Fig. 1. Double-source images
(a): Thermal infrared image; (b): Visible image

Fig. 2. Visible image segmentation
(a): Visible image of sample;(b): Visible image of canopy after segmentation

Fig. 3. Feature points match images

Fig. 4. Initial registration effect of thermal infrared image and reference image
(a): Original thermal infrared image;(b): Initial registration effect

Fig. 5. Image exact matching process
(a): Angle registration; (b): Horizontal registration; (c): Vertical registration; (d): Proportional registration

Fig. 6. Contrast of recognition effect of thermal infrared images
(a): Original thermal infrared image; (b): Energy distribution of original image;(c): Recognition effect of thermal infrared image of canopy; (d): Energy distribution of canopy image after recognition

Fig. 7. Mutual information contrast of recognition effect of thermal infrared images