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arxiv: 2605.14091 · v2 · pith:IQUOJVRDnew · submitted 2026-05-13 · 💻 cs.CV

Venus-DeFakerOne: Unified Fake Image Detection & Localization

Pith reviewed 2026-05-15 05:25 UTC · model grok-4.3

classification 💻 cs.CV
keywords fake image detectionforgery localizationunified foundation modeldeepfake detectionAIGC detectioncross-domain artifactsInternVL2SAM2
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The pith

DeFakerOne integrates InternVL2 and SAM2 into one model that detects and localizes image forgeries across many generation types at once.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

Modern generative tools now produce forgeries that blend document edits, natural-image changes, deepfakes, and full AI synthesis, yet most detectors remain locked to one forgery family. DeFakerOne tackles the resulting mismatch by building a single foundation model that performs both whole-image detection and pixel-level localization. It does so by joining InternVL2 for semantic feature extraction with SAM2 for precise mask prediction, then training the pair under fine-grained supervision across many domains. Experiments show the combined system beats prior methods on 39 detection benchmarks and 9 localization benchmarks while holding up under real-world noise and newer generators. The work also maps how data volume, artifact overlap, and supervision granularity affect unified performance.

Core claim

DeFakerOne, formed by integrating InternVL2 and SAM2 with fine-grained supervision, supplies a unified foundation model that jointly detects image-level forgeries and localizes them at the pixel level, surpassing prior specialized methods on 39 detection benchmarks and 9 localization benchmarks while remaining robust to perturbations and advanced generators such as GPT-Image-2.

What carries the argument

DeFakerOne, the integration of InternVL2 for high-level vision-language features and SAM2 for segmentation masks, trained with fine-grained labels to model cross-domain artifact transfer and interference patterns.

If this is right

  • One model can replace the current set of domain-specific detectors for document, deepfake, and AIGC forgeries.
  • Scaling training data while preserving original-resolution artifacts improves both detection accuracy and localization precision.
  • Fine-grained supervision is required to disentangle interfering artifacts from different forgery sources.
  • The same architecture shows robustness against perturbations and against generators not seen during training.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The same integration pattern could be tested on video sequences by adding temporal consistency constraints to the segmentation branch.
  • The observed artifact-transfer patterns suggest a way to curate synthetic training sets that deliberately mix forgery types to improve generalization.
  • Content platforms could use the localization output to route suspicious regions to human reviewers rather than discarding entire images.

Load-bearing premise

That combining InternVL2 and SAM2 under fine-grained supervision is enough to learn forgery patterns that transfer across domains without needing separate models for each forgery type.

What would settle it

A new generator that creates realistic forgeries whose artifact patterns lie outside the current training distribution yet still produce images the model consistently fails to flag or localize on held-out tests.

read the original abstract

In recent years, the rapid evolution of generative AI has fundamentally reshaped the paradigm of image forgery, breaking the traditional boundaries between document editing, natural image manipulation, DeepFake generation, and full-image AIGC synthesis. Despite this shift toward unified forgery generation, existing research in Fake Image Detection and Localization (FIDL) remains fragmented. This creates a mismatch between increasingly unified forgery generation mechanisms and the domain-specific detection paradigm. Bridging this mismatch poses two key challenges for FIDL: understanding cross-domain artifacts transfer and interference, and building a high-capacity unified foundation model for joint detection and localization. To address these challenges, we propose DeFakerOne, a data-centric, unified FIDL foundation model integrating InternVL2 and SAM2. DeFakerOne enables simultaneous image-level detection and pixel-level forgery localization across diverse scenarios. Extensive experiments demonstrate that DeFakerOne achieves state-of-the-art performance, outperforming baselines on 39 forgery detection benchmarks and 9 localization benchmarks. Furthermore, the model exhibits superior robustness against real-world perturbations and state-of-the-art generators such as GPT-Image-2. Finally, we provide a systematic analysis of data scaling laws, cross-domain artifacts transfer-interference patterns, the necessity of fine-grained supervision, and the original resolution artifacts preservation, highlighting the design principles for scalable, robust, and unified FIDL.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 1 minor

Summary. The manuscript presents DeFakerOne, a data-centric unified foundation model for Fake Image Detection and Localization (FIDL) that integrates InternVL2 and SAM2 with fine-grained supervision. It claims to simultaneously perform image-level detection and pixel-level localization across diverse forgery types, achieving SOTA results by outperforming baselines on 39 detection benchmarks and 9 localization benchmarks, while also demonstrating robustness to perturbations and new generators such as GPT-Image-2, and providing analyses of data scaling laws, cross-domain artifact transfer-interference, and the role of fine-grained supervision.

Significance. If the performance claims and analyses are substantiated with rigorous evidence, the work would be significant for computer vision by addressing the mismatch between unified generative forgery mechanisms and prior domain-specific FIDL methods, potentially providing a scalable foundation model that captures cross-domain artifacts and sets new standards for joint detection-localization tasks.

major comments (2)
  1. [Abstract] Abstract: The assertion that DeFakerOne 'achieves state-of-the-art performance, outperforming baselines on 39 forgery detection benchmarks and 9 localization benchmarks' supplies no quantitative metrics, error bars, dataset details, or references to specific tables/figures, leaving the central empirical claims unsupported by visible evidence.
  2. [Abstract] Abstract / Experiments (implied): No ablation studies are described that isolate the contribution of the proposed unification, joint architecture, or fine-grained supervision from the scale and pre-training of the frozen InternVL2+SAM2 base models; without this, gains cannot be attributed to the data-centric design rather than parameter count.
minor comments (1)
  1. [Abstract] Title vs. Abstract: The title uses 'Venus-DeFakerOne' while the body refers only to 'DeFakerOne'; standardize the model name for consistency.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the constructive feedback, which helps clarify the presentation of our empirical claims. We have revised the manuscript to address both major comments by strengthening the abstract and adding explicit ablation studies.

read point-by-point responses
  1. Referee: [Abstract] Abstract: The assertion that DeFakerOne 'achieves state-of-the-art performance, outperforming baselines on 39 forgery detection benchmarks and 9 localization benchmarks' supplies no quantitative metrics, error bars, dataset details, or references to specific tables/figures, leaving the central empirical claims unsupported by visible evidence.

    Authors: We agree that the abstract would benefit from explicit pointers to the supporting evidence. In the revised version, we have updated the abstract to reference the primary results tables (Tables 1-2 for the 39 detection benchmarks and Tables 3-4 for the 9 localization benchmarks), where the quantitative metrics, dataset details, and baseline comparisons are reported. Error bars from repeated runs on key benchmarks are included in the supplementary material. This ensures the central claims are directly supported by visible evidence in the manuscript. revision: yes

  2. Referee: [Abstract] Abstract / Experiments (implied): No ablation studies are described that isolate the contribution of the proposed unification, joint architecture, or fine-grained supervision from the scale and pre-training of the frozen InternVL2+SAM2 base models; without this, gains cannot be attributed to the data-centric design rather than parameter count.

    Authors: We acknowledge this valid point regarding attribution. Although the base models are frozen, we have added a dedicated ablation study in the revised manuscript (new Section 4.3 and Table 5) that compares the full DeFakerOne model against variants using only the frozen InternVL2+SAM2 backbones without our unified training data or fine-grained supervision. These results demonstrate that the performance improvements stem from the data-centric unification and supervision strategy rather than base model scale alone. revision: yes

Circularity Check

0 steps flagged

No circularity; empirical SOTA claims rest on external benchmarks

full rationale

The paper proposes DeFakerOne by integrating existing models (InternVL2 and SAM2) with fine-grained supervision and reports performance on 39 detection and 9 localization benchmarks. No equations, derivations, fitted parameters renamed as predictions, or self-citation load-bearing steps appear. Central claims are validated against independent external benchmarks rather than reducing to inputs by construction. This is a standard empirical ML paper with self-contained experimental validation.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Abstract-only review yields no explicit free parameters, axioms, or invented entities; the approach relies on standard integration of two pre-trained foundation models plus fine-grained supervision whose details are not provided.

pith-pipeline@v0.9.0 · 5529 in / 1006 out tokens · 38291 ms · 2026-05-15T05:25:41.568710+00:00 · methodology

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