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arxiv: 2606.03183 · v1 · pith:3VJBIKB7new · submitted 2026-06-02 · 💻 cs.MM · cs.CV· cs.SD· eess.AS

Inference-Time Scaling for Joint Audio-Video Generation

Pith reviewed 2026-06-28 07:47 UTC · model grok-4.3

classification 💻 cs.MM cs.CVcs.SDeess.AS
keywords inference-time scalingjoint audio-video generationmulti-verifier frameworkadaptive reward weightingsemantic alignmentaudio-visual synchronizationtest-time optimization
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The pith

A multi-verifier framework plus adaptive reward weighting enables effective inference-time scaling for joint audio-video generation.

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

The paper investigates how to apply inference-time scaling to the joint generation of audio and video from text prompts. It establishes that single-objective guidance creates uneven trade-offs and allows models to exploit individual verifiers, so multiple verifiers must be combined. The authors then introduce Adaptive Reward Weighting, an online optimization step that learns to balance the different reward signals on the fly. Experiments on VGGSound and JavisBench-mini show gains in semantic alignment, perceptual quality, and audio-visual timing. This matters because it offers a training-free route to higher-quality multimodal outputs.

Core claim

The authors claim that inference-time scaling for joint audio-video generation requires a multi-verifier setup to avoid asymmetric trade-offs and verifier hacking, and that Adaptive Reward Weighting aggregates the resulting signals by treating reward balancing as an online optimization problem with learnable parameters that calibrate variances without prior distributional knowledge.

What carries the argument

Adaptive Reward Weighting (ARW), a test-time algorithm that performs online optimization over learnable parameters to calibrate and combine multiple reward signals during generation.

If this is right

  • The chosen multi-verifier combination produces balanced gains across semantic alignment, perceptual quality, and audio-visual synchronization.
  • Adaptive Reward Weighting aggregates heterogeneous rewards without needing advance knowledge of their distributions.
  • The resulting outputs improve on VGGSound and JavisBench-mini relative to prior joint generation baselines.
  • All improvements occur at inference time without additional model training.

Where Pith is reading between the lines

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

  • The same multi-verifier structure could be tested on other pairs of modalities whose quality metrics conflict during generation.
  • If ARW's learnable parameters converge reliably, the method may reduce the need for hand-tuned reward weights in future multimodal systems.
  • The approach implies that test-time compute can substitute for some of the training compute currently spent on multimodal alignment.

Load-bearing premise

Single-objective guidance necessarily produces asymmetric performance trade-offs and verifier hacking, so multiple verifiers are required.

What would settle it

An experiment that applies single-verifier inference-time scaling to the same base model and benchmarks and measures equal or superior scores across semantic alignment, perceptual quality, and synchronization would falsify the necessity of the multi-verifier approach.

Figures

Figures reproduced from arXiv: 2606.03183 by Inkyu Shin, Jaemin Jung, Joon Son Chung, Kyeongha Rho.

Figure 1
Figure 1. Figure 1: Qualitative results with Inference-Time Scaling. Compared to naive sampling, ITS yields audio–video pairs with superior semantic alignment with the text prompt and cross-modal synchronization. The video samples are available at the following link. Joint audio-video generation aims to simultaneously synthesize auditory and visual streams that are tem￾porally synchronized and semantically aligned. MM-Diffusi… view at source ↗
Figure 2
Figure 2. Figure 2: Comparison of reward guidance types and aggregation methods. The overall performance improvement is calculated by averaging the relative improvements of all evaluation metrics compared to the naive sampling (without ITS). This result is obtained with JavisDiT. where {βt} T t=1 denotes the noise schedule and ϵ represents standard Gaussian noise. Then, a conditional denoising network ϵθ(xt, s, t) is trained … view at source ↗
Figure 3
Figure 3. Figure 3: Overview of Adaptive Reward Weighting. Given audio-video samples generated by the pre￾trained generative model, they are evaluated by multiple verifiers, with their raw rewards stored in a history buffer. Then, the aggregated score is computed via a weighted sum of these rewards using reward-specific learnable calibration parameters, and calibration parameters are updated through test-time optimization. Th… view at source ↗
Figure 4
Figure 4. Figure 4: Inference-time scaling curves across the number of samples. Across both Best-of-N and EvoSearch, the Z-score and ARW aggregation methods exhibit consistent performance improvement as the sample size increases. In both (a) and (b), the left and right panels show VR and JS scores, respectively. This balance is particularly critical for an iterative search algorithm. The performance gap between Best￾of-N and … view at source ↗
Figure 5
Figure 5. Figure 5: Human evaluation results. Impact of Inference-Time Scaling. To evaluate the scalability of the proposed methods, we apply Z￾score normalization and ARW to two ITS strategies while gradually increasing the samples. As illustrated in [PITH_FULL_IMAGE:figures/full_fig_p011_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: Qualitative comparison of generated samples. We compare the outputs of naive sampling, single-verifier (VR-guidance), and our multi-verifier (ARW) given a complex text prompt on JavisDiT. The video samples are available at the following link. samples. These subjective findings further corroborate the objective evaluations reported in [PITH_FULL_IMAGE:figures/full_fig_p012_6.png] view at source ↗
Figure 7
Figure 7. Figure 7: Sensitivity analysis of preference weights. We vary the preference weights in Eq. 3 from 0.3 to 0.7 in increments of 0.1. Increasing the weight for VideoReward-TA improves text consistency, whereas emphasizing JavisScore enhances AV consistency. Notably, the method demonstrates robustness, maintaining stable performance in both modalities without sudden degradation across the tested range. D.3 Hyperparamet… view at source ↗
Figure 8
Figure 8. Figure 8: Convergence behavior of ARW under different optimizers. We plot the calibration loss (top) and the learned scale parameters (bottom) for Adam, SGD, and RMSprop. All optimizers converge to similar final solutions, although their early optimization dynamics differ. Overall, the results indicate that ARW is stable and largely insensitive to optimizer choice. D.5 Generalization to a Stronger AV-Generation Mode… view at source ↗
Figure 9
Figure 9. Figure 9: Qualitative comparison of generated samples. We compare the outputs of naive sampling, single-verifier (VR-guidance), and our multi-verifier (ARW) given a complex text prompt on JavisDiT. Naive sampling fails to respect the count constraint, generating three pigeons. Single-verifier guidance misses the fine-grained visual detail, failing to render the mesh fence. Multi-verifier successfully satisfies all c… view at source ↗
Figure 10
Figure 10. Figure 10: Qualitative comparison of generated samples. We compare the outputs of naive sampling, single-verifier (VR-guidance), and our multi-verifier (ARW) given a complex text prompt on JavisDiT. Naive sampling fails to generate the specific audio event. Single-verifier misinterprets the audio description as a visual cue, hallucinating a bird’s wing in the video frame. Multi-verifier correctly assigns the semanti… view at source ↗
Figure 11
Figure 11. Figure 11: Qualitative comparison of generated samples. We compare the outputs of naive sampling and our multi-verifier (ARW) approach using text prompts from MMDisCo. The results demonstrate the correction of semantic and physical failures. In the top example, naive sampling generates a bird with severe anatomical distortion (head twisted backwards), whereas our method ensures physical correctness and generates syn… view at source ↗
Figure 12
Figure 12. Figure 12: Qualitative results on prompt variability. We compare the videos conditioned on the original JavisBench-mini prompt and its three transformed variants: conversational style, fragment-style, and grammar-typo prompts. Without ITS, naive sampling often fails to preserve key prompt details, such as the visible pouring stream and the surface dynamics of the oil. In contrast, ITS generates videos that more cons… view at source ↗
Figure 13
Figure 13. Figure 13: Qualitative results on prompt variability. We compare the outputs conditioned on the original JavisBench-mini prompt and its three transformed variants: conversational style, fragment-style, and grammar-typo prompts. Without ITS, naive sampling often fails to preserve key prompt semantics under prompt variation: it loses the intended interaction between the two birds, hallucinates an additional orange bir… view at source ↗
Figure 14
Figure 14. Figure 14: Qualitative comparison on LTX-2. We compare naive sampling and multi-verifier ITS with ARW on a stronger open-source joint audio-video generation model. Top: ITS better satisfies the fine￾grained bird attributes and count. Bottom: ITS better follows the intended helicopter motion direction. These examples suggest that ARW improves prompt-faithful audiovisual generation on LTX-2 as well. The video samples … view at source ↗
Figure 15
Figure 15. Figure 15: Qualitative comparison on LTX-2. We compare naive sampling and multi-verifier ITS with ARW on a stronger open-source joint audio-video generation model. Top: ITS better reflects the intended piano-playing posture and interaction with the instrument. Bottom: ITS produces more distinct footstep events that better align with the walking motion. These examples suggest that ARW improves prompt￾faithful audiovi… view at source ↗
Figure 16
Figure 16. Figure 16: Failure cases. Top: Although the ITS framework generally improves the visual quality and text alignment, it still struggles with physical plausibility. For instance, the generated bird’s wing unnaturally passes through the solid feeder, indicating a lack of physical priors. Bottom: ITS successfully corrects semantic errors, such as guiding the horse to properly walk forward, unlike the naive sampling whic… view at source ↗
read the original abstract

Joint audio-video generation aims to synthesize realistic audio-video pairs that are both semantically aligned with text prompts and precisely synchronized. While existing joint audio-video generation models often require substantial training resources to improve fidelity, Inference-Time Scaling (ITS) has recently emerged as a promising training-free alternative in single-modality domains. However, extending ITS from a single modality to multimodal domains is non-trivial, as it requires balancing multiple heterogeneous objectives. In this paper, we present the first comprehensive study of ITS for joint audio-video generation. We first demonstrate that a multi-verifier framework is essential to address the limitations of single-objective guidance, including asymmetric performance trade-offs and verifier hacking. Through systematic analysis, we then identify an optimal multi-verifier combination that yields balanced improvements across all quality dimensions. Finally, to effectively aggregate diverse reward signals, we propose Adaptive Reward Weighting (ARW), a novel test-time optimization algorithm. ARW treats reward aggregation as an online optimization problem, utilizing learnable parameters to calibrate reward variances without requiring prior knowledge of reward distributions, thereby ensuring robust multi-objective selection. Experimental results on VGGSound and JavisBench-mini benchmarks demonstrate that our framework significantly enhances semantic alignment, perceptual quality, and audio-visual synchronization of generated outputs. Synthesized samples and code are available on the project page: https://jung-jaemin.github.io/ITS-AVGen-Proj.

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 paper conducts the first comprehensive study of Inference-Time Scaling (ITS) for joint audio-video generation. It argues that single-objective guidance leads to asymmetric performance trade-offs and verifier hacking, necessitating a multi-verifier framework. An optimal verifier combination is identified through systematic analysis, and Adaptive Reward Weighting (ARW) is introduced as a test-time optimization algorithm that treats reward aggregation as an online problem with learnable parameters to calibrate variances without prior distribution knowledge. Experiments on VGGSound and JavisBench-mini are claimed to show significant gains in semantic alignment, perceptual quality, and audio-visual synchronization.

Significance. If substantiated, this would represent a notable advance by extending training-free ITS methods to the multimodal AV domain, where balancing heterogeneous objectives is challenging. The ARW approach is a distinct contribution for distribution-agnostic reward aggregation via online learning. The release of code and samples supports reproducibility and allows direct verification of the framework.

major comments (2)
  1. [Abstract] Abstract: The central claim that 'our framework significantly enhances semantic alignment, perceptual quality, and audio-visual synchronization of generated outputs' is asserted without any quantitative results, metric values, baseline comparisons, ablation details, or error analysis. This directly undermines evaluation of whether the data support the empirical conclusions.
  2. [Abstract] Abstract: The assertion that 'a multi-verifier framework is essential' due to asymmetric trade-offs and verifier hacking is presented as demonstrated, but the systematic analysis, specific evidence, or data showing these limitations (and the optimality of the chosen combination) are not provided in the text.
minor comments (1)
  1. [Abstract] Abstract: The project page is referenced but without enumeration of available assets (e.g., specific generated samples, code release details, or benchmark subsets).

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the detailed feedback on the abstract. We agree that the abstract can be strengthened by incorporating key quantitative highlights and brief references to supporting analysis from the body of the paper. We will revise the abstract accordingly while preserving its summary nature. Below we respond to each major comment.

read point-by-point responses
  1. Referee: [Abstract] Abstract: The central claim that 'our framework significantly enhances semantic alignment, perceptual quality, and audio-visual synchronization of generated outputs' is asserted without any quantitative results, metric values, baseline comparisons, ablation details, or error analysis. This directly undermines evaluation of whether the data support the empirical conclusions.

    Authors: We acknowledge that the abstract presents high-level claims without specific numbers. The full manuscript provides these details in Section 4 (Experiments), including tables with metric values (e.g., improvements in semantic alignment, perceptual quality, and AV synchronization on VGGSound and JavisBench-mini), baseline comparisons, and ablations. To address the concern, we will revise the abstract to include concise quantitative highlights from the main results. revision_made: yes revision: yes

  2. Referee: [Abstract] Abstract: The assertion that 'a multi-verifier framework is essential' due to asymmetric trade-offs and verifier hacking is presented as demonstrated, but the systematic analysis, specific evidence, or data showing these limitations (and the optimality of the chosen combination) are not provided in the text.

    Authors: The abstract summarizes our finding that a multi-verifier framework is essential. The systematic analysis demonstrating asymmetric trade-offs, verifier hacking, and the optimal combination is presented in Section 3, supported by figures and tables. We will revise the abstract to briefly note the key evidence from this analysis (e.g., reference to observed trade-offs). revision_made: yes revision: yes

Circularity Check

0 steps flagged

No significant circularity; empirical framework validated by benchmarks

full rationale

The paper presents an empirical study of inference-time scaling for joint audio-video generation. It demonstrates limitations of single-objective guidance via analysis, identifies an optimal multi-verifier combination, and proposes ARW as a test-time optimization method using learnable parameters. All central claims (improved semantic alignment, perceptual quality, and synchronization) are supported by experimental results on VGGSound and JavisBench-mini benchmarks rather than any derivation chain. No equations, fitted predictions, self-citations, or ansatzes are described that reduce the outputs to the paper's own inputs by construction. The argument is self-contained against external benchmarks.

Axiom & Free-Parameter Ledger

1 free parameters · 0 axioms · 1 invented entities

Review performed on abstract only; full implementation details unavailable.

free parameters (1)
  • learnable parameters in ARW
    Used to calibrate reward variances during online optimization without prior knowledge of reward distributions
invented entities (1)
  • Adaptive Reward Weighting (ARW) no independent evidence
    purpose: Aggregate diverse reward signals from multiple verifiers as an online optimization problem
    Newly introduced test-time algorithm

pith-pipeline@v0.9.1-grok · 5787 in / 998 out tokens · 21237 ms · 2026-06-28T07:47:44.410494+00:00 · methodology

discussion (0)

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Reference graph

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    First,physical plausibility is still not guaranteed. In the upper example, ITS improves the overall prompt alignment by generating a hummingbird feeding from the feeder, but the bird’s wings still unrealistically pass through the feeder, indicating a violation of basic physics. Second,unstable temporal consistency remains an issue. In the lower example, n...