Pith. sign in

REVIEW 2 major objections 2 minor 14 references

DV-SFT labels each visual token with the word from its image patch and applies next-token prediction to those tokens directly.

Reviewed by Pith at T0; open to challenge. T0 means a machine referee read the full paper against a public rubric. the ladder, T0–T4 →

T0 review · grok-4.3

2026-06-29 17:58 UTC pith:XT6F5IMD

load-bearing objection DV-SFT adds direct next-token supervision to visual tokens via OCR patch-to-word labels without extra modules, but the text-only nature of the labels leaves the claimed gains on general fine-grained visual tasks unconvincing. the 2 major comments →

arxiv 2605.26656 v1 pith:XT6F5IMD submitted 2026-05-26 cs.CV

DV-SFT: Direct Vision Supervision for Fine-Grained Visual Understanding

classification cs.CV
keywords multimodal large language modelsvisual token supervisionfine-grained visual understandingOCR-based labelingnext-token predictionsupervised fine-tuningmultimodal alignment
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved

The pith

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

Multimodal models currently receive supervision only on text tokens, leaving visual tokens to be optimized only as context and producing coarse visual understanding. The paper constructs explicit labels for visual tokens by matching each one to the word appearing in its corresponding image patch through OCR correspondence. These labeled visual tokens are then trained with the identical next-token prediction loss used for text, all without changing the model architecture or adding extra passes. The method produces stronger results on both in-domain and out-of-domain benchmarks and raises the efficiency of vision-language alignment.

Core claim

DV-SFT constructs explicit, token-level supervision for visual tokens by exploiting the direct vision-text correspondence in OCR-related scenarios, automatically labeling each visual token with the word in its corresponding image patch, and trains them through the same next-token prediction objective used for text while treating the MLLM as a black box that requires no architectural modifications or additional forward passes.

What carries the argument

Automatic assignment of OCR-derived word labels to individual visual tokens so they participate in the standard next-token prediction loss.

Load-bearing premise

The word labels taken from OCR matches on image patches supply effective supervision signals for fine-grained visual understanding in tasks that go beyond OCR itself.

What would settle it

Running DV-SFT on a suite of fine-grained visual benchmarks that contain no readable text and observing no improvement over ordinary SFT would show the method does not generalize.

Watch this falsifier — get emailed when new claim-graph text bears on it.

If this is right

  • DV-SFT outperforms standard SFT on three in-domain and four out-of-domain benchmarks.
  • Vision supervision improves fine-grained visual understanding.
  • The approach raises multimodal alignment efficiency.
  • No architectural changes or extra forward passes are required.

Where Pith is reading between the lines

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

  • If similar direct correspondences between visual patches and discrete labels can be obtained in non-text domains, the same supervision pattern could be applied without OCR.
  • The black-box nature suggests the technique could be combined with existing instruction-tuning pipelines at low additional cost.
  • The efficiency gain in alignment may reduce the volume of text-only data needed to reach a given level of visual performance.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit.

Referee Report

2 major / 2 minor

Summary. The paper proposes DV-SFT, a method that constructs explicit token-level supervision for visual tokens in multimodal LLMs by automatically labeling each visual token with the OCR word from its corresponding image patch and training via the standard next-token prediction objective. It claims this approach, which requires no architectural changes or extra forward passes, consistently outperforms standard SFT on three in-domain and four out-of-domain benchmarks while enhancing fine-grained visual understanding and multimodal alignment efficiency.

Significance. If the empirical claims hold under proper controls, the work offers a lightweight way to apply direct supervision to visual tokens using existing OCR pipelines, addressing the implicit optimization of visual representations in standard SFT without auxiliary decoders. This could improve practical applicability for fine-grained multimodal tasks.

major comments (2)
  1. [Method] The central mechanism relies on OCR-derived word labels for visual tokens (§3, method description). No explicit mechanism is provided showing how next-token prediction on these text strings produces richer non-textual visual features (e.g., object parts, textures, or spatial relations) needed for the claimed gains on out-of-domain benchmarks that need not contain readable text; the gradients appear confined to textual recognition.
  2. [Experiments] The abstract and results claim consistent outperformance on four out-of-domain benchmarks, yet the provided description supplies no dataset details, controls for OCR quality, error bars, or ablation isolating the contribution of vision supervision versus other factors (e.g., training schedule). This makes it impossible to verify whether the reported gains support the fine-grained understanding claim.
minor comments (2)
  1. Notation for visual token labeling and the exact loss formulation should be formalized with equations to clarify how the supervision is applied without modifying the MLLM architecture.
  2. The abstract would benefit from naming the specific in-domain and out-of-domain benchmarks and reporting quantitative improvements (e.g., accuracy deltas) rather than qualitative statements.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the constructive feedback. We address the two major comments point-by-point below and describe the revisions we will make.

read point-by-point responses
  1. Referee: [Method] The central mechanism relies on OCR-derived word labels for visual tokens (§3, method description). No explicit mechanism is provided showing how next-token prediction on these text strings produces richer non-textual visual features (e.g., object parts, textures, or spatial relations) needed for the claimed gains on out-of-domain benchmarks that need not contain readable text; the gradients appear confined to textual recognition.

    Authors: The next-token prediction objective is applied to each visual token using its corresponding OCR word as the target. This directly supervises the visual token's hidden state to encode the information necessary to predict the word from its image patch, updating the vision encoder and projector via backpropagation. While labels are textual, the resulting representations capture fine-grained patch content that improves multimodal alignment and transfers to out-of-domain tasks. We agree a clearer explanation of this gradient pathway and its effect on non-textual features is needed; we will add a dedicated paragraph with gradient analysis in the revised Section 3. revision: partial

  2. Referee: [Experiments] The abstract and results claim consistent outperformance on four out-of-domain benchmarks, yet the provided description supplies no dataset details, controls for OCR quality, error bars, or ablation isolating the contribution of vision supervision versus other factors (e.g., training schedule). This makes it impossible to verify whether the reported gains support the fine-grained understanding claim.

    Authors: The full manuscript contains dataset descriptions in Section 4, but we acknowledge the initial version lacked sufficient detail. In revision we will expand the experimental section with: explicit descriptions and sources for the four out-of-domain benchmarks, error bars from at least three random seeds, OCR quality controls (e.g., precision/recall of the labeling pipeline), and new ablations that isolate DV-SFT from training schedule and data volume. These additions will directly support the fine-grained understanding claims. revision: yes

Circularity Check

0 steps flagged

No circularity: method constructs labels from OCR and reports empirical gains without reduction to fitted inputs or self-citations

full rationale

The paper defines DV-SFT by constructing visual-token labels directly from OCR word-patch correspondences and applies the standard next-token prediction loss; performance claims rest on reported benchmark comparisons rather than any equation or parameter that is defined in terms of the target result. No self-citation is invoked as a uniqueness theorem or load-bearing premise, and the derivation does not rename a known pattern or smuggle an ansatz. The central claim therefore remains independent of its own inputs.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The central claim rests on the domain assumption that OCR scenarios supply reliable vision-text correspondences for token labeling. No free parameters, additional axioms, or invented entities are mentioned in the abstract.

axioms (1)
  • domain assumption Direct vision-text correspondence exists in OCR-related scenarios allowing automatic labeling of visual tokens with words from image patches.
    This premise enables generation of explicit supervision signals without manual annotation or auxiliary models.

pith-pipeline@v0.9.1-grok · 5763 in / 1223 out tokens · 48047 ms · 2026-06-29T17:58:27.797234+00:00 · methodology

0 comments
read the original abstract

Multimodal large language models are typically trained end-to-end to predict ground-truth answers, yet supervision signals are applied exclusively to text tokens. Visual tokens, the core carriers of visual information, are optimized only implicitly as part of the context, leading to coarse-grained visual understanding. Prior works attempt to supervise visual inputs but inevitably rely on auxiliary components such as additional decoders or forward passes, because visual tokens lack readily interpretable labels. This limits their practical applicability. In this work, we propose \textbf{D}irect \textbf{V}ision \textbf{S}upervised \textbf{F}ine-\textbf{T}uning (DV-SFT), which constructs explicit, token-level supervision for visual tokens and trains them through the same next-token prediction objective used for text. Specifically, we exploit the direct vision--text correspondence in OCR-related scenarios and automatically label each visual token with the word in its corresponding image patch. DV-SFT treats the MLLM as a black box, requiring no architectural modifications or additional forward passes. Extensive experiments demonstrate the superiority of direct vision supervision. DV-SFT consistently outperforms standard SFT across three in-domain and four out-of-domain benchmarks. Further analyses show that vision supervision effectively enhances fine-grained visual understanding and achieves higher multimodal alignment efficiency.

Figures

Figures reproduced from arXiv: 2605.26656 by Bing Wang, Chong Feng, Feng Zhang, Jianfei Zhao, Xin Sun, Zhixing Tan.

Figure 2
Figure 2. Figure 2: Diagram of DV-SFT. The training procedure [PITH_FULL_IMAGE:figures/full_fig_p003_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: Test results of Qwen3-1.7B at each checkpoint [PITH_FULL_IMAGE:figures/full_fig_p006_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: Test results on naive text OCR tasks. Contextual OCR refers to the recognition task on normal text, while Non-Contextual OCR refers to the recognition task on unordered word sequences. NED denotes Normalized Edit Distance, where lower values indicate better performance. Left part: test results at the original image resolution. Right part: test results of the 2B model at different image resolutions, with th… view at source ↗
Figure 5
Figure 5. Figure 5: A case study of visual logits in a general [PITH_FULL_IMAGE:figures/full_fig_p007_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: Ablation studies on the validation set of [PITH_FULL_IMAGE:figures/full_fig_p008_6.png] view at source ↗
Figure 7
Figure 7. Figure 7: Format-control instructions. Qwen3-VL-2B / Qwen3-1.7B Min Pixels 32*32*64 Max Pixels 32*32*2048 Global Batch Size 64 Learning Rate 5e-6 Warmup Ratio 0.03 Max Grad Norm 1 LR Scheduler cosine Weight Decay 0 Model Max Length 8192 Additional Settings for Qwen3-VL-8B Learning Rate 2e-5 LoRA Rank 64 LoRA Alpha 128 LoRA Dropout 0 [PITH_FULL_IMAGE:figures/full_fig_p011_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: An example of constructing vision labels by the image-to-label approach. Each rectangle represents a [PITH_FULL_IMAGE:figures/full_fig_p013_8.png] view at source ↗
Figure 9
Figure 9. Figure 9: An example of constructing vision labels by the label-to-image approach. The grid represents the vision [PITH_FULL_IMAGE:figures/full_fig_p013_9.png] view at source ↗

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

14 extracted references · 2 canonical work pages

  1. [1]

    arXiv preprint arXiv:2311.16479 (2023) 16 Lei et al

    Mitigating hallucination in visual language models with visual supervision.arXiv preprint arXiv:2311.16479. Cheng Cui, Ting Sun, Manhui Lin, Tingquan Gao, Yubo Zhang, Jiaxuan Liu, Xueqing Wang, Zelun Zhang, Changda Zhou, Hongen Liu, et al. 2025. Paddleocr 3.0 technical report.arXiv preprint arXiv:2507.05595. Wenliang Dai, Junnan Li, Dongxu Li, Anthony Tio...

  2. [2]

    InEMNLP, pages 1797–1807

    Don’t give me the details, just the summary! topic-aware convolutional neural networks for ex- treme summarization. InEMNLP, pages 1797–1807. Pranav Rajpurkar, Jian Zhang, Konstantin Lopyrev, and Percy Liang. 2016. Squad: 100,000+ questions for machine comprehension of text. InEMNLP, pages 2383–2392. Amanpreet Singh, Vivek Natarjan, Meet Shah, Yu Jiang, X...

  3. [3]

    arXiv preprint arXiv:2506.09040 , year=

    Basic: Boosting visual alignment with intrin- sic refined embeddings in multimodal large language models. InICCV, pages 20582–20592. Dianyi Wang, Wei Song, Yikun Wang, Siyuan Wang, Kaicheng Yu, Zhongyu Wei, and Jiaqi Wang. 2025a. Autoregressive semantic visual reconstruc- tion helps vlms understand better.arXiv preprint arXiv:2506.09040. Haochen Wang, Anl...

  4. [4]

    Answer the question using a single word or phrase

  5. [5]

    Respond with only the answer, no explanation

  6. [6]

    G ive a concise answer in one word or short phrase

  7. [7]

    Output only the answer, nothing else

  8. [8]

    Reply with a single word or phrase, no full sentences

  9. [9]

    Provide the answer as a single word or brief phrase

  10. [10]

    Provide a brief answer without additional text

  11. [11]

    K eep your response to a single word or short phrase

  12. [12]

    State the answer concisely in a word or phrase

  13. [13]

    Instructions Figure 7: Format-control instructions

    No explanations―just the answer word or phrase. Instructions Figure 7: Format-control instructions. Qwen3-VL-2B / Qwen3-1.7B Min Pixels 32*32*64 Max Pixels 32*32*2048 Global Batch Size 64 Learning Rate 5e-6 Warmup Ratio 0.03 Max Grad Norm 1 LR Scheduler cosine Weight Decay 0 Model Max Length 8192 Additional Settings for Qwen3-VL-8B Learning Rate 2e-5 LoRA...

  14. [14]

    method. This approach constructs supervi- sory signals from the hidden states of visual to- kens in the early-to-middle layers of the model and trains the projector and the first layer of the model to learn visual features through representation su- pervision. To ensure compatibility with FlashAt- tention, we disable the attention-distribution-based loss ...