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2. Classification land cover. Image classification uses multispectral digital numbers (colour')Most algorithms are per pixel' classifiers. 3. Classification. 4. Manual interpretation e.g. air photos. Human interpretation / classification relies on attributes such as:Shape, pattern, texture, shadows, size, association, tone, colour.
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1. 1 Remote sensing Classification
2. 2 Classification land cover
3. 3 Classification
4. 4 Manual interpretation e.g. air photos
5. 5 Using just one band to classify ?
6. 6
7. 7 The role of multispectral sensing in classificationmultiple bands can be used as input
8. 8 The role of multispectral sensing in classification
9. 9 Band / channel selection controls success
10. 10 sample band correlation coefficients
11. 11 Classification: Band / Channel Selection
12. 12 Two main types of classification Unsupervised: the operator picks the algorithm and number of classes (clusters) useful for a quickie and with little or no ground info
Supervised: the operator picks the algorithm and designs the classes based on ground knowledge takes longer, might be more accurate (!)
13. 13 A> Unsupervised classification
14. 14 Unsupervised result 10 classes (clusters)
15. 15 B> Supervised classification
16. 16 Picking training areas a good sample for each class
17. 17 Training areas (NASA training website)
18. 18 Supervised classification
19. 19 Supervised class assignment
20. 20 Supervised classification methodsa. Minimum distance (below)b. Parallelepiped (right)c. Maximum likelihood (bottom right)
21. 21 Supervised classification: how it works
22. 22 comparison
23. 23 Relative points for the two methods
24. 24 End of classification part 1: Lab 3 on Mondaypart 2: tweaking it out