Resolve "Creation of images from AIS"

Closes #16 (closed)

skais/ais/ais_trajectory.py

@@ -5,8 +5,9 @@ import numpy as np
 from numba import jit
 from scipy.interpolate import interp1d
 
-from skais.utils.geography import great_circle, position_from_distance
+from skais.utils.geography import great_circle, position_from_distance, get_coord
 from skais.ais.ais_points import AISPoints
+from skais.utils.geometry import bresenham
 
 
 @jit(nopython=True)
@@ -223,3 +224,38 @@ class AISTrajectory(AISPoints):
                 current_label = row[label_column]
                 result.append((row['ts_sec'], current_label))
         return result
+
+    def generate_array_from_positions(self, height=256, width=256, link=True, bounding_box='fit', features=None,
+                                      node_size=0):
+        nb_channels = 1
+        if features is not None:
+            nb_channels = len(features)
+        data = np.zeros((height, width, nb_channels), dtype=np.uint8)
+        if bounding_box != 'fit':
+            raise ValueError("feature not implemented")
+        positions = self.df[['longitude', 'latitude']].to_numpy()
+        min_lon, max_lon = (min(positions[:, 0]), max(positions[:, 0]))
+        min_lat, max_lat = (min(positions[:, 1]), max(positions[:, 1]))
+        for longitude, latitude in positions:
+            x_coord, y_coord = get_coord(latitude, longitude, height, width, min_lat, max_lat, min_lon, max_lon)
+
+            x_lower_bound = max(0, x_coord - node_size)
+            x_upper_bound = min(height - 1, x_coord + node_size)
+
+            y_lower_bound = max(0, y_coord - node_size)
+            y_upper_bound = min(width - 1, y_coord + node_size)
+
+            for x in range(x_lower_bound, x_upper_bound + 1):
+                for y in range(y_lower_bound, y_upper_bound + 1):
+                    data[x, y] = [1]
+
+        if link:
+            lon, lat = positions[0, 0], positions[0, 1]
+            for longitude, latitude in positions[1:]:
+                x_prv, y_prev = get_coord(lat, lon, height, width, min_lat, max_lat, min_lon, max_lon)
+                x_nxt, y_nxt = get_coord(latitude, longitude, height, width, min_lat, max_lat, min_lon, max_lon)
+
+                lon, lat = longitude, latitude
+                for x, y in bresenham(x_prv, y_prev, x_nxt, y_nxt):
+                    data[x, y] = [1]
+        return data