More with Less: a Large Scale Remote Sensing VLM with a Simple Recipe

Computer Vision and Pattern RecognitionMachine Learning

Summary

The authors show that special remote sensing model designs are not always needed to get good results with vision-language models (VLMs) on Earth Observation tasks. Instead, they train a general model on lots of different remote sensing data and tasks using reinforcement learning to handle both text answers and image segmentations. Their approach performs well across many challenging benchmarks involving various image types and tasks. They find that increasing the diversity and amount of training data improves performance more than creating new model architectures.

Authors

Stefan Maria Ailuro, Mario Markov, Mohammad Mahdi, Luc Van Gool, Danda Pani Paudel

Abstract

Remote sensing vision-language models are increasingly expected to support open-ended reasoning over Earth Observation data and a variety of tasks. Most recent progress in this area has been driven by remote-sensing-specific architectural designs, often introducing new encoders, alignment modules, or task-specific fusion mechanisms. In this work, we challenge the necessity of such architectural specialization. We show that a generally capable vision-language model can achieve competitive or state-of-the-art performance at challenging remote sensing benchmarks, provided that it is trained at sufficient scale across diverse data and tasks. Our model uses a single language policy that can either answer directly in text or invoke a localization tool for segmentation and grounding. To train this heterogeneous behaviour, we employ a multi-task reinforcement learning framework with adaptive task rewards covering multiple-choice VQA, free-form VQA, captioning, detection, and segmentation across a large variety of input types. Our approach achieves competitive results across a broad set of benchmarks, including high-resolution, multi-temporal, multi-modal and multi-view tasks. Further, as training data scales, our experiments show consistent improvements across most tasks both in and out of distribution, which correlate with per-task data diversity. These findings suggest that, for remote sensing VLMs, data scale is more important than architectural novelty.