Fig. 1. Corn image segmentation (close shot)
(a): Original image; (b): Image after segmentation

Fig. 2. Corn image segmentation (distant shot)
(a): Original image; (b): Image after segmentation

Fig. 3. Image segmentation of cornfield
(a): Original image; (b): Image after segmentation

Fig. 4. Black pixel statistics (up and down 200 rows)
(a): The pixel statistics in first 200 rows;(b): The pixel statistics in last 200 rows

Fig. 5. Blackpixel statistics (left and right 200 columns)
(a): The pixel statistics in first 200 columns;(b): The pixel statistics in last 200 columns

Fig. 6. Black pixel statistics (346 columns in the middle)

Fig. 7. Processing region

Fig. 8. The proportion of black pixels in total pixels