Evaluation of conventional digital camera scenes for Thematic Information Extraction

Figure 4: The classified image obtained using Maximum Likelihood classifier for
Merbok River estuary (Green = Forest, Blue = Water, Orange = Land, and Light Blue =
Turbid Water)
(B) Area B
The Kappa coefficient and overall accuracy value for the three-classification technique
are shown in Table 4. The others accuracy assessment results are presented in Tables 5
and 6, where the Kappa coefficient, the confusion matrix and the accuracy of each class
using Maximum Likelihood, minimum distance-to-mean and parallelepiped classification
are given, respectively. From the present analysis, one can see that the Maximum
Likelihood classifier produced the best image classification accuracy with the highest
overall accuracy and Kappa coefficient. The overall classification accuracies achieved by
the proposed Maximum Likelihood classifier on the digital image is 95.00 %. This
followed by the Minimum Distance-to-Mean with the overall classification accuracy of
73.00%, and Parallelepiped resulted in the overall classification accuracy of 1.00%. A
classified image using Maximum Likelihood classifier is shown in Figure 5.
Table 4: The overall classification accuracy and Kappa coefficient
| Classification method |
Overall classification accuracy (%) |
Kappa coefficient |
| Maximum Likelihood |
95.000 |
0.866 |
| Minimum Distance-to-Mean |
73.000 |
0.457 |
| Parallelepiped |
1.000 |
0.008 |
Table 5: The confusion matrix results
| Classified Data |
Reference Data |
| Grass |
Water |
Land |
Urban |
Total |
| Grass |
21 |
1 |
0 |
0 |
22 |
| Water |
0 |
154 |
1 |
0 |
155 |
| Land |
2 |
2 |
12 |
4 |
20 |
| Urban |
0 |
0 |
0 |
3 |
3 |
| Total |
23 |
157 |
13 |
7 |
200
|
Table 6: The accuracy of each class using Maximum Likelihood classification.
| Class |
Maximum Likelihood |
| Producer Accuracy (%)
|
User Accuracy (%) |
| Grass
| 91.304
| 95.455 |
| Water
| 98.089
| 99.355 |
| Land |
92.308 |
60.000 |
| Urban |
42.857 |
100.000
|