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README.md
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## LiDAR
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LiDAR layer was
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- The <b>raw</b> folder contains unprocessed
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- The <b>processed</b> folder contains normalized data
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## Landslides
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Landslides layer
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The <b>raw</b> and
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## Curvature
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- A = (Z1 + Z9) / 2 - Z5
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- B = (Z7 + Z9) / 2 - Z5
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- C = (Z2 + Z8) / 2 - Z5
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- Curvature = A + B + C + D
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- The <b>raw</b> folder contains
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## Hillshade
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The
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- The <b>raw</b> folder contains RGB image with pixel values from 0 to 196.
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- The <b>processed</b> folder
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## NDVI
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## Roughness
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The
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- The <b>raw</b> folder
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- The <b>processed</b> folder contains
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## Slope
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The
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## LiDAR
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The LiDAR layer was derived from a Digital Elevation Model (DEM) with a spatial resolution of 1×1 meter.
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- The <b>raw</b> folder contains the original, unprocessed elevation data.
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- The <b>processed</b> folder contains normalized elevation data. Normalization was performed using a minimum value of 0.0 and a maximum value equal to the highest point in the Biele Karpaty region: 916.335 meters.
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## Landslides
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The Landslides layer represents ground truth data, manually annotated by experts from the State Geological Institute of Dionýz Štúr. A pixel value of <b>1</b> indicates the presence of a landslide.
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The data in both the <b>raw</b> and <b>processed</b> folders are identical, as no additional processing was applied to this layer.
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## Curvature
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The Curvature layer was calculated from the DEM after applying a smoothing filter to reduce noise. A 3×3 kernel was used to smooth the DEM before curvature computation. The curvature was computed using the following formula (see accompanying image for the legend):
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- A = (Z1 + Z9) / 2 - Z5
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- B = (Z7 + Z9) / 2 - Z5
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- C = (Z2 + Z8) / 2 - Z5
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- Curvature = A + B + C + D
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A fixed distance L = 10 meters was used to ensure the output captures broader terrain features and appears smoother.
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- The <b>raw</b> folder contains curvature values directly computed from the formula above.
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- Edge artifacts were cropped.
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- Positive values indicate convex surfaces.
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- Negative values indicate concave surfaces.
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- The <b>processed</b> folder contains a clipped and normalized version:
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- Values were clipped to the range [-2, 2].
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- The clipped values were then normalized to the [0, 1] range using:
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- Minimum = -2 → maps to 0.0
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- Maximum = 2 → maps to 1.0
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- In the normalized data:
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- Values below 0.5 represent concave surfaces
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- Values above 0.5 represent convex surfaces
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## Hillshade
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The Hillshade layer was generated from the DEM using the multidirectional hillshade function in QGIS, with a 45° vertical angle to simulate natural illumination.
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- The <b>raw</b> folder contains an RGB image with pixel values ranging from 0 to 196.
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- The <b>processed</b> folder includes a single selected band extracted from the RGB image. The following enhancements were applied:
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- CLAHE (Contrast Limited Adaptive Histogram Equalization) filter from the OpenCV library:
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- Clip limit: 20
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- Tile grid size: 8×8
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- The output was then normalized to the [0, 1] interval.
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## NDVI
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## Roughness
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The Roughness layer was derived from the DEM using the roughness function in QGIS, which measures the variability of elevation within a local neighborhood.
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- The <b>raw</b> folder a single-band raster with the original roughness values, unprocessed.
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- The <b>processed</b> folder contains a normalized version of the data. The following processing steps were applied:
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- Clipping: Values above 20 were clipped to 20 to reduce the influence of extreme outliers.
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- Logarithmic transformation: The clipped values were transformed using: np.log(roughness + 1.0)
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- Normalization: minimum value set to 0, maximum value set to np.log(21), resulting values were scaled to the range [0, 1]
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## Slope
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The Slope layer was derived from the DEM using the slope function in QGIS, which calculates the steepness of the terrain in degrees.
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- The <b>raw</b> folder contains a single-band raster with the original slope values expressed in degrees of inclination.
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- The <b>processed</b> folder contains a normalized version of the data: minimum value set to 0°, maximum value set to 90°, values were scaled linearly to the range [0, 1].
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