known targets, the detection and identification step comprising: • a detection sub-step (E1A) consisting in detecting at least one target in the image; and • a recognition and identification sub-step (E1B) consisting in assigning a class to the detected target; • a detection sub-step (E1A) consisting in detecting at least one target in the image; and • a recognition and identification sub-step (E1B) consisting in assigning a class to the detected target; - an orientation estimation step consisting in determining the orientation of the target identified in the image by comparing its observation in the image with orientation estimation models of this target previously elaborated and present in the database (14, 20); and - a distance estimation step, the distance estimation step comprising: • a measurement sub-step (E3A) consisting of measuring, on the image, the length dp of at least one characteristic segment (S1, S2, S3) of the target; • the determination of an apparent length dm of the characteristic segment (S1, S2, S3), corresponding to the actual length of the characteristic segment (S1, S2, S3) taking into account the geometry and the orientation of the target with respect to the image generator, determined in the orientation estimation step;and • a calculation sub-step (E3B) consisting in calculating the distance between the position of the observer and the target using the following expression: D = dm / dp. θ in which θ represents the spatial resolution of the image generator, to which angle of view in the reality corresponds the length of a pixel in the image. • a measurement sub-step (E3A) consisting of measuring, on the image, the length dp of at least one characteristic segment (S1, S2, S3) of the target; • the determination of an apparent length dm of the characteristic segment (S1, S2, S3), corresponding to the actual length of the characteristic segment (S1, S2, S3) taking into account the geometry and the orientation of the target with respect to the image generator, determined in the orientation estimation step;and • a calculation sub-step (E3B) consisting in calculating the distance between the position of the observer and the target using the following expression: D = dm / dp. θ in which θ represents the spatial resolution of the image generator, to which angle of view in the reality corresponds the length of a pixel in the image.