# Revisiting Change VQA in Remote Sensing with Structured and Native Multimodal Qwen Models

Source: [Revisiting Change VQA in Remote Sensing with Structured and Native Multimodal Qwen Models](<https://www.sota2.com/research/paper/69e705297d0172140ec7f32a>)

Collection index: [llms.txt](<https://www.sota2.com/research/llms.txt>)

Data updated: 2026-04-22T05:23:53.567Z

Authors: Yakoub Bazi, Mohamad M. Al Rahhal, Mansour Zuair, Faroun Mohamed

Published: 2026-04-20T15:47:52.000Z

## Abstract

Change visual question answering (Change VQA) addresses the problem of answering natural-language questions about semantic changes between bi-temporal remote sensing (RS) images. Although vision-language models (VLMs) have recently been studied for temporal RS image understanding, Change VQA remains underexplored in the context of modern multimodal models. In this letter, we revisit the CDVQA benchmark using recent Qwen models under a unified low-rank adaptation (LoRA) setting. We compare Qwen3-VL, which follows a structured vision-language pipeline with multi-depth visual conditioning and a full-attention decoder, with Qwen3.5, a native multimodal model that combines a single-stage alignment with a hybrid decoder backbone. Experimental results on the official CDVQA test splits show that recent VLMs improve over earlier specialized baselines. They further show that performance does not scale monotonically with model size, and that native multimodal models are more effective than structured vision-language pipelines for this task. These findings indicate that tightly integrated multimodal backbones contribute more to performance than scale or explicit multi-depth visual conditioning for language-driven semantic change reasoning in RS imagery.

## Recorded benchmark results

A research result applies to its stated dataset, split, metric and evaluation configuration. Compare like-for-like settings, preserve the metric's unit and direction, and distinguish paper-reported results from independent reproduction. The best result recorded here is not a claim of exhaustive, current global coverage.

- [Change Visual Question Answering on CDVQA (test 1)](<https://www.sota2.com/research/sota/change-visual-question-answering-on-cdvqa-test-1.md>): Change Visual Question Answering; CDVQA (test 1); AA: 68.59.

- [Change Visual Question Answering on CDVQA (test2)](<https://www.sota2.com/research/sota/change-visual-question-answering-on-cdvqa-test2.md>): Change Visual Question Answering; CDVQA (test2); AA: 69.56.

## Original sources and implementation

[Original paper](<https://arxiv.org/abs/2604.18429>)

[PDF](<https://arxiv.org/pdf/2604.18429.pdf>)