From 05830e05a6de84185014ad09f974ded64965e578 Mon Sep 17 00:00:00 2001
From: inter <inter@qq.com>
Date: Sun, 21 Sep 2025 20:18:53 +0800
Subject: [PATCH] Add File

---
 .../SemanticSeg/pyramid_ffn.py                | 77 +++++++++++++++++++
 1 file changed, 77 insertions(+)
 create mode 100644 pcdet/models/backbones_3d/focal_sparse_conv/SemanticSeg/pyramid_ffn.py

diff --git a/pcdet/models/backbones_3d/focal_sparse_conv/SemanticSeg/pyramid_ffn.py b/pcdet/models/backbones_3d/focal_sparse_conv/SemanticSeg/pyramid_ffn.py
new file mode 100644
index 0000000..29773a0
--- /dev/null
+++ b/pcdet/models/backbones_3d/focal_sparse_conv/SemanticSeg/pyramid_ffn.py
@@ -0,0 +1,77 @@
+import torch
+import torch.nn as nn
+from .basic_blocks import BasicBlock2D
+from .sem_deeplabv3 import SemDeepLabV3
+
+class PyramidFeat2D(nn.Module):
+
+    def __init__(self, optimize, model_cfg):
+        """
+        Initialize 2D feature network via pretrained model
+        Args:
+            model_cfg: EasyDict, Dense classification network config
+        """
+        super().__init__()
+        self.model_cfg = model_cfg
+        self.is_optimize = optimize
+
+        # Create modules
+        self.ifn = SemDeepLabV3(
+            num_classes=model_cfg.num_class,
+            backbone_name=model_cfg.backbone,
+            **model_cfg.args
+        )
+        self.reduce_blocks = torch.nn.ModuleList()
+        self.out_channels = {}
+        for _idx, _channel in enumerate(model_cfg.channel_reduce["in_channels"]):
+            _channel_out = model_cfg.channel_reduce["out_channels"][_idx]
+            self.out_channels[model_cfg.args['feat_extract_layer'][_idx]] = _channel_out
+            block_cfg = {"in_channels": _channel,
+                         "out_channels": _channel_out,
+                         "kernel_size": model_cfg.channel_reduce["kernel_size"][_idx],
+                         "stride": model_cfg.channel_reduce["stride"][_idx],
+                         "bias": model_cfg.channel_reduce["bias"][_idx]}
+            self.reduce_blocks.append(BasicBlock2D(**block_cfg))
+
+    def get_output_feature_dim(self):
+        return self.out_channels
+
+    def forward(self, images):
+        """
+        Predicts depths and creates image depth feature volume using depth distributions
+        Args:
+            images: (N, 3, H_in, W_in), Input images
+        Returns:
+            batch_dict:
+                frustum_features: (N, C, D, H_out, W_out), Image depth features
+        """
+        # Pixel-wise depth classification
+        batch_dict = {}
+        ifn_result = self.ifn(images)
+
+        for _idx, _layer in enumerate(self.model_cfg.args['feat_extract_layer']):
+            image_features = ifn_result[_layer]
+            # Channel reduce
+            if self.reduce_blocks[_idx] is not None:
+                image_features = self.reduce_blocks[_idx](image_features)
+
+            batch_dict[_layer+"_feat2d"] = image_features
+        
+        if self.training:
+            # detach feature from graph if not optimize
+            if "logits" in ifn_result:
+                ifn_result["logits"].detach_()
+            if not self.is_optimize:
+                image_features.detach_()
+
+        return batch_dict
+
+    def get_loss(self):
+        """
+        Gets loss
+        Args:
+        Returns:
+            loss: (1), Network loss
+            tb_dict: dict[float], All losses to log in tensorboard
+        """
+        return None, None