1. Method for estimating the image depth map of a scene, which comprises the steps of: providing (E 1 ) an image in which the focus depends on the depth and wavelength of the considered object points of the scene, using a longitudinal chromatic optical system, determining (E 2 ) a set of spectral images from the image provided by the longitudinal chromatic optical system, deconvoluting (E 3 ) the spectral images in order to provide estimated spectral images with extended depth of field, and analyzing (E 4 ) a cost criterion that is dependent on the estimated spectral images with extended depth of field, in order to provide an estimated depth map ({circumflex over (Z)}(x,y)).