Figure 1.
Illustration of tobacco cultivation (FAO, 2018a).
Figure 2.
Tobacco leaf categories based on leaf position.
Figure 3.
Leaf defect categories based on holes or torn positions.
Figure 4.
Mature/ripe leaf subcategories based on the color of tobacco leaf.
Figure 5.
The procedure of leaf area segmentation.
Figure 6.
Area of leaf defects category.
Figure 7.
Small patches applied on the leaf area.
Figure 8.
A set of the threshold to determine the color category.
Figure 9.
A set of the threshold to determine the class in each color category.
Figure 10.
The threshold of hue pixel to segment leaf area.
Figure 11.
The result of a tobacco leaf area segmentation.
Figure 12.
The result of leaf defects detection.
Table 1.
The threshold for local color-based classification.
| Threshold | Hue | Value |
|---|---|---|
| Lower | 15 | 60 |
| Middle | 34 | 127 |
| Upper | 80 | 200 |
Figure 13.
The distribution of hue-value features of a color-based tobacco leaf category.
Figure 14.
The result of color-based tobacco leaf classification.