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arxiv: 2605.04569 · v2 · pith:FU7XPACKnew · submitted 2026-05-06 · 💻 cs.CV

LIVEditor-14B: Lightning Unified Video Editing via In-Context Sparse Attention

Shitong Shao , Zikai Zhou , Haopeng Li , Yingwei Song , Wenliang Zhong , Lichen Bai , Zeke Xie This is my paper

Pith reviewed 2026-05-08 16:32 UTC · model grok-4.3

classification 💻 cs.CV
keywords video editingin-context learningsparse attentionquery sharpnessTaylor approximationattention latencyLIVEditor
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The pith

In-context Sparse Attention prunes low-saliency context tokens and routes queries by sharpness to cut attention latency by 60 percent while preserving editing quality.

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

Video editing models that rely on in-context learning face quadratic attention costs that make them slow on longer sequences. The paper introduces In-context Sparse Attention (ISA) which first drops redundant context tokens and then splits queries into groups, sending only the sharpest ones to full attention and the rest to a cheap Taylor approximation. This rests on two observations: context tokens contribute less than source tokens, and query sharpness predicts how much error the approximation will cause. The resulting LIVEditor model, trained on a new 1.7 million example dataset, runs the attention module roughly 60 percent faster than standard transformers and exceeds prior methods on three video-editing benchmarks. A reader would care because the approach removes the main speed barrier for context-aware video editing on ordinary hardware.

Core claim

Context tokens show markedly lower saliency than source tokens, and query sharpness correlates directly with approximation error. ISA therefore prunes redundant context via a lightweight pre-selection step, then applies a dynamic grouping mechanism that assigns high-error queries to full attention and low-error queries to 0-th order Taylor sparse attention. The combined design yields near-lossless sparse attention for in-context video editing.

What carries the argument

In-context Sparse Attention (ISA), which combines saliency-based pre-selection of context tokens with dynamic query grouping that routes queries according to sharpness to either full attention or 0-th order Taylor sparse attention.

If this is right

  • Attention-module latency falls by approximately 60 percent in ICL video editing pipelines.
  • Editing quality exceeds prior state-of-the-art results on EditVerseBench, IVE-Bench, and VIE-Bench.
  • The method avoids the need for task-specific retuning to maintain visual fidelity.
  • A curated 1.7 million high-quality video-editing dataset supports training of the LIVEditor model.
  • Larger context windows become practical without proportional growth in compute.

Where Pith is reading between the lines

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

  • The sharpness-based routing rule could be tested on other ICL tasks such as image or audio editing to check whether similar speed-ups appear.
  • If the saliency gap between context and source tokens holds in other domains, the same pruning step might accelerate multimodal transformer inference more broadly.
  • Practitioners could measure whether the latency reduction scales to longer video sequences without quality degradation.
  • The approach opens a route to real-time context-aware editing tools if the 60 percent saving holds on consumer GPUs.

Load-bearing premise

That the observed link between query sharpness and approximation error, together with the pre-selection and grouping steps, produces near-lossless results on real editing tasks without visual artifacts or per-video retuning.

What would settle it

Side-by-side comparison of full-attention and ISA outputs on a diverse held-out collection of editing prompts and source videos, checking whether human raters or automatic metrics register a measurable quality drop for the sparse version.

Figures

Figures reproduced from arXiv: 2605.04569 by Haopeng Li, Lichen Bai, Shitong Shao, Wenliang Zhong, Yingwei Song, Zeke Xie, Zikai Zhou.

Figure 1
Figure 1. Figure 1: Visualization of LIVEditor (ISA). The superior video editing performance of LIVEditor (ISA) stems from a unified framework that leverages in-context sparse attention. More results can be found in Appendix J. Abstract Video editing has evolved toward In-Context Learning (ICL) paradigms, yet the resulting quadratic attention costs create a critical com￾putational bottleneck. In this work, we propose In-conte… view at source ↗
Figure 2
Figure 2. Figure 2: The speedup of ISA relative to SDPA and FA2 becomes increasingly pronounced as sequence length grows. Within the ISA framework, the computational cost is dominated by the sparse kernel (0-order Taylor attention) and the flat kernel (full-attn), while the overhead of remaining operations is negligible. advancing from domain-specific methods (Ju et al., 2023; Zhang et al., 2023) to unified frameworks (Liang … view at source ↗
Figure 3
Figure 3. Figure 3: The workflow of In-Context Sparse Attention (ISA). ISA optimizes efficiency by enforcing sparsity across both Query and Key/Value dimensions. The process begins by identifying and retaining only the most salient Key and Value pairs from the context tokens. Subsequently, Queries are partitioned based on a computed sharpness metric. Queries exhibiting high sharpness undergo full attention computation, while … view at source ↗
Figure 4
Figure 4. Figure 4: In ICL, the attention matrix exhibits distinct distribu￾tional characteristics, manifesting as four discernible regions. This structural pattern suggests that attention mechanisms should be specifically tailored for ICL scenarios. putation of the attention scores QiK⊤ j and the subsequent aggregation (PQK) ijVj are bypassed. Pooling Attention. Efficiently determining the binary val￾ues of Mij necessitates … view at source ↗
Figure 5
Figure 5. Figure 5: In ICL, attention scores between source Queries and source Keys are typically significantly higher than those between source Queries and context Keys. This disparity becomes increas￾ingly pronounced in deeper layers. this sequence derives from the spatial-temporal tile ordering used in video encoders, the coarse representations preserve local structure while still being hardware-friendly. Stan￾dard attenti… view at source ↗
Figure 7
Figure 7. Figure 7: ISA is a trainable sparse attention mechanism. After post-training, the discrepancy between the output of ISA and that of full attention is significantly reduced across nearly all blocks. 1.0 0.8 0.6 0.4 0.2 0.0 Flat Ratio 1 2 3 4 5 Speedup 1.0 0.8 0.6 0.4 0.2 0.0 No Sparsity Ratio 1.00 1.25 1.50 1.75 2.00 2.25 2.50 2.75 Speedup 16K 32K 64K 128K view at source ↗
Figure 8
Figure 8. Figure 8: Reducing the Flat Ratio αf and No Sparsity Ratio αns leads to an exponential increase in the speedup of ISA relative to SDPA. Moreover, this speedup becomes increasingly pronounced as sequence length grows. Taylor sparse attention is upper-bounded by the product of ||Q(K − Kc ) ⊤||2 ∞ and Mi = [Var(softmax(Qc i (Kc ) ⊤))]. Here, the former term characterizes the mean intra-block variance, while the latter … view at source ↗
Figure 9
Figure 9. Figure 9: EditVerseBench Evaluation Results. The sparsity of ISA is governed by three hyperparameters: Flat Ratio, No Sparsity Ratio, and Select Ratio. Lower values for these parameters induce greater sparsity. Our ablation studies indicate that ISA is particularly sensitive to the Flat Ratio, with performance degrading significantly as this value decreases. In contrast, the model exhibits robustness to variations i… view at source ↗
Figure 10
Figure 10. Figure 10: ISA Performance Visualization. Our proposed ISA not only surpasses VSA, SWA, Sparge Attn, and Radial Attn in inference speed but also outperforms all other sparse attention mechanisms in terms of model performance view at source ↗
Figure 11
Figure 11. Figure 11: The automated synthesis pipeline for video-to-video editing. Our framework consists of 4 integrated stages: (1) Instruction Preparation, where a VLM samples tasks from the Edit Task Pool to generate precise target image instructions based on raw video frames; (2) Target Frame Generation, utilizing the Gemini 2.5 Image Preview to synthesize an anchor frame followed by a VLM-based filtering loop; (3) Target… view at source ↗
Figure 12
Figure 12. Figure 12: Distribution of Editing Tasks in the Constructed Dataset. The dataset comprises diverse editing scenarios, categorized into seven primary tasks. Global editing (e.g., Style Transfer) constitutes the largest portion to ensure stylistic diversity, while fine-grained semantic edits (e.g., Object Swap, Addition, Human Edit) are heavily represented to enhance the model’s instruction-following precision on loca… view at source ↗
Figure 13
Figure 13. Figure 13: One of the system prompt we use in Target Frame Generation phase view at source ↗
Figure 14
Figure 14. Figure 14: The system prompt we use in Target Video Generation phase view at source ↗
Figure 15
Figure 15. Figure 15: The data scheduling strategy for LIVEditor proceeds in two stages. In the first stage, we train on a mixture of high-quality and lower-quality data. In the second stage, we curate a dataset of 0.06M samples generated by Minimax Remover, which is then combined with our proprietary data and three open-source datasets. After extensive filtering, we obtain a final set of 0.089M high-quality samples for fine-t… view at source ↗
Figure 16
Figure 16. Figure 16: Visualization results demonstrate that the Taylor approximation error Ei exhibits negligible correlation with the block variance term ||Q(K − Kc ) ⊤||2∞. (Note that the magnitudes are inflated due to the absence of regularization; view at source ↗
Figure 17
Figure 17. Figure 17: Efficiency Comparison on Hopper GPU: TileLang vs. Triton Implementations of Block-Wise Zeroth-Order Taylor Sparse Attention. 25 view at source ↗
Figure 18
Figure 18. Figure 18: Visualization of LIVEditor (ISA). The method demonstrates robust performance across a diverse set of editing tasks, including object addition, removal, and swapping, as well as hybrid editing, style transfer, and background replacement. 26 view at source ↗
Figure 19
Figure 19. Figure 19: Visualization of LIVEditor (ISA). The method demonstrates robust performance across a diverse set of editing tasks, including object addition, removal, and swapping, as well as hybrid editing, style transfer, and background replacement. 27 view at source ↗
read the original abstract

Video editing has evolved toward In-Context Learning (ICL) paradigms, yet the resulting quadratic attention costs create a critical computational bottleneck. In this work, we propose In-context Sparse Attention (ISA), the first near-lossless empirical sparse framework tailored for ICL video editing. Our design is grounded in two key insights: first, context tokens exhibit significantly lower saliency than source tokens; second, we theoretically prove and empirically validate that Query sharpness correlates with approximation error. Motivated by these findings, ISA implements an efficient pre-selection strategy to prune redundant context, followed by a dynamic query grouping mechanism that routes high-error queries to full attention and low-error ones to a computationally efficient 0-th order Taylor sparse attention. Furthermore, we build \textbf{\texttt{LIVEditor-14B}} , a novel lightning video editing model via ISA and a proposed video-editing data pipeline that curated a 1.7M high-quality dataset. Extensive experiments demonstrate that LIVEditor-14B achieves a $\sim$60% reduction in attention-module latency while surpassing state-of-the-art methods across EditVerseBench, IVE-Bench, and VIE-Bench, delivering near-lossless acceleration without compromising visual fidelity.

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

3 major / 2 minor

Summary. The manuscript proposes In-context Sparse Attention (ISA) as a sparse attention framework for in-context learning (ICL) video editing. It identifies lower saliency in context tokens versus source tokens, claims a theoretical proof that query sharpness correlates with approximation error, and implements pre-selection pruning of redundant context followed by dynamic grouping that routes high-error queries to full attention and low-error queries to 0-th order Taylor sparse attention. The method is integrated into a new model LIVEditor trained on a curated 1.7M high-quality video editing dataset, with experiments claiming ~60% reduction in attention-module latency while outperforming prior methods on EditVerseBench, IVE-Bench, and VIE-Bench under a near-lossless quality regime.

Significance. If the claimed correlation between query sharpness and approximation error can be shown to provide tight bounds that keep the 0-th order Taylor approximation near-lossless, and if the empirical routing thresholds generalize without per-video retuning or temporal artifacts, the work would offer a practical acceleration technique for quadratic-cost ICL video editing. The scale of the curated dataset and the multi-benchmark evaluation would also constitute a useful resource for the community.

major comments (3)
  1. [Abstract] Abstract: The manuscript asserts both a 'theoretical proof' and 'empirical validation' that query sharpness correlates with approximation error and thereby justifies routing low-error queries to 0-th order Taylor sparse attention. No equations, proof sketch, error-bound derivation, or quantitative correlation analysis appear in the provided text, yet this correlation is load-bearing for the central near-lossless claim.
  2. [Method] Method description: The pre-selection and dynamic grouping steps rely on two free parameters (context pruning threshold, query error threshold for grouping). These are described as empirically chosen, but no ablation or sensitivity analysis demonstrates that the resulting error remains bounded independently of the target benchmarks (EditVerseBench, IVE-Bench, VIE-Bench).
  3. [Experiments] Experiments: The reported ~60% attention latency reduction and 'near-lossless' quality are presented without error bars, per-query error histograms, or failure-case analysis for temporally inconsistent artifacts on low-sharpness queries. This leaves the claim that the routing decision yields near-lossless output on real editing tasks unverified.
minor comments (2)
  1. [Title] The title uses 'Lightning' as an adjective; clarify whether this is a proper name for the model or merely descriptive.
  2. [Method] Notation for the 0-th order Taylor approximation and the sharpness metric should be introduced with explicit definitions before the dynamic grouping description.

Simulated Author's Rebuttal

3 responses · 0 unresolved

We thank the referee for the constructive and detailed feedback. We address each major comment below and commit to revisions that strengthen the theoretical grounding, parameter analysis, and experimental validation without altering the core claims.

read point-by-point responses

  1. Referee: [Abstract] Abstract: The manuscript asserts both a 'theoretical proof' and 'empirical validation' that query sharpness correlates with approximation error and thereby justifies routing low-error queries to 0-th order Taylor sparse attention. No equations, proof sketch, error-bound derivation, or quantitative correlation analysis appear in the provided text, yet this correlation is load-bearing for the central near-lossless claim.

    Authors: We acknowledge the omission of the detailed derivation from the main text for space reasons. A full proof sketch deriving the correlation between query sharpness and the 0-th order Taylor approximation error (including the error-bound expression) together with quantitative correlation plots will be added to the revised main paper. This directly supports the routing decision and the near-lossless regime. revision: yes

  2. Referee: [Method] Method description: The pre-selection and dynamic grouping steps rely on two free parameters (context pruning threshold, query error threshold for grouping). These are described as empirically chosen, but no ablation or sensitivity analysis demonstrates that the resulting error remains bounded independently of the target benchmarks (EditVerseBench, IVE-Bench, VIE-Bench).

    Authors: We agree that explicit sensitivity analysis is required. The revised manuscript will include a new ablation subsection that sweeps both thresholds across a range of values and reports the resulting attention error and visual metrics on all three benchmarks. The results confirm that a single fixed pair of thresholds keeps error bounded without per-video retuning or introduction of temporal artifacts. revision: yes

  3. Referee: [Experiments] Experiments: The reported ~60% attention latency reduction and 'near-lossless' quality are presented without error bars, per-query error histograms, or failure-case analysis for temporally inconsistent artifacts on low-sharpness queries. This leaves the claim that the routing decision yields near-lossless output on real editing tasks unverified.

    Authors: We will augment the experimental section with (i) error bars over multiple random seeds for both latency and quality metrics, (ii) per-query error histograms that explicitly visualize the sharpness-error correlation, and (iii) a dedicated failure-case study examining temporal consistency on low-sharpness queries. These additions will provide quantitative verification of the near-lossless claim. revision: yes

Circularity Check

0 steps flagged

No significant circularity; derivation relies on independent theoretical proof and external benchmarks

full rationale

The paper's core derivation begins with two stated insights (lower context saliency and the correlation between query sharpness and approximation error), followed by a claimed theoretical proof of the correlation, an empirical pre-selection strategy, and a dynamic routing rule that assigns queries to either full attention or 0-th order Taylor approximation. These steps are presented as motivated by the proof rather than defined in terms of the final performance metric. The LIVEditor model and 1.7M dataset are constructed via a separate data pipeline. Final claims of ~60% latency reduction and superiority on EditVerseBench, IVE-Bench, and VIE-Bench are reported as post-hoc validation on held-out benchmarks, not as inputs that define the routing thresholds or the proof. No equations, self-citations, or fitted parameters are shown to reduce the claimed result to the inputs by construction.

Axiom & Free-Parameter Ledger

2 free parameters · 2 axioms · 2 invented entities

The design rests on two domain assumptions about token saliency and query sharpness that are not derived from first principles but asserted as insights; the method introduces new entities (ISA, LIVEditor) and likely several tunable thresholds whose values are not reported.

free parameters (2)
  • context pruning threshold
    Controls how many low-saliency context tokens are dropped; value must be chosen or fitted to maintain quality.
  • query error threshold for grouping
    Decides which queries receive full attention versus Taylor approximation; appears tuned empirically.
axioms (2)
  • domain assumption Context tokens exhibit significantly lower saliency than source tokens.
    First key insight used to justify pruning.
  • domain assumption Query sharpness correlates with approximation error.
    Second insight, claimed to be theoretically proved and empirically validated.
invented entities (2)
  • In-context Sparse Attention (ISA) no independent evidence
    purpose: Near-lossless sparse attention framework for ICL video editing.
    Core new method proposed in the paper.
  • LIVEditor no independent evidence
    purpose: Lightning video editing model built on ISA.
    New model name and implementation.

pith-pipeline@v0.9.0 · 5520 in / 1545 out tokens · 45717 ms · 2026-05-08T16:32:41.371872+00:00 · methodology

discussion (0)

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