Realistic Unsupervised CLIP Fine-tuning with Universal Entropy Optimization

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Liang, Jian, Sheng, Lijun, Wang, Zhengbo, He, Ran, Tan, Tieniu
Formato: Preprint
Publicado: 2023
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866910532522475520
author Liang, Jian
Sheng, Lijun
Wang, Zhengbo
He, Ran
Tan, Tieniu
author_facet Liang, Jian
Sheng, Lijun
Wang, Zhengbo
He, Ran
Tan, Tieniu
contents The emergence of vision-language models, such as CLIP, has spurred a significant research effort towards their application for downstream supervised learning tasks. Although some previous studies have explored the unsupervised fine-tuning of CLIP, they often rely on prior knowledge in the form of class names associated with ground truth labels. This paper explores a realistic unsupervised fine-tuning scenario, considering the presence of out-of-distribution samples from unknown classes within the unlabeled data. In particular, we focus on simultaneously enhancing out-of-distribution detection and the recognition of instances associated with known classes. To tackle this problem, we present a simple, efficient, and effective approach called Universal Entropy Optimization (UEO). UEO leverages sample-level confidence to approximately minimize the conditional entropy of confident instances and maximize the marginal entropy of less confident instances. Apart from optimizing the textual prompt, UEO incorporates optimization of channel-wise affine transformations within the visual branch of CLIP. Extensive experiments across 15 domains and 4 different types of prior knowledge validate the effectiveness of UEO compared to baseline methods. The code is publicly available at \url{https://github.com/tim-learn/UEO}.
format Preprint
id arxiv_https___arxiv_org_abs_2308_12919
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Realistic Unsupervised CLIP Fine-tuning with Universal Entropy Optimization
Liang, Jian
Sheng, Lijun
Wang, Zhengbo
He, Ran
Tan, Tieniu
Computer Vision and Pattern Recognition
Machine Learning
The emergence of vision-language models, such as CLIP, has spurred a significant research effort towards their application for downstream supervised learning tasks. Although some previous studies have explored the unsupervised fine-tuning of CLIP, they often rely on prior knowledge in the form of class names associated with ground truth labels. This paper explores a realistic unsupervised fine-tuning scenario, considering the presence of out-of-distribution samples from unknown classes within the unlabeled data. In particular, we focus on simultaneously enhancing out-of-distribution detection and the recognition of instances associated with known classes. To tackle this problem, we present a simple, efficient, and effective approach called Universal Entropy Optimization (UEO). UEO leverages sample-level confidence to approximately minimize the conditional entropy of confident instances and maximize the marginal entropy of less confident instances. Apart from optimizing the textual prompt, UEO incorporates optimization of channel-wise affine transformations within the visual branch of CLIP. Extensive experiments across 15 domains and 4 different types of prior knowledge validate the effectiveness of UEO compared to baseline methods. The code is publicly available at \url{https://github.com/tim-learn/UEO}.
title Realistic Unsupervised CLIP Fine-tuning with Universal Entropy Optimization
topic Computer Vision and Pattern Recognition
Machine Learning
url https://arxiv.org/abs/2308.12919