From cefc2221a7220f7d127aaf4c28f07b0c7ce962ea Mon Sep 17 00:00:00 2001
From: inter <inter@qq.com>
Date: Sun, 21 Sep 2025 20:19:06 +0800
Subject: [PATCH] Add File

---
 pcdet/models/dense_heads/point_head_simple.py | 91 +++++++++++++++++++
 1 file changed, 91 insertions(+)
 create mode 100644 pcdet/models/dense_heads/point_head_simple.py

diff --git a/pcdet/models/dense_heads/point_head_simple.py b/pcdet/models/dense_heads/point_head_simple.py
new file mode 100644
index 0000000..1be8415
--- /dev/null
+++ b/pcdet/models/dense_heads/point_head_simple.py
@@ -0,0 +1,91 @@
+import torch
+
+from ...utils import box_utils
+from .point_head_template import PointHeadTemplate
+
+
+class PointHeadSimple(PointHeadTemplate):
+    """
+    A simple point-based segmentation head, which are used for PV-RCNN keypoint segmentaion.
+    Reference Paper: https://arxiv.org/abs/1912.13192
+    PV-RCNN: Point-Voxel Feature Set Abstraction for 3D Object Detection
+    """
+    def __init__(self, num_class, input_channels, model_cfg, **kwargs):
+        super().__init__(model_cfg=model_cfg, num_class=num_class)
+        self.cls_layers = self.make_fc_layers(
+            fc_cfg=self.model_cfg.CLS_FC,
+            input_channels=input_channels,
+            output_channels=num_class
+        )
+
+    def assign_targets(self, input_dict):
+        """
+        Args:
+            input_dict:
+                point_features: (N1 + N2 + N3 + ..., C)
+                batch_size:
+                point_coords: (N1 + N2 + N3 + ..., 4) [bs_idx, x, y, z]
+                gt_boxes (optional): (B, M, 8)
+        Returns:
+            point_cls_labels: (N1 + N2 + N3 + ...), long type, 0:background, -1:ignored
+            point_part_labels: (N1 + N2 + N3 + ..., 3)
+        """
+        point_coords = input_dict['point_coords']
+        gt_boxes = input_dict['gt_boxes']
+        assert gt_boxes.shape.__len__() == 3, 'gt_boxes.shape=%s' % str(gt_boxes.shape)
+        assert point_coords.shape.__len__() in [2], 'points.shape=%s' % str(point_coords.shape)
+
+        batch_size = gt_boxes.shape[0]
+        extend_gt_boxes = box_utils.enlarge_box3d(
+            gt_boxes.view(-1, gt_boxes.shape[-1]), extra_width=self.model_cfg.TARGET_CONFIG.GT_EXTRA_WIDTH
+        ).view(batch_size, -1, gt_boxes.shape[-1])
+        targets_dict = self.assign_stack_targets(
+            points=point_coords, gt_boxes=gt_boxes, extend_gt_boxes=extend_gt_boxes,
+            set_ignore_flag=True, use_ball_constraint=False,
+            ret_part_labels=False
+        )
+
+        return targets_dict
+
+    def get_loss(self, tb_dict=None):
+        tb_dict = {} if tb_dict is None else tb_dict
+        point_loss_cls, tb_dict_1 = self.get_cls_layer_loss()
+
+        point_loss = point_loss_cls
+        tb_dict.update(tb_dict_1)
+        return point_loss, tb_dict
+
+    def forward(self, batch_dict):
+        """
+        Args:
+            batch_dict:
+                batch_size:
+                point_features: (N1 + N2 + N3 + ..., C) or (B, N, C)
+                point_features_before_fusion: (N1 + N2 + N3 + ..., C)
+                point_coords: (N1 + N2 + N3 + ..., 4) [bs_idx, x, y, z]
+                point_labels (optional): (N1 + N2 + N3 + ...)
+                gt_boxes (optional): (B, M, 8)
+        Returns:
+            batch_dict:
+                point_cls_scores: (N1 + N2 + N3 + ..., 1)
+                point_part_offset: (N1 + N2 + N3 + ..., 3)
+        """
+        if self.model_cfg.get('USE_POINT_FEATURES_BEFORE_FUSION', False):
+            point_features = batch_dict['point_features_before_fusion']
+        else:
+            point_features = batch_dict['point_features']
+        point_cls_preds = self.cls_layers(point_features)  # (total_points, num_class)
+
+        ret_dict = {
+            'point_cls_preds': point_cls_preds,
+        }
+
+        point_cls_scores = torch.sigmoid(point_cls_preds)
+        batch_dict['point_cls_scores'], _ = point_cls_scores.max(dim=-1)
+
+        if self.training:
+            targets_dict = self.assign_targets(batch_dict)
+            ret_dict['point_cls_labels'] = targets_dict['point_cls_labels']
+        self.forward_ret_dict = ret_dict
+
+        return batch_dict