From 5ecd5bb51757ba1d2e5127db87eed50179546665 Mon Sep 17 00:00:00 2001
From: inter <inter@qq.com>
Date: Sun, 21 Sep 2025 20:19:00 +0800
Subject: [PATCH] Add File

---
 .../backbones_3d/vfe/dynamic_mean_vfe.py      | 76 +++++++++++++++++++
 1 file changed, 76 insertions(+)
 create mode 100644 pcdet/models/backbones_3d/vfe/dynamic_mean_vfe.py

diff --git a/pcdet/models/backbones_3d/vfe/dynamic_mean_vfe.py b/pcdet/models/backbones_3d/vfe/dynamic_mean_vfe.py
new file mode 100644
index 0000000..b4c5b06
--- /dev/null
+++ b/pcdet/models/backbones_3d/vfe/dynamic_mean_vfe.py
@@ -0,0 +1,76 @@
+import torch
+
+from .vfe_template import VFETemplate
+
+try:
+    import torch_scatter
+except Exception as e:
+    # Incase someone doesn't want to use dynamic pillar vfe and hasn't installed torch_scatter
+    pass
+
+from .vfe_template import VFETemplate
+
+
+class DynamicMeanVFE(VFETemplate):
+    def __init__(self, model_cfg, num_point_features, voxel_size, grid_size, point_cloud_range, **kwargs):
+        super().__init__(model_cfg=model_cfg)
+        self.num_point_features = num_point_features
+
+        self.grid_size = torch.tensor(grid_size).cuda()
+        self.voxel_size = torch.tensor(voxel_size).cuda()
+        self.point_cloud_range = torch.tensor(point_cloud_range).cuda()
+
+        self.voxel_x = voxel_size[0]
+        self.voxel_y = voxel_size[1]
+        self.voxel_z = voxel_size[2]
+        self.x_offset = self.voxel_x / 2 + point_cloud_range[0]
+        self.y_offset = self.voxel_y / 2 + point_cloud_range[1]
+        self.z_offset = self.voxel_z / 2 + point_cloud_range[2]
+
+        self.scale_xyz = grid_size[0] * grid_size[1] * grid_size[2]
+        self.scale_yz = grid_size[1] * grid_size[2]
+        self.scale_z = grid_size[2]
+
+    def get_output_feature_dim(self):
+        return self.num_point_features
+
+    @torch.no_grad()
+    def forward(self, batch_dict, **kwargs):
+        """
+        Args:
+            batch_dict:
+                voxels: (num_voxels, max_points_per_voxel, C)
+                voxel_num_points: optional (num_voxels)
+            **kwargs:
+
+        Returns:
+            vfe_features: (num_voxels, C)
+        """
+        batch_size = batch_dict['batch_size']
+        points = batch_dict['points'] # (batch_idx, x, y, z, i, e)
+
+        # # debug
+        point_coords = torch.floor((points[:, 1:4] - self.point_cloud_range[0:3]) / self.voxel_size).int()
+        mask = ((point_coords >= 0) & (point_coords < self.grid_size)).all(dim=1)
+        points = points[mask]
+        point_coords = point_coords[mask]
+        merge_coords = points[:, 0].int() * self.scale_xyz + \
+                        point_coords[:, 0] * self.scale_yz + \
+                        point_coords[:, 1] * self.scale_z + \
+                        point_coords[:, 2]
+        points_data = points[:, 1:].contiguous()
+        
+        unq_coords, unq_inv, unq_cnt = torch.unique(merge_coords, return_inverse=True, return_counts=True)
+
+        points_mean = torch_scatter.scatter_mean(points_data, unq_inv, dim=0)
+        
+        unq_coords = unq_coords.int()
+        voxel_coords = torch.stack((unq_coords // self.scale_xyz,
+                                    (unq_coords % self.scale_xyz) // self.scale_yz,
+                                    (unq_coords % self.scale_yz) // self.scale_z,
+                                    unq_coords % self.scale_z), dim=1)
+        voxel_coords = voxel_coords[:, [0, 3, 2, 1]]
+        
+        batch_dict['voxel_features'] = points_mean.contiguous()
+        batch_dict['voxel_coords'] = voxel_coords.contiguous()
+        return batch_dict