We propose DINO-FIL, a transformer-based framework for pixel-level localization of generative image forgeries. The method leverages multi-layer representations from a pretrained DINOv3 ViT-H+/16 encoder combined with a lightweight fusion decoder to capture both semantic structure and fine-grained texture inconsistencies introduced by image editing. By aggregating intermediate transformer features across depths, the model improves sensitivity to subtle, spatially localized artifacts that are often missed by standard single-layer approaches. We evaluate DINO-FIL in a cross-dataset setting, training on B-Free and testing on Beyond the Brush, CocoGlide, TGIF, and SAGI-D. The model achieves strong generalization, outperforming existing baselines on average and on four of five evaluated datasets, while maintaining a high true negative rate on pristine images.
Figures & tables
Figure 1: Overview of DINO-FIL. The batch of resized images is encoded with DINOv3, and hidden states from layers 8,16,24, and 32 are converted into spatial patch maps fℓ by reshaping and discarding one CLS token and four register tokens. The projection adapter maps fℓ to pℓ∈RB×Cd×q×q . The context block produces gℓ∈RB×Cd×q×q using lightweight multi-scale depthwise-separable convolutions. Before fusion, gℓ is optionally regularized with spatial dropout, yielding g~ℓ during training and the identity mapping otherwise. The resulting g~ℓ maps are fused by a horizontal depth-wise top-down decoder on the fixed q×q patch grid. A 1×1 prediction head produces patch-level logits, which are upsampled and passed through a sigmoid to obtain the final inpainting probability mask. Here, q=S/P , P=16 , Cb=1280 , and Cd=1024 .
Test image resolution
Unfrozen layers
BtB
CocoGlide
TGIF
SAGI-D
B-Free
Average
IoU
F1
IoU
F1
IoU
F1
IoU
F1
IoU
F1
IoU
F1
512px
0
0.23
0.31
0.75
0.82
0.27
0.33
0.47
0.55
0.82
0.89
0.51
0.58
6
0.33
0.41
0.77
0.85
0.38
0.45
0.52
0.61
0.86
0.92
0.57
0.65
12
0.36
0.44
0.81
0.87
0.38
0.44
0.58
0.66
0.89
0.94
0.60
0.67
16
0.36
0.43
0.83
0.88
0.38
0.43
0.59
0.67
0.90
0.94
0.61
0.67
24
0.32
0.38
0.84
0.89
0.33
0.37
0.57
0.64
0.91
0.95
0.60
0.65
Table 1: Comparison of DINO-FIL variants under different numbers of unfrozen encoder layers and test image resolutions (training resolution is fixed at 512px), evaluated using average pixel-level IoU and F1 score on image forgery localization. The best results are shown in bold, and the second-best results are underlined.
Model
BtB
CocoGlide
TGIF
SAGI-D
B-Free
Average
IoU
F1
IoU
F1
IoU
F1
IoU
F1
IoU
F1
IoU
F1
DINO-FIL (ours)
0.59
0.68
0.87
0.92
0.57
0.63
0.66
0.73
0.87
0.92
0.71
0.77
DinoLizer
0.42
0.56
0.57
0.69
0.39
0.49
0.38
0.49
0.70
0.81
0.49
0.61
TruFor
0.22
0.30
0.29
0.36
0.70
0.80
0.35
0.41
0.22
0.30
0.36
0.43
Table 2: Comparison of DINO-FIL (ours) with DinoLizer and TruFor, the two strongest-performing methods reported in the DinoLizer benchmark [ 2 ] . Performance is reported using average pixel-level IoU and F1 score for image forgery localization. The SAGI-D results for DinoLizer and TruFor are computed as image-count-weighted averages of the reported SAGI-SP and SAGI-FR results. The best results are shown in bold, and the second-best results are underlined.
Dataset
Number of Images
Pixel-level FP Rate
Image-level TN Rate
COCO
2,922
0.0019
0.9767
Open Images
5,579
0.0040
0.9684
RAISE
580
0.0021
0.9810
Average
9,081
0.0032
0.9719
Table 3: False-positive evaluation of DINO-FIL on original, non-manipulated images. We report the pixel-level false-positive rate and the image-level true-negative rate. The average is computed over all images across the three datasets.
Train Resolution
Test Resolution
Beyond the Brush
TGIF
SAGI-D
Average
IoU
F1
IoU
F1
IoU
F1
IoU
F1
512px
512px
0.37
0.44
0.41
0.44
0.76
0.81
0.51
0.56
1024px
0.68
0.76
0.62
0.69
0.83
0.88
0.71
0.78
1024px
1024px
0.64
0.71
0.55
0.62
0.84
0.88
0.68
0.74
Table 4: Comparison of DINO-FIL variants trained at different resolutions (512px and 1024px) and evaluated at corresponding test resolutions for image forgery localization. Performance is reported in terms of average pixel-level IoU and F1 score across datasets. The best results are shown in bold, and the second-best results are underlined.
Recent advancements in generative AI have led to image editing models capable of producing realistic forgeries that evade traditional image forgery localization methods, as these approaches depend on physical noise absent in synthetic data. To address this challenge, we theoretically demonstrate that the diffusion process inherently suppresses local high-frequency variance, creating a statistical energy gap that is distinguishable from the natural entropy of optical imaging. Guided by this insight, we propose FLAME, a unified framework that utilizes a LAD map to capture these intrinsic anomalies, coupled with a parameter-efficient adapter for SAM to achieve precise, pixel-level forgery localization. Furthermore, to bridge the lag between forensic benchmarks and evolving generative models, we introduce EditStream, an automated pipeline for continuous, instruction-based training data synthesis. Extensive experiments demonstrate that FLAME establishes a new state-of-the-art, significantly outperforming previous methods on AI-generated forgery datasets while effectively generalizing to unseen generative architectures. Our code is available at https://github.com/phoenixnir/FLAME.
Modern diffusion-based inpainting models pose significant challenges for image forgery localization (IFL), as their full regeneration pipelines reconstruct the entire image via a latent decoder, disrupting the camera-level noise patterns that existing forensic methods rely on. We propose DiffusionPrint, a patch-level contrastive learning framework that learns a forensic signal robust to the spectral distortions introduced by latent decoding. It exploits the fact that inpainted regions generated by the same model share a consistent generative fingerprint, using this as a self-supervisory signal. DiffusionPrint trains a convolutional backbone via a MoCo-style objective with cross-category hard negative mining and a generator-aware classification head, producing a forensic feature map that serves as a highly discriminative secondary modality in fusion-based IFL frameworks. Integrated into TruFor, MMFusion, and a lightweight fusion baseline, DiffusionPrint consistently improves localization across multiple generative models, with gains of up to +28% on mask types unseen during fine-tuning and confirmed generalization to unseen generative architectures. Code is available at https://github.com/mever-team/diffusionprint
Diffusion-based inpainting models modify only a localized part of an image, while many AI-image detectors rely on global artifacts and do not localize. These artifacts vary across generators, limiting detector transfer under distribution shifts. Recent work shows that restoring the authentic pixels outside the inpainted region removes these cues and can degrade pretrained detectors. To address this, we present FUSED, a unified framework for the joint detection and localization of AI-generated inpainting. FUSED combines low-level forensic cues with high-level semantic features using a sparsely-gated Mixture-of-Experts architecture, enabling the model to adaptively prioritize the most relevant signal for each token. For each input, FUSED predicts both an image-level manipulation score and a pixel-level mask of the inpainted area. On the OpenSDID cross-generator benchmark, FUSED achieves the best average detection and localization, with the largest gains on unseen generators. The same model transfers directly to the held-out AutoSplice and CocoGlide benchmarks, more than doubling localization performance. Evaluating each held-out benchmark with and without the global generator artifact further shows that all evaluated methods, ours included, partly read the artifact as evidence of manipulation, and FUSED remains the strongest under both conditions. Code and pretrained models are available at https://github.com/AntonNuzhdin/FUSED.
Anton Nuzhdin, Marcel Worring, Ivona Najdenkoska
Informatics Institute, University of Amsterdam Amsterdam, The Netherlands