Abstract: To match a carton check system with the throughput of the high-speed automatic cigarette sorting system,an automatic carton image recognizing method based on morphological processing algorithm was proposed on the basis of unique carton bar code.The binarized images were processed by the square self-adaptive structure element morphological algorithm to minimize the interference of blank zones in a barcode on connected domain and obtain several candidate connected subdomains.By subrange filtering method to position barcode range,by projection method to position the discernible characters,segment figures and complete the recognition of carton information,the simulation experiment was conducted with pictures of cigarette cartons of different brands and randomly placed in Matlab to test the robustness of barcode positioning and segmentation algorithm.The results showed that:1) The method effectively avoided the interferences brought about by character,image information and illuminating noises from carton surface.2) Projection method segmented visible characters from blank zones in barcode quickly,implemented effective figure positioning and performed well in figure segmentation for oblique barcode,low pixel image.3) Low quality or indistinguishable figures were well recognized by weighted matching algorithm combined with fuzzy criterion number recognition algorithm.4) On-site testing showed that the recognition efficiency of the system reached 2 686 times per hour with the accuracy of 95.2%.