1. A method for analyzing the quality of a glazing, comprising: generating at least one digital image of a test chart produced in reflection by an external surface of the glazing on an outside of the glazing; computing, by at least one processing unit, quantities representative of the quality of the glazing based on the at least one image generated, including dividing the image into a plurality of zones and, for at least one of the zones, computing a local density for each pixel based on a neighborhood of the pixel, the neighborhood including the pixel and plural pixels surrounding the pixel with the pixel as a center of the neighborhood, and after the computing a local density for each pixel, computing a local statistical quantity for each pixel in the zone by determining a local standard deviation or a local rate of change of the local density for each pixel in the zone; comparing values computed for the representative quantities with respect to reference values; in which the test chart exhibits a pattern comprising elements of closed contours arranged periodically, and in which the representative quantities are representative of a deformation of the image of the test chart produced in reflection by the external surface of the glazing on the outside of the glazing.