PMDNet — Progressive Mirror Detection
Pretrained weights for PMDNet, the model introduced in the CVPR 2020 paper Progressive Mirror Detection.
Model Description
PMDNet progressively detects mirror surfaces by leveraging multi-scale contrast cues and relational context.
Architecture overview:
- Backbone — ResNeXt-101 (32×4d), producing feature maps at four scales.
- Contrast Module (
Contrast_Module_Deep) — at each scale, dilated convolutions capture local–context differences, then four stackedContrast_Block_Deepunits compute pairwise local–context subtractions at two dilation rates. Outputs are aggregated with CBAM (channel + spatial attention). - Relation Attention (
Relation_Attention/RAttention) — criss-cross attention over rows, columns, and both diagonals, enabling long-range relational reasoning without a full self-attention map. - Decoder — four transposed-convolution upsampling stages with CBAM refinement produce intermediate saliency predictions (
f4 → f1), each gated by the previous scale's prediction for progressive focus. - Edge Branch — extracts edge features from
layer1fused with high-levelcbam_4context, producing an explicit edge map. - Refinement — a single 1×1 conv fuses the original image, all four scale predictions, and the edge map into the final mirror mask.
Input: RGB image, resized to 416×416.
Output (eval): (f4, f3, f2, f1, edge, final) — sigmoid-activated predictions at input resolution.
Optional CRF post-processing is applied to the final prediction.
Weights
| File | Size | Description |
|---|---|---|
pmd.pth |
~414 MB | Full model weights (ResNeXt-101 backbone + decoder) |
Usage
import torch
from torchvision import transforms
from PIL import Image
from model.pmd import PMD # from the official code release
model = PMD()
model.load_state_dict(torch.load("pmd.pth", map_location="cpu"))
model.eval()
transform = transforms.Compose([
transforms.Resize((416, 416)),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225]),
])
img = Image.open("your_image.jpg").convert("RGB")
x = transform(img).unsqueeze(0)
with torch.no_grad():
f4, f3, f2, f1, edge, final = model(x)
# `final` is the mirror mask prediction (values in [0, 1])
Full inference script with CRF post-processing: see code_minimal/infer.py.
Dataset
Trained on the PMD dataset (5,095 training images with mirror masks and edge maps).
Performance
| Method | F_β | MAE |
|---|---|---|
| EGNet | 0.672 | 0.087 |
| MirrorNet | 0.748 | 0.061 |
| PMDNet (ours) | 0.790 | 0.032 |
Evaluated on the PMD test split (571 images).
License
CC BY-NC 4.0 — non-commercial use only.
Citation
@INPROCEEDINGS{PMD:2020,
Author = {Jiaying Lin and Guodong Wang and Rynson W.H. Lau},
Title = {Progressive Mirror Detection},
Booktitle = {Proc. CVPR},
Year = {2020}
}