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arxiv: 2604.14648 · v1 · submitted 2026-04-16 · 💻 cs.CV · cs.AI· cs.LG

Recognition: unknown

Seen-to-Scene: Keep the Seen, Generate the Unseen for Video Outpainting

Authors on Pith no claims yet

Pith reviewed 2026-05-10 12:08 UTC · model grok-4.3

classification 💻 cs.CV cs.AIcs.LG
keywords video outpaintingtemporal coherenceflow completion networklatent propagationvideo generationdiffusion modelsmotion fieldsscene expansion
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The pith

Unifying flow propagation of seen content with latent generation for unseen areas improves temporal consistency in video outpainting

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

The paper proposes Seen-to-Scene as a framework to expand video content beyond original frame boundaries while preserving spatial fidelity and temporal coherence. It unifies propagation of existing content through an end-to-end fine-tuned flow completion network adapted from inpainting with reference-guided latent propagation for reliable spreading across frames. This hybrid approach targets inconsistencies that arise in purely generative methods like diffusion models, particularly in dynamic scenes or large expansions, and claims efficient inference without input-specific adaptation. A sympathetic reader would care because consistent video expansion supports applications in editing and content creation where motion artifacts currently limit usability.

Core claim

Seen-to-Scene unifies propagation-based and generation-based paradigms for video outpainting by leveraging a flow completion network pre-trained for video inpainting, which is fine-tuned in an end-to-end manner to bridge the domain gap and reconstruct coherent motion fields, together with reference-guided latent propagation that effectively propagates source content across frames, achieving superior temporal coherence and visual realism with efficient inference that surpasses prior state-of-the-art methods even those requiring input-specific adaptation.

What carries the argument

Flow completion network adapted from video inpainting via end-to-end fine-tuning, paired with reference-guided latent propagation for content spreading

If this is right

  • Expanded videos maintain spatial fidelity and inter-frame motion consistency without per-input retraining.
  • The method handles dynamic scenes and large expansion scenarios more reliably than generation-only approaches.
  • Inference remains efficient while delivering higher visual realism than prior state-of-the-art techniques.
  • Hybrid propagation reduces intra-frame and inter-frame inconsistencies that limit current video outpainting tools.

Where Pith is reading between the lines

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

  • The same adaptation strategy for flow networks might transfer to related video tasks such as interpolation or stabilization where motion coherence is central.
  • Longer sequences could benefit disproportionately because propagation limits error buildup that pure generation accumulates over many frames.
  • Real-time video editing pipelines might adopt this for speed gains if the fine-tuning proves stable across varied input resolutions.

Load-bearing premise

A flow completion network pre-trained for video inpainting can be fine-tuned end-to-end to accurately reconstruct coherent motion fields when applied to outpainting instead of inpainting, especially across dynamic scenes and large boundary expansions.

What would settle it

Experiments on videos with rapid object motion or large outpainting ratios that show increased flickering, motion discontinuities, or visual artifacts in the generated regions compared to pure diffusion baselines would indicate the fine-tuning fails to bridge the domain gap.

Figures

Figures reproduced from arXiv: 2604.14648 by Inseok Jeon, Minhyeok Lee, Minseok Kang, Sangyoun Lee, Seunghoon Lee, Suhwan Cho.

Figure 1
Figure 1. Figure 1: Seen-to-Scene is a novel framework that unifies propagation-based and generation-based paradigms for video outpainting. It maintains strong spatio-temporal consistency across frames even under challenging conditions such as camera motion, dynamic objects and complex motion patterns. The official implementation is released at https://github.com/InSeokJeon/Seen_to_Scene. Abstract Video outpainting aims to ex… view at source ↗
Figure 2
Figure 2. Figure 2: Computational cost comparison with a SOTA [PITH_FULL_IMAGE:figures/full_fig_p002_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: Key limitations of existing video outpainting approaches. (a) Flow completion domain gap: Flow completion networks trained for video inpainting struggle to generalize to video outpainting due to the substantially larger missing regions involved. Consequently, the predicted flow often suffers from bleeding around dynamic objects and fails to provide reliable motion estimates for regions far from the origina… view at source ↗
Figure 4
Figure 4. Figure 4: Overview of the proposed Seen-to-Scene framework. Seen-to-Scene unifies propagation and generation for coherent video outpainting. Given an input video, reference frames are selected and optical flow is estimated using RAFT [17], followed by flow comple￾tion with FCNet [28]. The input frames are encoded into latent representations via a pre-trained VAE encoder. Using the completed flow, we perform referenc… view at source ↗
Figure 5
Figure 5. Figure 5: Comparison of flow completion results between an in [PITH_FULL_IMAGE:figures/full_fig_p007_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: Visualization of warping results using an inpainting pre [PITH_FULL_IMAGE:figures/full_fig_p007_6.png] view at source ↗
Figure 7
Figure 7. Figure 7: Qualitative comparison between Seen-to-Scene and State-of-the-art methods. [PITH_FULL_IMAGE:figures/full_fig_p008_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: Effect of the temporal window size m on FVD. m = 4 in our method, which effectively balances temporal consistency and computational efficiency. 6. Conclusion and Future Work In this work, we present Seen-to-Scene, a novel end-to-end framework that unifies propagation-based and diffusion￾based paradigms for video outpainting. We further in￾troduce an efficient and effective reference-guided latent propagati… view at source ↗
Figure 9
Figure 9. Figure 9: Two settings of video inpainting: (a) Object Removal [PITH_FULL_IMAGE:figures/full_fig_p009_9.png] view at source ↗
Figure 12
Figure 12. Figure 12: Comparison of fixed-stride and similarity-based reference selection. While the fixed-stride method selects frame (d) with [PITH_FULL_IMAGE:figures/full_fig_p010_12.png] view at source ↗
Figure 13
Figure 13. Figure 13: Visualization of flow completion results. Our outpainting fine-tuned model produces geometrically stable and semantically separated motion fields compared to inpainting-pretrained flow completion. coherent and extends seamlessly into the expanded regions. The fine-tuned model learns to infer long-range and cross￾boundary motion more robustly, resulting in stable propaga￾tion even for highly dynamic scenes… view at source ↗
Figure 14
Figure 14. Figure 14: Visualization of pixel-level warping using different flow completion networks. Our outpainting fine-tuned model achieves stable propagation, while the inpainting pre-trained model fails to propagate content effectively to outpainting regions. C.2. Latent Refinement To refine warped multi-frame latents for video outpaint￾ing, we introduce a dual-branch refinement module that op￾erates directly on the warpe… view at source ↗
Figure 15
Figure 15. Figure 15: Visualization of propagation strategies. (a) Con￾ventional sequential propagation accumulates flow across all inter￾mediate frames, while (b) our reference-guided latent propagation performs efficient warping using only selected references in the latent space. FW Propagated Latent Original Latent Original VO Mask FW Propagated Region Mask 𝐶 CONV Offset Mask DCN 𝐶 CONV Offset Mask DCN CONV CONV 𝑆 𝑆 1 x 1 C… view at source ↗
Figure 16
Figure 16. Figure 16: Architecture of the latent refinement module. It refines propagated latent features through spatial alignment and residual correction, enhancing temporal consistency and visual co￾herence in the outpainted video. backward-propagated latents obtained from bi-directional warping, and then concatenate the two refined latents and pass them through a final convolutional layer to produce a unified, refined bi-d… view at source ↗
Figure 17
Figure 17. Figure 17: Qualitative results of our method across diverse scenarios and environments. The examples demonstrate the robustness and generalization capability of our model in handling various motion patterns, scene complexities, and outpainting configurations [PITH_FULL_IMAGE:figures/full_fig_p016_17.png] view at source ↗
Figure 18
Figure 18. Figure 18: Qualitative results across different spatial resolutions and aspect ratios. Our method maintains consistent visual quality and structure from 256 × 256 to extended formats such as 256 × 512 and 256 × 768 [PITH_FULL_IMAGE:figures/full_fig_p017_18.png] view at source ↗
read the original abstract

Video outpainting aims to expand the visible content of a video beyond the original frame boundaries while preserving spatial fidelity and temporal coherence across frames. Existing methods primarily rely on large-scale generative models, such as diffusion models. However, generationbased approaches suffer from implicit temporal modeling and limited spatial context. These limitations lead to intraframe and inter-frame inconsistencies, which become particularly pronounced in dynamic scenes and large outpainting scenarios. To overcome these challenges, we propose Seen-to-Scene, a novel framework that unifies propagationbased and generation-based paradigms for video outpainting. Specifically, Seen-to-Scene leverages flow-based propagation with a flow completion network pre-trained for video inpainting, which is fine-tuned in an end-to-end manner to bridge the domain gap and reconstruct coherent motion fields. To further improve the efficiency and reliability of propagation, we introduce a reference-guided latent propagation that effectively propagates source content across frames. Extensive experiments demonstrate that our method achieves superior temporal coherence and visual realism with efficient inference, surpassing even prior state-of-the-art methods that require input-specific adaptation.

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 / 2 minor

Summary. The paper proposes Seen-to-Scene, a video outpainting framework that unifies propagation-based and generation-based approaches by leveraging a flow completion network pre-trained on video inpainting, fine-tuned end-to-end to reconstruct coherent motion fields, combined with reference-guided latent propagation to expand frames while preserving spatial fidelity and temporal coherence, claiming superior results over diffusion models especially in dynamic scenes and large expansions.

Significance. If the experimental validation holds, the work offers a potentially more efficient alternative to large generative models for video outpainting by adapting propagation techniques, which could improve temporal consistency without requiring per-input adaptation.

major comments (2)
  1. [Abstract] Abstract: the central claim that end-to-end fine-tuning of an inpainting-pretrained flow completion network successfully bridges the domain gap for outpainting extrapolation is asserted without any quantitative results, ablation details, or explicit mechanism (e.g., specialized loss terms or architectural modifications) to address the fundamental asymmetry between inpainting (surrounded context) and outpainting (one-sided missing context).
  2. [Method] Method description (flow-based propagation): the assumption that a network trained for motion completion in inpainting can extrapolate coherent motions in dynamic scenes and large expansion ratios lacks supporting analysis or targeted experiments demonstrating robustness to the lack of outer reference pixels, which is load-bearing for the superiority claim over diffusion baselines.
minor comments (2)
  1. [Abstract] Abstract: the phrase 'unifies propagation-based and generation-based paradigms' is used but the precise integration point between the flow propagation and any generative component is not clarified in the high-level description.
  2. [Discussion] The paper would benefit from a dedicated limitations or failure-case discussion section, particularly for scenarios where motion extrapolation may break down.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the constructive feedback. We address each major comment point by point below with clarifications from the manuscript and indicate planned revisions.

read point-by-point responses
  1. Referee: [Abstract] Abstract: the central claim that end-to-end fine-tuning of an inpainting-pretrained flow completion network successfully bridges the domain gap for outpainting extrapolation is asserted without any quantitative results, ablation details, or explicit mechanism (e.g., specialized loss terms or architectural modifications) to address the fundamental asymmetry between inpainting (surrounded context) and outpainting (one-sided missing context).

    Authors: The abstract summarizes the core contribution at a high level, as is standard. Quantitative results validating the fine-tuned network's performance (including temporal coherence metrics outperforming diffusion baselines in dynamic scenes) appear in Section 4, with ablation studies on the end-to-end fine-tuning in Section 4.2. The mechanism for handling asymmetry relies on the reference-guided latent propagation combined with flow consistency losses during fine-tuning, which adapt the pre-trained inpainting model to extrapolate from one-sided seen context; this is detailed in Section 3.2. We will revise the abstract to include a concise reference to these experimental validations and the adaptation process. revision: partial

  2. Referee: [Method] Method description (flow-based propagation): the assumption that a network trained for motion completion in inpainting can extrapolate coherent motions in dynamic scenes and large expansion ratios lacks supporting analysis or targeted experiments demonstrating robustness to the lack of outer reference pixels, which is load-bearing for the superiority claim over diffusion baselines.

    Authors: The manuscript supports this through extensive experiments in Section 4.1 and 4.3, where the method shows superior results over diffusion models specifically in dynamic scenes and large expansions, measured by metrics such as warping error and perceptual quality. The reference-guided latent propagation (Section 3.3) is designed to compensate for missing outer pixels by propagating from seen content across frames using the adapted flow fields. To strengthen the response to this valid point, we will add a targeted analysis subsection in the revision discussing robustness across expansion ratios and scene dynamics, including qualitative examples of motion extrapolation without outer references. revision: yes

Circularity Check

0 steps flagged

No circularity: method relies on external pre-training and standard fine-tuning without self-referential reductions.

full rationale

The abstract and described framework use a pre-trained flow completion network (from inpainting) that is then fine-tuned end-to-end. No equations, derivations, or load-bearing claims are presented that reduce by construction to parameters or definitions internal to the paper itself. The approach cites external pre-trained components and standard techniques; superiority claims rest on empirical results rather than any self-definitional or fitted-input-as-prediction structure. This matches the default expectation of a non-circular paper.

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 method description mentions a pre-trained network and fine-tuning but does not enumerate any fitted constants or new postulated components.

pith-pipeline@v0.9.0 · 5513 in / 1125 out tokens · 40343 ms · 2026-05-10T12:08:27.154700+00:00 · methodology

discussion (0)

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Reference graph

Works this paper leans on

28 extracted references · 8 canonical work pages · 4 internal anchors

  1. [1]

    Stable Video Diffusion: Scaling Latent Video Diffusion Models to Large Datasets

    Andreas Blattmann, Tim Dockhorn, Sumith Kulal, Daniel Mendelevitch, Maciej Kilian, Dominik Lorenz, Yam Levi, Zion English, Vikram V oleti, Adam Letts, et al. Stable video diffusion: Scaling latent video diffusion models to large datasets.arXiv preprint arXiv:2311.15127, 2023. 2, 6

  2. [2]

    arXiv preprint arXiv:2409.01055 (2024)

    Qihua Chen, Yue Ma, Hongfa Wang, Junkun Yuan, Wenzhe Zhao, Qi Tian, Hongmei Wang, Shaobo Min, Qifeng Chen, and Wei Liu. Follow-your-canvas: Higher-resolution video outpainting with extensive content generation.arXiv preprint arXiv:2409.01055, 2024. 2, 3, 6, 7, 15

  3. [3]

    Panda-70m: Captioning 70m videos with multiple cross-modality teachers

    Tsai-Shien Chen, Aliaksandr Siarohin, Willi Menapace, Ekaterina Deyneka, Hsiang-wei Chao, Byung Eun Jeon, Yuwei Fang, Hsin-Ying Lee, Jian Ren, Ming-Hsuan Yang, et al. Panda-70m: Captioning 70m videos with multiple cross-modality teachers. InProceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, pages 13320–13331, 2024. 6

  4. [4]

    Elevating flow-guided video inpainting with ref- erence generation

    Suhwan Cho, Seoung Wug Oh, Sangyoun Lee, and Joon- Young Lee. Elevating flow-guided video inpainting with ref- erence generation. InProceedings of the AAAI Conference on Artificial Intelligence, pages 2527–2535, 2025. 1, 2, 3, 5, 9

  5. [5]

    Complete and temporally consistent video out- painting

    Lo ¨ıc Dehan, Wiebe Van Ranst, Patrick Vandewalle, and Toon Goedem´e. Complete and temporally consistent video out- painting. InProceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, pages 687–695,

  6. [6]

    Hierar- chical masked 3d diffusion model for video outpainting

    Fanda Fan, Chaoxu Guo, Litong Gong, Biao Wang, Tiezheng Ge, Yuning Jiang, Chunjie Luo, and Jianfeng Zhan. Hierar- chical masked 3d diffusion model for video outpainting. In Proceedings of the 31st ACM International Conference on Multimedia, pages 7890–7900, 2023. 2, 3, 6, 7, 15

  7. [7]

    Denoising dif- fusion probabilistic models.Advances in neural information processing systems, 33:6840–6851, 2020

    Jonathan Ho, Ajay Jain, and Pieter Abbeel. Denoising dif- fusion probabilistic models.Advances in neural information processing systems, 33:6840–6851, 2020. 2

  8. [8]

    Adam: A Method for Stochastic Optimization

    Diederik P Kingma. Adam: A method for stochastic opti- mization.arXiv preprint arXiv:1412.6980, 2014. 6

  9. [9]

    Auto-Encoding Variational Bayes

    Diederik P Kingma and Max Welling. Auto-encoding varia- tional bayes.arXiv preprint arXiv:1312.6114, 2013. 4

  10. [10]

    Video diffusion models are strong video inpainter

    Minhyeok Lee, Suhwan Cho, Chajin Shin, Jungho Lee, Sunghun Yang, and Sangyoun Lee. Video diffusion models are strong video inpainter. InProceedings of the AAAI Con- ference on Artificial Intelligence, pages 4526–4533, 2025. 1

  11. [11]

    Dynamic shadow un- veils invisible semantics for video outpainting

    Ruilin Li, Hang Yu, and Jiayan Qiu. Dynamic shadow un- veils invisible semantics for video outpainting. InThe Thirty- ninth Annual Conference on Neural Information Processing Systems. 2, 3, 7

  12. [12]

    Towards an end-to-end framework for flow-guided video inpainting

    Zhen Li, Cheng-Ze Lu, Jianhua Qin, Chun-Le Guo, and Ming-Ming Cheng. Towards an end-to-end framework for flow-guided video inpainting. InProceedings of the IEEE/CVF conference on computer vision and pattern recognition, pages 17562–17571, 2022. 1, 3

  13. [13]

    M3ddm+: An improved video outpaint- ing by a modified masking strategy.arXiv preprint arXiv:2601.11048, 2026

    Takuya Murakawa, Takumi Fukuzawa, Ning Ding, and Toru Tamaki. M3ddm+: An improved video outpaint- ing by a modified masking strategy.arXiv preprint arXiv:2601.11048, 2026. 2

  14. [14]

    Globalpaint: Spatiotemporal coherent video outpainting with global feature guidance.arXiv preprint arXiv:2601.06413, 2026

    Yueming Pan, Ruoyu Feng, Jianmin Bao, Chong Luo, and Nanning Zheng. Globalpaint: Spatiotemporal coherent video outpainting with global feature guidance.arXiv preprint arXiv:2601.06413, 2026. 2, 7

  15. [15]

    A benchmark dataset and evaluation methodology for video object segmentation

    Federico Perazzi, Jordi Pont-Tuset, Brian McWilliams, Luc Van Gool, Markus Gross, and Alexander Sorkine-Hornung. A benchmark dataset and evaluation methodology for video object segmentation. InProceedings of the IEEE conference on computer vision and pattern recognition, pages 724–732,

  16. [16]

    High-resolution image synthesis with latent diffusion models

    Robin Rombach, Andreas Blattmann, Dominik Lorenz, Patrick Esser, and Bj ¨orn Ommer. High-resolution image synthesis with latent diffusion models. InProceedings of the IEEE/CVF conference on computer vision and pattern recognition, pages 10684–10695, 2022. 4

  17. [17]

    Raft: Recurrent all-pairs field transforms for optical flow

    Zachary Teed and Jia Deng. Raft: Recurrent all-pairs field transforms for optical flow. InEuropean conference on com- puter vision, pages 402–419. Springer, 2020. 4, 5

  18. [18]

    Towards Accurate Generative Models of Video: A New Metric & Challenges

    Thomas Unterthiner, Sjoerd Van Steenkiste, Karol Kurach, Raphael Marinier, Marcin Michalski, and Sylvain Gelly. To- wards accurate generative models of video: A new metric & challenges.arXiv preprint arXiv:1812.01717, 2018. 6

  19. [19]

    Be-your-outpainter: Mastering video outpainting through input-specific adaptation

    Fu-Yun Wang, Xiaoshi Wu, Zhaoyang Huang, Xiaoyu Shi, Dazhong Shen, Guanglu Song, Yu Liu, and Hongsheng Li. Be-your-outpainter: Mastering video outpainting through input-specific adaptation. InEuropean Conference on Com- puter Vision, pages 153–168. Springer, 2024. 2, 3, 6, 7, 15

  20. [20]

    Image quality assessment: from error visibility to structural similarity.IEEE transactions on image processing, 13(4):600–612, 2004

    Zhou Wang, Alan C Bovik, Hamid R Sheikh, and Eero P Si- moncelli. Image quality assessment: from error visibility to structural similarity.IEEE transactions on image processing, 13(4):600–612, 2004. 5, 6

  21. [21]

    Youtube-vos: Sequence-to-sequence video object segmentation

    Ning Xu, Linjie Yang, Yuchen Fan, Jianchao Yang, Dingcheng Yue, Yuchen Liang, Brian Price, Scott Cohen, and Thomas Huang. Youtube-vos: Sequence-to-sequence video object segmentation. InProceedings of the Euro- pean conference on computer vision (ECCV), pages 585– 601, 2018. 6

  22. [22]

    Deep flow-guided video inpainting

    Rui Xu, Xiaoxiao Li, Bolei Zhou, and Chen Change Loy. Deep flow-guided video inpainting. InProceedings of the IEEE/CVF conference on computer vision and pattern recognition, pages 3723–3732, 2019. 3

  23. [23]

    Unboxed: Geometrically and tem- porally consistent video outpainting

    Zhongrui Yu, Martina Megaro-Boldini, Robert W Sumner, and Abdelaziz Djelouah. Unboxed: Geometrically and tem- porally consistent video outpainting. InProceedings of the Computer Vision and Pattern Recognition Conference, pages 7309–7319, 2025. 2, 3, 6, 15

  24. [24]

    Flow-guided transformer for video inpainting

    Kaidong Zhang, Jingjing Fu, and Dong Liu. Flow-guided transformer for video inpainting. InEuropean conference on computer vision, pages 74–90. Springer, 2022. 1

  25. [25]

    Inertia-guided flow completion and style fusion for video inpainting

    Kaidong Zhang, Jingjing Fu, and Dong Liu. Inertia-guided flow completion and style fusion for video inpainting. In Proceedings of the IEEE/CVF conference on computer vi- sion and pattern recognition, pages 5982–5991, 2022. 1

  26. [26]

    The unreasonable effectiveness of deep features as a perceptual metric

    Richard Zhang, Phillip Isola, Alexei A Efros, Eli Shecht- man, and Oliver Wang. The unreasonable effectiveness of deep features as a perceptual metric. InProceedings of the IEEE conference on computer vision and pattern recogni- tion, pages 586–595, 2018. 6

  27. [27]

    Outdreamer: Video out- painting with a diffusion transformer.arXiv preprint arXiv:2506.22298, 2025

    Linhao Zhong, Fan Li, Yi Huang, Jianzhuang Liu, Ren- jing Pei, and Fenglong Song. Outdreamer: Video out- painting with a diffusion transformer.arXiv preprint arXiv:2506.22298, 2025. 2, 7

  28. [28]

    Propainter: Improving propagation and transformer for video inpainting

    Shangchen Zhou, Chongyi Li, Kelvin CK Chan, and Chen Change Loy. Propainter: Improving propagation and transformer for video inpainting. InProceedings of the IEEE/CVF international conference on computer vision, pages 10477–10486, 2023. 1, 3, 4, 5, 9