Writing study: Spherical Watermark: Encryption-Free, Lossless Watermarking for Diffusion Models
← ICLR 2026 oral writing corpus
Xiaoxiao Hu, Jiaqi Jin, Sheng Li, Wanli Peng, Xinpeng Zhang, Zhenxing Qian · Official ICLR 2026 oral record
Figure, table and section ledger
Editorial contribution type: Inference, algorithms & systems efficiency (primary) · Theory & formal foundations.
Layout extraction, not a required paper template. Counts are distinct caption labels; a multi-panel figure counts once. Section spans are estimated from heading positions, including floats and whitespace. Method and limitations.
- Canonical PDF
- 33 physical pages
- Before references / appendix
- ≈ 10.45 page-equivalents
- Main figures / tables
- 6 / 5
- Attached appendix figures / tables
- 11 / 12
- Attached appendix span
- ≈ 18.31 page-equivalents
Section-by-section lengths and source pages
The title/abstract/front matter precede the first numbered heading. A span ends at the next detected top-level heading, not at the last sentence; end-page whitespace is included. References and statements are listed separately. These are not measurements of text-only or artwork area.
| Top-level heading | Starts on PDF page | Estimated span | Share of entire PDF |
|---|---|---|---|
| 1 INTRODUCTION | 1 | ≈ 0.89 pp. | 2.7% |
| 2 RELATED WORKS | 2 | ≈ 0.87 pp. | 2.64% |
| 3 METHOD | 3 | ≈ 3.23 pp. | 9.79% |
| 4 EXPERIMENT | 6 | ≈ 4.03 pp. | 12.21% |
| 5 DISCUSSION AND LIMITATIONS | 10 | ≈ 0.18 pp. | 0.55% |
| 6 CONCLUSION | 10 | ≈ 0.31 pp. | 0.94% |
| ACKNOWLEDGMENTS | 11 | ≈ 0.1 pp. | 0.3% |
| ETHICS STATEMENT | 11 | ≈ 0.11 pp. | 0.33% |
| REPRODUCIBILITY STATEMENT | 11 | ≈ 0.14 pp. | 0.42% |
| REFERENCES | 11 | ≈ 4.24 pp. | 12.85% |
| APPENDIX | 15 | ≈ 0.16 pp. | 0.48% |
| A USE OF LARGE LANGUAGE MODELS | 15 | ≈ 0.59 pp. | 1.79% |
| B OVERVIEW OF BASELINE METHODS | 16 | ≈ 0.92 pp. | 2.79% |
| C PROOFS OF THEOREMS AND LEMMAS IN SECTION 3.3 | 17 | ≈ 4.94 pp. | 14.97% |
| D ROLE OF ROTATION IN ENHANCING ROBUSTNESS | 22 | ≈ 1.8 pp. | 5.45% |
| E WHY LOSSLESSNESS MATTERS: AN DETECTOR-DRIVEN OPTIMIZATION | 24 | ≈ 1.51 pp. | 4.58% |
| F MORE DETAILS AND EXPERIMENTAL RESULTS | 25 | ≈ 8.38 pp. | 25.39% |
All detected figure and table locations
Main text
Attached appendix
- Figure 7 · p. 16
- Figure 8 · p. 25
- Table 6 · p. 25
- Table 7 · p. 25
- Figure 9 · p. 26
- Figure 10 · p. 26
- Table 8 · p. 27
- Table 9 · p. 27
- Table 10 · p. 28
- Table 11 · p. 28
- Figure 11 · p. 28
- Figure 12 · p. 29
- Figure 13 · p. 29
- Table 12 · p. 30
- Table 13 · p. 30
- Table 14 · p. 30
- Table 15 · p. 30
- Table 16 · p. 31
- Table 17 · p. 31
- Figure 14 · p. 31
- Figure 15 · p. 32
- Figure 16 · p. 33
- Figure 17 · p. 33
Argument and organization
- Provenance problem → invertible embedding pipeline
Separates offline signature construction from runtime generation and extraction.
- Theory → fidelity, tracing, speed → ablations
Groups evaluation around distinct promised benefits.
Argument and section order
The method first defines Embed/Extract and desired properties, then introduces three named modules whose symbols recur in the equations and ablations.
Sections 3.1–3.3, pages 3–6 · Main paper
Figures, captions and visual explanation
Figure 1 separates the deployment workflow from the algebraic pipeline and uses forward/backward arrows for embedding and extraction; the sphere drawings give a concrete meaning to the rotation step.
Figure 1, page 3 · Main paper
Tables, comparisons and evidence
Table 2 distinguishes bit accuracy from TPR at 1% FPR and separates clean, post-processing, and adversarial settings rather than compressing robustness into one score.
Table 2, page 8 · Main paper
The efficiency paragraph explicitly excludes diffusion generation and inversion from its timing; retaining that boundary prevents a watermark-decoder speedup being mistaken for end-to-end acceleration.
Figure 4 and Computational Efficiency, page 8 · Main paper
Appendix and reproducibility
The appendix has a navigational overview, then separates mathematical arguments from attack parameters and cross-backbone experiments; attack-strength details make the aggregate main table interpretable.
Appendix overview, page 15; Appendices C–F, pages 17–33 · Main paper
Clarity and writing conventions
The strong exact-Gaussian and indistinguishability language should be narrowed to the proved low-order moment properties and tested detectors: a fixed rotation of a finite spherical design is not a uniform continuous sphere.
Section 3.3, page 6; Section 5, page 10; Appendix C, pages 19–22 · Main paper
What to reuse—and what not to infer
Transferable lesson: Give each advertised property its own evaluation axis and disclose what is excluded from speed measurements directly beside the figure.
Boundary: Moment matching and near-chance performance of selected classifiers do not establish general cryptographic indistinguishability or exact joint Gaussianity. Fixed-key Gaussian Shading is also a deliberately altered baseline configuration.
Apply this lesson using the argument and evidence worksheet.
Inspection record and sources
- Checked
- 2026-09-19
- Reading status
- Full text + selected visuals inspected
- Main text
- Pages 1–11, Sections 1–6 and reproducibility statement; references through page 15
- Appendix / supplement
- Pages 15–33, Appendices A–F: baseline descriptions, proofs, channel analysis, threat-model argument, additional models and attacks
- Visually inspected PDF pages
- 3, 8
- ICLR 2026 final proceedings · 33 pages