Abstract: The method of detecting single postal items and multiple overlapping postal items in a postal sorting installation consists in analyzing images (5) representing postal items (6) viewed from in front, and in applying to each image an outline-extracting process (10) in order to recognize items (6) having an outline (10) of substantially constant height as being single items. In this method, the reliability with which single items is detected is improved, and the digital image used for analysis purposes can be the digital image which is also used for optical character recognition processing in the postal sorting installation.

Abstract: The method of detecting single postal items and multiple overlapping postal items in a postal sorting installation consists in analyzing images (5) representing postal items (6) viewed from in front, and in applying to each image an outline-extracting process (10) in order to recognize items (6) having an outline (10) of substantially constant height as being single items. In this method, the reliability with which single items is detected is improved, and the digital image used for analysis purposes can be the digital image which is also used for optical character recognition processing in the postal sorting installation.

Abstract: The method of detecting overlapping postal items in a postal sorting installation (1) consists in detecting variation in the length of each item by causing each item to go past a plurality of proximity detectors (4, 5, 6, 7). The proximity detectors are situated at different points of the sorting installation (1) and they are configured to evaluate the length of each item. As they pass through the sorting installation, overlapping items shift progressively relative to one another due, in particular, to friction. Thus, the total length of a set of overlapping items tends to vary, such that evaluating variation in the length of each potential item serves to provide information that is reliable for detecting overlaps. Since it is relatively easy to evaluate the length of an item, the performance of the installation is improved at low cost.