feat: initial commit - massive-cloud point cloud processing system

alg/point_porj/preprocessing/noise.py

@@ -0,0 +1,29 @@
+from __future__ import annotations
+
+import copy
+
+import numpy as np
+import open3d as o3d
+
+
+class GaussianNoiseAdder:
+    """Add Gaussian noise to an Open3D point cloud."""
+
+    def __init__(self, noise_std: float = 4.0, seed: int | None = None) -> None:
+        self.noise_std = noise_std
+        self.seed = seed
+
+    def apply(self, pointcloud: o3d.geometry.PointCloud) -> o3d.geometry.PointCloud:
+        noisy = copy.deepcopy(pointcloud)
+        points = np.asarray(noisy.points)
+        rng = np.random.default_rng(self.seed)
+        noise = rng.normal(0, self.noise_std, points.shape)
+        noisy.points = o3d.utility.Vector3dVector(points + noise)
+        return noisy
+
+    def noise_level(self, clean: o3d.geometry.PointCloud, noisy: o3d.geometry.PointCloud) -> float:
+        clean_points = np.asarray(clean.points)
+        noisy_points = np.asarray(noisy.points)
+        if clean_points.shape != noisy_points.shape:
+            raise ValueError("Clean and noisy point clouds must have the same point count.")
+        return float(np.mean(np.linalg.norm(noisy_points - clean_points, axis=1)))