# Dual-Window Superpixel Data Augmentation for Hyperspectral Image Classification
## 3 Results
### Datasets  
This section describes the characteristics, including the compositions of the disjoint training and testing sets, of the six scenes used to evaluate the performance of the proposed data augmentation techniques. Three widely available hyperspectral scenes [27] from the literature (standard dataset, from now onwards) and four large multispectral images from river basins belonging to the the Galicia dataset [28] were considered. All the images of the Galicia dataset were captured at an altitude of 120 m by a UAV mounting a MicaSense RedEdge multispectral camera [29]. Its spatial resolution is 0.082 m/pixel and it covers a spectral range from 475 to 840 nm. Figures 7 and 8 display the false color composite and reference data for the scenes of the standard and Galicia datasets, respectively. More specifically, the Salinas Valley, Pavia University and Pavia Centre scenes from the standard dataset along with the River Oitaven, Creek Ermidas, Eiras Dam and River Mestas scenes from the Galicia dataset were selected for the experiments. The detailed descriptions of the scenes are as follows:  
1. Salinas valley (Salinas): Mixed vegetation scene in California. It was obtained by the NASA AVIRIS sensor with a spatial resolution of 3.7 m/pixel, covering a spectral range from 400 to 2500 nm. The image is \(512\times 217\) pixels and has 220 spectral bands. The reference information contains sixteen classes. The scene is located at \(36^{\circ}39^{\prime}33.8^{\prime\prime}\) N 121\({}^{\circ}\)39\({}^{\prime}\)58.7\({}^{\prime\prime}\) W. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \# & **Type** & **Output Shape** & **Activation** & **Filter Size** & **Stride** & **Padding** \\ \hline
1 & 2D-Convolutional & \(25\times 25\times 128\) & ELU & \(1\times 1\) & \(1\times 1\) & None \\
2 & 2D-MaxPooling & \(12\times 12\times 128\) & - & \(2\times 2\) & \(2\times 2\) & None \\
3 & 2D-Convolutional & \(10\times 10\times 256\) & ELU & \(3\times 3\) & \(1\times 1\) & None \\
4 & 2D-MaxPooling & \(5\times 5\times 256\) & - & \(2\times 2\) & \(2\times 2\) & None \\
5 & Dropout & \(5\times 5\times 256\) & - & - & - & - \\
6 & Flatten & \(1\times 6400\) & - & - & - & - \\
7 & Dense & \(1\times 256\) & ELU & - & - & - \\
8 & Dropout & \(1\times 256\) & - & - & - & - \\
9 & Dense & \(1\times C\) & Softmax & - & - & - \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Neural network architecture. 2. Pavia University (PaviaU): Urban scene acquired by the ROSIS-03 sensor over the city of Pavia, Italy. Its spatial resolution is 2.6 m/pixel and covers a spectral range from 430 to 860 nm. The image is \(610\times 340\) pixels and has 103 spectral bands. The ground truth contains nine classes. The scene is located at 45\({}^{\circ}\)12\({}^{\prime}\)09.2\({}^{\prime\prime}\) N 9\({}^{\circ}\)08\({}^{\prime}\)08.6\({}^{\prime\prime}\) E.
3. Pavia Centre (PaviaC): Urban scene acquired by the ROSIS-03 sensor over the city of Pavia, Italy. Its spatial resolution is 2.6 m/pixel and covers a spectral range from 430 to 860 nm. The image is 1096 \(\times\) 715 pixels and has 103 spectral bands. The ground truth contains nine classes. The scene is located at 45\({}^{\circ}\)11'12.7\({}^{\prime\prime}\) N 9\({}^{\circ}\)08\({}^{\prime}\)48.7\({}^{\prime\prime}\) E.
4. River Oitaven (Oitaven): Multispectral vegetation scene of the Oitaven river from Pontevedra, Spain. The image is \(6689\times 6722\) pixels and has 5 bands. The scene is located at 42\({}^{\circ}\)22\({}^{\prime}\)15.3\({}^{\prime\prime}\) N 8\({}^{\circ}\)25'47.4\({}^{\prime\prime}\) W.
5. Creek Ermidas (Ermidas): Multispectral vegetation scene showing the point where Creek Ermidas and River Oitaven meet, from Pontevedra, Spain. The image is 11,924 \(\times\) 18,972 pixels and has 5 bands. The scene is located at 42\({}^{\circ}\)22'51.9\({}^{\prime\prime}\) N 8\({}^{\circ}\)24'53.5\({}^{\prime\prime}\) W.
6. Eiras Dam (Eiras): Multispectral vegetation scene showing the reservoir that supplies running water to the town of Vigo from Pontevedra, Spain.