Calibrated Out-of-Distribution Detection with a Generic Representation (GROOD)

PyTorch implementation of our work on Out-of-Distribution (OOD) image detection using a generic pre-trained models.

[Paper]

Abstract: Out-of-distribution detection is a common issue in deploying vision models in practice and solving it is an essential building block in safety critical applications. Existing OOD detection solutions focus on improving the OOD robustness of a classification model trained exclusively on in-distribution (ID) data. In this work, we take a different approach and propose to leverage generic pre-trained representations. We first investigate the behaviour of simple classifiers built on top of such representations and show striking performance gains compared to the ID trained representations. We propose a novel OOD method, called GROOD, that achieves excellent performance, predicated by the use of a good generic representation. Only a trivial training process is required for adapting GROOD to a particular problem. The method is simple, general, efficient, calibrated and with only a few hyper-parameters. The method achieves state-of-the-art performance on a number of OOD benchmarks, reaching near perfect performance on several of them.

Pre-trained Representation models

In the arXiv paper we used CLIP. It needs to be installed before running the training (follow the link for the installation instructions). However, other open-source models can be used, such as OpenCLIP or DIHT.

Datasets preparation

You need to download manually these datasets:

• LSUN from LSUN webpage
• texture, places365 and inaturalist are from OpenOOD (clone the repo to ./_data/OpenOOD/; cd to it; and use the OpenOOD/scripts/download/dowanload.sh script)
• ssb_cub, ssb_scars and ssb_aircraft are from SemanticShiftBenchmark (put them into the e.g. ./_data/SemanticShiftBenchmark/ + FGVC-Aircraft, ...). You will need to run the scripts from dataloaders/builders/ssb to convert the data to the format accepted by our data loaders.
• The DomainNet dataset M3SDA, i.e. "clipart", "infograph", "painting", "quickdraw", "real" and "sketch", was obtained from the M3SDA webpages (put them into the ./_data/M3SDA/ directory)

Other datasets will be downloaded automatically from torchvision when used for the first time (CIFAR10, SVHN, CIFAR100, TinyImageNet, MNIST).

Experiments

To generate the results in the paper run the following scripts: (by default, all experiments and results will be saved in ./_out/ directory. It can be changed in the respective script files.)

First add the repository to the python path (execute from the repository root dir):

export PYTHONPATH=`pwd`

Table 2 - semantic shift only.

./eval/scripts/run_all_6v4.sh <my_method> <config_file> <gpu_id> <eval_type>

where:

• <my_method> is the method name and the results will be in the directory with the same name
• <config_file> config file from the ./config/ directory, e.g. clip_L14.yaml or it can be None for evaluation only (skipping training of models)
• <gpu_id> which gpu to use (e.g. 0)
• <eval_type> what evaluation type to use, e.g. grood or linprobe (for linear probe only) Available evaluation types are in ./eval/utils.py at eval_switcher function.

Table 3 - mixed semantic and domain shifts first train the model:

CUDA_VISIBLE_DEVICES=0 python train.py --config ./config/<config_file> EXPERIMENT.NAME <my_method>

then evaluate:

./eval/scripts/run_all_ood.sh ./_out/experiments/<my_method> <gpu_id> <eval_type>

Table 4 - semantic shift (Real-B column) and domain shift only (next four columns)

./eval/scripts/run_shift_all.sh <my_method> <config_file> <gpu_id> <eval_type>"

Table 5 - fine-grained semantic shift

./eval/scripts/run_all_ssb.sh <my_method> <config_file> <gpu_id> <eval_type> <skip_trainig>

where:

• <skip_trainig> set to "no" to run training + evaluation or to anything else for evaluation only

Plots and examples in jupyter notebooks

See the notebooks in ./jupyter/ folder for the following visualizations:

Figure 1 - Complementarity of the LP and NM classifiers

Figure 3 - Visualization of the GROOD decision making wrt. ID-data

Bibtex

If you use this work please cite:

@InProceedings{Vojir_2023_ICCV,
    author    = {Voj{\'\i}\v{r}, Tom\'a\v{s} and \v{S}ochman, Jan and Aljundi, Rahaf and Matas, Ji\v{r}{\'\i}},
    title     = {Calibrated Out-of-Distribution Detection with a Generic Representation},
    booktitle = {Proceedings of the IEEE/CVF International Conference on Computer Vision (ICCV) Workshops},
    month     = {October},
    year      = {2023},
    pages     = {4507-4516}
}

Licence

Copyright (c) 2021 Toyota Motor Europe
Patent Pending. All rights reserved.

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License