GPT Sonograpy: Hand Gesture Decoding from Forearm Ultrasound Images via VLM
Keshav Bimbraw, Ye Wang, Jing Liu, Toshiaki Koike-Akino
TL;DR
This work investigates whether a large vision-language model, GPT-4o, can decode hand gestures from forearm ultrasound images without fine-tuning. By encoding ultrasound frames as text and applying few-shot in-context learning, the authors show that GPT-4o achieves notable gesture classification accuracy, with within-session results reaching about 74% after 2 training examples and cross-session results around 61% with 3 examples. The study demonstrates the practical potential of LVLMs for medical imaging tasks where fine-tuning is costly, and it highlights the influence of prompts, reasoning capabilities, and input formats on performance. Overall, the results suggest that LVLMs can serve as effective, label-efficient tools for ultrasound-based gesture interpretation and human–machine interfaces, motivating further cross-subject validation and comparisons with retrieval-based and PEFT approaches.
Abstract
Large vision-language models (LVLMs), such as the Generative Pre-trained Transformer 4-omni (GPT-4o), are emerging multi-modal foundation models which have great potential as powerful artificial-intelligence (AI) assistance tools for a myriad of applications, including healthcare, industrial, and academic sectors. Although such foundation models perform well in a wide range of general tasks, their capability without fine-tuning is often limited in specialized tasks. However, full fine-tuning of large foundation models is challenging due to enormous computation/memory/dataset requirements. We show that GPT-4o can decode hand gestures from forearm ultrasound data even with no fine-tuning, and improves with few-shot, in-context learning.
