Skip to content
Preprint

When Diffusion Models Forget Who You Are: Identity Preservation in Face Inpainting under Large Occlusions

Aug 2026 · 0 citations · 51 references
Computer Science

Abstract

Face inpainting with diffusion models has recently achieved impressive visual quality, yet preserving identity fidelity under significant occlusion and conflicting text guidance remains a major challenge. To address this issue, we present Reference Semantic Inpainting for Face (ReSem-Face), a cascaded diffusion framework that introduces an explicit identity-conditioned semantic prior for multi-reference face inpainting. Our approach distills representative identity features from multiple references to reconstruct missing semantic regions, which then guide the diffusion process through a multi-stream conditioning architecture. This design provides strong semantic constraints when pixels are absent and stabilizes identity reconstruction while remaining compatible with prompt-driven edits. Experiments on CelebAHQ-IDI-5 and VGGFace2 demonstrate that ReSem-Face yields more reliable identity-preserving completion under severe semantic masks and improves text-controlled editing quality compared with representative baselines.

View source

Similar papers

Jul 2026

Multi-condition guided diffusion model for face sketch-to-photo synthesis.

A diffusion-based framework with a stage-wise multi-condition guidance mechanism that enhances both structural and textural fidelity and compares with recent image-to-image translation and diffusion-based baselines to observe competitive performance in both visual coherence and identity preservation.

Yue Que, Xuegui Cheng, Shuqian Shi et al. · 0 citations
Preprint Jul 2026

Diff-ID: Identity Consistent Facial Image Generation and Morphing via Diffusion Models

Generative diffusion models have revolutionized facial image synthesis, yet robust identity preservation in high resolution outputs remains a critical challenge. This issue is especially vital for security systems, biometric authentication, and privacy sensitive applications, where any drift in identity integrity can undermine trust and functionality. We introduce Diff-ID, a diffusion based framework that enforces identity consistency while delivering photorealistic quality. Central to our approach is a custom 210K image dataset synthesized from CelebA-HQ, FFHQ, and LAION-Face and captioned via a fine tuned BLIP model to bolster identity awareness during training. Diff-ID integrates ArcFace and CLIP embeddings through a dual cross attention adapter within a fine tuned Stable Diffusion UNet. To further reinforce identity fidelity, we propose a pseudo discriminator loss based on ArcFace cosine similarity with exponential timestep weighting. Experiments on held out and unseen faces show that Diff-ID does not exceed InstantID in raw ArcFace Face Similarity, but achieves substantially lower FID and the strongest FIQ based identity--realism trade off among the evaluated methods. We also present a unified DDIM based morphing pipeline that enables qualitative facial interpolation without per identity fine tuning. We further argue that identity preservation and photorealism should be evaluated jointly rather than in isolation, as high identity similarity alone does not guarantee realistic outputs. To make this trade off explicit, we report Face Image Quality (FIQ) as a complementary ratio based score that combines identity similarity and perceptual realism while keeping FS and FID as the primary metrics.

T. Rizwan, Sara Atito, Muhammad Awais et al. · 0 citations
Preprint Jul 2026

ViDS: Video Diffusion Shader using 3D Face Tracking

We introduce ViDS, a Video Diffusion Shader that leverages 3D face tracking for expressive and identity-preserving portrait animation. We first reconstruct the identity-specific 3DMM mesh from the reference image, and then animate it using expression and pose parameters from a driving video. Leveraging dense geometric cues from 3DMM normal maps, we employ a video diffusion model as a neural shader to synthesize lifelike portrait animations while preserving the appearance and identity of the reference image. We find that more accurate 3DMM tracking enables finer-grained expression control. We also introduce an autoregressive diffusion sampling process that extends generation beyond the model's native window while reducing discontinuities between adjacent clips. Compared with prior diffusion-based approaches for portrait animation that rely on landmark-based conditioning or implicit motion latents, our method achieves more detailed and consistent expression and pose control while faithfully preserving identity and appearance. Detailed ablation studies validate the effectiveness of our design choices. Project page: https://fusheng-ji.github.io/ViDS/

Wenbo Ji, Davide Davoli, Zhe Chen et al. · 0 citations
Preprint Jul 2026

Image Inpainting via Stochastic Dynamics

Image inpainting aims to recover missing regions while preserving structural consistency. We propose a non-parametric method without network training based on data-guided stochastic dynamics. Starting from a masked image, the missing pixels are evolved through a reverse-time stochastic differential equation with a kernel-weighted correction estimated directly from a reference dataset. This empirical correction guides the reconstruction toward high-density regions of the data distribution without training a neural network or fitting a parametric density model. Experiments on MNIST, Fashion-MNIST, and MVTec show that the proposed method outperforms Mean Fill, Telea, and Navier-Stokes inpainting in PSNR, SSIM, and visual quality. On CelebA, it remains competitive and produces plausible completions for structure-sensitive occlusions. These results demonstrate the effectiveness of empirical reference statistics as a non-parametric prior for image inpainting.

Jiaqi Kuang, Zihao Guo, Zhongmin Qian · 0 citations
Aug 2026

RestoreGait: a recognition-oriented temporal inpainting framework for occluded gait recognition

Gait recognition represents a nonintrusive biometric modality that suffers from substantial performance degradation when subjected to real-world occlusions, such as those caused by bushes, pillars, or crowds. Current approaches either passively suppress occluded regions or employ image inpainting techniques that fail to account for temporal coherence and identity consistency. We introduce RestoreGait, an end-to-end framework designed to actively recover occluded gait cues through a lightweight pseudo-3D spatiotemporal decoupled inpainting module. This module decouples spatial contour restoration from temporal motion aggregation, thereby effectively utilizing visible information across multiple frames. Furthermore, an uncertainty-aware soft-gating mechanism is employed to suppress inpainting artifacts of low confidence, whereas a semantic identity consistency loss ensures that the restored sequences maintain discriminative identity features within the deep embedding space, rather than merely achieving visual realism. Extensive experiments on the SUSTech1K, OccGait, Gait3D, and GREW datasets demonstrate that the proposed method yields consistent improvements over strong baselines with negligible computational overhead, demonstrating strong and consistent performance on occluded gait benchmarks.

Siwei Wei · 0 citations