ACTIVE TEST TIME PROMPT LEARNING IN VISION- LANGUAGE MODELS

Dhruv Sarkar, Aprameyo Chakrabartty, Bibhudatta Bhanja, Abir Das

Keywords: Vision-Language Models, Prompt Learning, Active Learning, Test-Time Adaptation

Abstract: Test Time Optimisation is a setting where a model is made to learn new parameters on-the-fly during inference with the help of those very samples it is supposed to be tested on. Learning prompts at test time to improve the performance of Vision Language Models(VLMs) in downstream tasks has become a popular setting in recent times. In this paper, we propose a new framework for the Test Time Prompt Tuning in Pre-trained VLMs which incorporates actively sampled labels in the learning process to improve the performance of the model in downstream test-time settings. Our problem setting is underexplored yet well-motivated by considerations such as performance, efficiency and real-life applicability. Active Learning can be especially beneficial in the test-time setting in providing the option to query the true label when the model is uncertain in a real-life scenario and Prompt Tuning provides the advantage due to parameter efficiency. Our method is guided by these two principles and successfully combines the two to come up with a test-time optimisation scheme that is evaluated to be an improvement over existing methods under a fair evaluation protocol. We conduct experiments across 10 cross-dataset transfer datasets and 4 domain-generalisation datasets to show consistent improvement over the state-of-the-art.

Primary Area: applications to computer vision, audio, language, and other modalities

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Submission Number: 7985