| 摘要 |
<p>The invention relates to an image processing permitting the estimation of the distance (D1, D2) between a fixed object (B) and a moving vehicle, on the basis of the rate of enlargement of the image (b) of the object (B) seen from the vehicle. It consists in: - analysing images of the object (B) by means of an image sensor (C) mounted on the vehicle; - centring the images in relation to the velocity vector (V) of the vehicle; - integrating, in a plurality of image memories corresponding respectively to a plurality of predetermined values for the distance, the values of luminance of the pixels of the images analysed successively by the sensor (C), and the values of luminance of the pixels of a succession of images referred to as predicted, the luminance value of each pixel of a predicted image being determined: as a function of the integrated luminance value for the pixel under consideration; as a function of the velocity (V) of the vehicle; as a function of the position of the pixel in the predicted image; and as a function of the distance value corresponding to the memory under consideration; so that the predicted image has an associated enlargement which increases as a function of time; - searching, in the plurality of memories, for that in which the integrated luminance values exhibit the greatest contrast, and inferring therefrom an estimate of distance. Application to a terrain-following device to provide continuous assessment of the distance between an aircraft and the obstructions situated on the ground. <IMAGE></p> |
