This repository contains the supplementary Python code for paper "Background Data Resampling for Outlier-Aware Classification" to appear at CVPR 2020.

Prerequisites

Environment

The code was tested with Python 3.7+ using PyTorch v1.2+. Additional Python libraries may be required, as specified in requirements.txt.

Datasets

The pre-training and evaluation code makes use of the following datasets:

Dataset	URL
CIFAR-10/100	https://www.cs.toronto.edu/~kriz/cifar.html
Tiny ImageNet	https://tiny-imagenet.herokuapp.com/
Textures	https://www.robots.ox.ac.uk/~vgg/data/dtd/
LSUN	https://www.yf.io/p/lsun
SVHN	http://ufldl.stanford.edu/housenumbers/
Places	http://places.csail.mit.edu/

Training with background data further requires ILSVRC'12 and/or Tiny Images:

Dataset	URL
ILSVRC 2012	http://www.image-net.org/challenges/LSVRC/2012/
80M Tiny Images	https://groups.csail.mit.edu/vision/TinyImages/

All datasets must be downloaded and prepared under paths specified in datasets/__init__.py. ILSVRC'12 data should be further processed into LMDB format for faster data loading.

Instructions

Pre-training

Use train.py to pretrain models on the in-distribution datasets. Models are automatically saved under checkpoints/ folder. Example:

python train.py --gpus 0 -a wrn40 -d cifar10 --epochs 100

OOD detection

Use test_ood.py to evaluate OOD detection of trained models on one or more test sets. Example:

python test_ood.py --gpus 0 -a wrn40 -id cifar10 -od gaussian uniform textures lsun svhn places --out-ratio 0.2 --load-path path/to/model.pth

Fine-tuning with background data

Use train_bg.py to finetune models using background data. Supports full background dataset, uniformly subsampled background, or resampled background using learned weights. Example:

python train_bg.py --gpus 0 -a wrn40 -id cifar10 -od ilsvrc --epochs 50 --load-path path/to/model.pth
python train_bg.py --gpus 0 -a wrn40 -id cifar10 -od ilsvrc --epochs 50 --load-path path/to/model.pth --resample random -p 0.1
python train_bg.py --gpus 0 -a wrn40 -id cifar10 -od ilsvrc --epochs 50 --load-path path/to/model.pth --resample path/to/resample/weights.pth -p 0.1

Adversarial background resampling

Use train_bg_resample.py to perform adversarial resampling on background dataset. Resampling weights are automatically saved under checkpoints/ folder. Example:

python train_bg_resample.py --gpus 0 -a wrn40 -id cifar10 -od ilsvrc --epochs 50 --load-path path/to/model.pth