Fig. 1. SIFT registration. (a) Original image; (b) SIFT feature point matching; (c) registration result

Fig. 2. Image preprocessing. (a) Original image; (b) grayscale; (c) binary image

Fig. 3. Upper boundary point of cigarette package

Fig. 4. Upper edge of cigarette package. (a) Edge point; (b) edge line

Fig. 5. Result of rough image registration. (a) Rotation; (b) cutting

Fig. 6. Single⁃angle region

Fig. 7. Edge extraction results of Canny operator

Fig. 8. Results of boundary point screening and separation. (a) Boundary points; (b) points in C4; (c) boundary points

Fig. 9. Result of line fitting and corner position. (a) (b) line l3 and l4; (c) intersection of l3 and l4; (d) position of corner

Fig. 10. Cigarette package image acquisition equipment in operation

Fig. 11. Rough registration rendering

Fig. 12. Corner detection effect

Fig. 13. Original image and registration effect. (a) Template image; (b) real-time image; (c) SRR; (d) SIFT; (e) AKAZE; (f) ORB