Table 2 Selection of best pre-treatment methods (combination of linearization, de-trending and multiplicative correction) from non-Gaussian information indicators and Bhattacharyya distance
From: Hyperspectral imaging: a novel approach for plant root phenotyping
|  | Linearization | De-trending | Multiplicative correction | Non-Gaussian measure rank | Bhattacharyya distance R (rank) | Bhattacharyya distance Ri − Rj (rank) |
|---|---|---|---|---|---|---|
Topsoil | ||||||
1 | Non* | Non | Non | 15 | 0.28 (15) | 9.40 (3) |
2 | Non | Polynomial | Non | 16 | 0.12 (16) | 9.94 (1) |
3 | Non | Derivative | Non | 6 | 4.89 (2) | 8.24 (4) |
4 | Non | ALS | Non | 4 | 4.05 (5) | 9.86 (2) |
5 | Non | Non | SNV | 14 | 4.55 (4) | 5.21 (12) |
6 | Non | Polynomial | SNV | 11 | 9.05 (1) | 5.52 (9) |
7 | Non | Derivative | SNV | 10 | 1.78 (12) | 3.81 (15) |
8 | Non | ALS | SNV | 9 | 2.16 (11) | 4.07 (14) |
9 | Log(1/R) | Non | Non | 8 | 0.30 (14) | 5.30 (11) |
10 | Log(1/R) | Polynomial | Non | 7 | 1.00 (13) | 5.46 (10) |
11 | Log(1/R) | Derivative | Non | 1 | 2.57 (10) | 4.94 (13) |
12 | Log(1/R) | ALS | Non | 2 | 4.63 (3) | 3.67 (16) |
13 | Log(1/R) | Non | SNV | 12 | 3.08 (7) | 6.77 (7) |
14 | Log(1/R) | Polynomial | SNV | 13 | 3.65 (6) | 6.46 (8) |
15 | Log(1/R) | Derivative | SNV | 5 | 3.03 (8) | 7.87 (5) |
16 | Log(1/R) | ALS | SNV | 3 | 2.69 (9) | 7.14 (6) |
Subsoil | ||||||
1 | Non | Non | Non | 13 | 0.26 (15) | 3.18 (16) |
2 | Non | Polynomial | Non | 14 | 0.11 (16) | 3.48 (15) |
3 | Non | Derivative | Non | 15 | 2.76 (12) | 7.04 (11) |
4 | Non | ALS | Non | 10 | 2.56 (13) | 6.20 (12) |
5 | Non | Non | SNV | 9 | 3.68 (9) | 9.36 (6) |
6 | Non | Polynomial | SNV | 7 | 3.87 (8) | 9.88 (5) |
7 | Non | Derivative | SNV | 16 | 3.89 (7) | 4.52 (14) |
8 | Non | ALS | SNV | 12 | 5.84 (6) | 7.39 (10) |
9 | Log(1/R) | Non | Non | 8 | 7.44 (2) | 11.95 (3) |
10 | Log(1/R) | Polynomial | Non | 11 | 1.10 (14) | 10.61 (4) |
11 | Log(1/R) | Derivative | Non | 5 | 3.61 (10) | 8.87 (7) |
12 | Log(1/R) | ALS | Non | 2 | 5.91 (5) | 13.62 (1) |
13 | Log(1/R) | Non | SNV | 3 | 6.60 (3) | 8.19 (8) |
14 | Log(1/R) | Polynomial | SNV | 4 | 6.37 (4) | 7.56 (9) |
15 | Log(1/R) | Derivative | SNV | 6 | 3.36 (11) | 5.07 (13) |
16 | Log(1/R) | ALS | SNV | 1 | 10.52 (1) | 11.51 (2) |