Inspecting machine for leather and inspection method applicable to said machine

A method (200) for inspecting a leather (50) in an inspecting machine (100) comprising the following steps:

• capturing (201) an image (60) of said leather (50) using each one of said contact image sensors (8, 9);
• in each one of said images, identifying (202) a corresponding plurality of said geometrical features (53) of said leather (50);
• defining (203) a numerical representation (61) for each geometrical feature (53), said numerical representation (61) comprising at least one pair of coordinates (x, y) of said geometrical feature (53), relative to a reference system of a corresponding contact image sensor (8, 9);
• for each pair of contact image sensors (8, 9) whose fields of view (10, 11) have mutually overlapping first portions (10a, 11a), identifying (204) each pair of numerical representations (61) corresponding to a same geometrical feature (53) captured in said first portions (10a, 11a) by the contact image sensors (8, 9) of said pair;
• for each one of said pairs of contact image sensors (8, 9), defining (205) an affine transformation (Tij) that transforms the coordinates (x, y) of the numerical representations (61) relating to a first sensor (8, 9) of said pair of sensors and that belongs to one of said pairs of numerical representations (61) in the coordinates (x, y) of the corresponding numerical representations (61) relating to a second sensor (8, 9) of said pair of sensors, or that minimizes a difference therebetween;
• and
• for each one of the coordinates (x, y) of one or more of said numerical representations (61), calculating (206) corresponding transformed coordinates (x*, y*) relative to a common reference system by applying said affine transformations (Tij), in order to obtain a digital map (62) of said leather (50).