Industrial KNN-based Anomaly Detection

⭐Now has streamlit support!⭐ Run $ streamlit run streamlit_app.py

This repo aims to reproduce the results of the following KNN-based anomaly detection methods:

1. SPADE (Cohen et al. 2021) - knn in z-space and distance to feature maps
2. PaDiM* (Defard et al. 2020) - distance to multivariate Gaussian of feature maps
3. PatchCore (Roth et al. 2021) - knn distance to avgpooled feature maps

* actually does not have any knn mechanism, but shares many things implementation-wise.

---

Install

$ pipenv install -r requirements.txt

Usage

CLI:

$ python indad/run.py METHOD [--dataset DATASET]

Results can be found under ./results/.

Code example:

from indad.model import SPADE

model = SPADE(k=5, backbone_name="resnet18")

# feed healthy dataset
model.fit(...)

# get predictions
img_lvl_anom_score, pxl_lvl_anom_score = model.predict(...)

Custom datasets

👁️

Check out one of the downloaded MVTec datasets. Naming of images should correspond among folders. Right now there is no support for no ground truth pixel masks.

📂datasets
 ┗ 📂your_custom_dataset
  ┣ 📂 ground_truth/defective
  ┃ ┣ 📂 defect_type_1
  ┃ ┗ 📂 defect_type_2
  ┣ 📂 test
  ┃ ┣ 📂 defect_type_1
  ┃ ┣ 📂 defect_type_2
  ┃ ┗ 📂 good
  ┗ 📂 train/good

$ python indad/run.py METHOD --dataset your_custom_dataset

---

Results

📝 = paper, 👇 = this repo

Image-level

class	SPADE 📝	SPADE 👇	PaDiM 📝	PaDiM 👇	PatchCore 📝	PatchCore 👇
bottle	-	98.8	98.3	99.8	■100.0■	■100.0■
cable	-	76.5	96.7	93.3	■99.5■	96.2
capsule	-	84.6	■98.5■	88.3	98.1	95.3
carpet	-	84.3	99.1	■99.4	98.7	98.7
grid	-	37.1	97.3	98.2	■98.2■	93.0
hazelnut	-	88.7	98.2	83.7	■100.0■	100.0
leather	-	97.1	99.2	99.9	■100.0■	100.0
metal_nut	-	74.6	97.2	99.4	■100.0■	98.3
pill	-	72.6	95.7	89.0	■96.6■	92.8
screw	-	53.1	■98.5■	83.0	98.1	96.7
tile	-	97.8	94.1	98.6	98.7	■99.0■
toothbrush	-	89.4	98.8	97.2	■100.0■	98.1
transistor	-	89.2	97.5	96.8	■100.0■	99.7
wood	-	98.3	94.7	98.9	■99.2■	98.8
zipper	-	96.7	98.5	89.5	■99.4■	98.4
averages	85.5	82.6	97.5	94.3	■99.1■	97.7

Pixel-level

class	SPADE 📝	SPADE 👇	PaDiM 📝	PaDiM 👇	PatchCore 📝	PatchCore 👇
bottle	97.5	97.7	94.8	97.8	■98.6■	97.8
cable	93.7	94.3	88.8	96.1	■98.5■	97.4
capsule	97.6	98.6	93.5	98.3	■98.9■	98.3
carpet	87.4	99.0	96.2	98.6	■99.1■	98.3
grid	88.5	96.1	94.6	97.2	■98.7■	96.7
hazelnut	98.4	98.1	92.6	97.5	■98.7■	98.1
leather	97.2	99.2	97.8	98.7	■99.3■	98.4
metal_nut	■99.0■	96.1	85.6	96.5	98.4	96.2
pill	■99.1■	93.5	92.7	93.2	97.6	98.7
screw	98.1	98.9	94.4	97.8	■99.4■	98.4
tile	■96.5■	93.3	86.0	94.8	95.9	94.0
toothbrush	■98.9■	■98.9■	93.1	98.3	98.7	98.1
transistor	■97.9■	96.3	84.5	97.2	96.4	97.5
wood	94.1	94.4	91.1	93.6	■95.1■	91.9
zipper	96.5	98.2	95.9	97.4	■98.9■	97.6
averages	96.9	96.8	92.1	96.9	■98.1■	97.2

PatchCore-10 was used.

Hyperparams

The following parameters were used to calculate the results. They more or less correspond to the parameters used in the papers.

spade:
  backbone: wide_resnet50_2
  k: 50
padim:
  backbone: wide_resnet50_2
  d_reduced: 250
  epsilon: 0.04
patchcore:
  backbone: wide_resnet50_2
  f_coreset: 0.1
  n_reweight: 3

---

Progress

• Datasets
• Code skeleton
• Config files
• CLI
• Logging
• SPADE
• PADIM
• PatchCore
• Add custom dataset option
• Add dataset progress bar
• Add schematics
• Unit tests

Design considerations

• Data is processed in single images to avoid batch statistics interference.
• I decided to implement greedy kcenter from scratch and there is room for improvement.
• torch.nn.AdaptiveAvgPool2d for feature map resizing, torch.nn.functional.interpolate for score map resizing.
• GPU is used for backbones and coreset selection. GPU coreset selection currently runs at:
  • 400-500 it/s @ float32 (RTX3080)
  • 1000+ it/s @ float16 (RTX3080)

---

Acknowledgements

• hcw-00 for tipping sklearn.random_projection.SparseRandomProjection.
• h1day for adding a custom range to the streamlit app.

References

SPADE:

@misc{cohen2021subimage,
      title={Sub-Image Anomaly Detection with Deep Pyramid Correspondences}, 
      author={Niv Cohen and Yedid Hoshen},
      year={2021},
      eprint={2005.02357},
      archivePrefix={arXiv},
      primaryClass={cs.CV}
}

PaDiM:

@misc{defard2020padim,
      title={PaDiM: a Patch Distribution Modeling Framework for Anomaly Detection and Localization}, 
      author={Thomas Defard and Aleksandr Setkov and Angelique Loesch and Romaric Audigier},
      year={2020},
      eprint={2011.08785},
      archivePrefix={arXiv},
      primaryClass={cs.CV}
}

PatchCore:

@misc{roth2021total,
      title={Towards Total Recall in Industrial Anomaly Detection}, 
      author={Karsten Roth and Latha Pemula and Joaquin Zepeda and Bernhard Schölkopf and Thomas Brox and Peter Gehler},
      year={2021},
      eprint={2106.08265},
      archivePrefix={arXiv},
      primaryClass={cs.CV}
}