REVIEW 2 major objections 34 references
A latent diffusion model pretrained on English handwriting generates legible style-matched Ukrainian text after direct retraining on a new Cyrillic dataset.
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 18:42 UTC pith:4FYIUPK4
load-bearing objection The paper releases a new Ukrainian handwriting dataset and shows an unmodified DiffusionPen can be retrained on it for Cyrillic, but the evaluation stays purely qualitative. the 2 major comments →
Diffusion-Based Ukrainian Handwritten Text Generation with Cross-Domain Style Transfer
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
Retraining DiffusionPen on the constructed Ukrainian dataset without architectural changes yields legible, style-consistent word images in cross-lingual, zero-shot historical, and few-shot contemporary settings, showing that few-shot latent diffusion models generalize beyond the Latin-script domain.
What carries the argument
DiffusionPen, a MobileNetV2 triplet-loss style encoder paired with a CANINE-conditioned latent diffusion U-Net that encodes writer style and generates conditioned handwritten word images.
Load-bearing premise
The connected-component segmentation, quality filtering, and targeted oversampling steps create a representative unbiased dataset that permits successful direct retraining of the Latin-pretrained model on Cyrillic.
What would settle it
If the retrained model produces outputs that are largely illegible or fail to preserve target writer styles in the three evaluated transfer settings, the claim of successful generalization to Cyrillic would not hold.
If this is right
- Cross-lingual transfer from IAM English handwriting samples succeeds on the Ukrainian data.
- Zero-shot transfer generates usable images from an early 20th-century Ukrainian manuscript.
- Few-shot adaptation reproduces the styles of contemporary Ukrainian writers.
- No architectural modifications or extra adaptation techniques are required for the script change.
Where Pith is reading between the lines
- The same dataset-construction and direct-retraining approach could be tested on other non-Latin scripts such as Arabic or Devanagari.
- Handwriting style features captured by the encoder may prove largely independent of the underlying script alphabet.
- Smaller or less curated target-language datasets might still suffice if the Latin pretraining already supplies robust style priors.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript constructs a 126,177-image Ukrainian handwritten word dataset from 308 writers via connected-component segmentation, quality filtering, and oversampling of underrepresented characters. It retrains the DiffusionPen architecture (MobileNetV2 triplet-loss style encoder plus CANINE-conditioned latent diffusion U-Net) on this dataset with no architectural changes, then evaluates cross-domain style transfer in three regimes: cross-lingual transfer from IAM English, zero-shot transfer to an early-20th-century Ukrainian manuscript, and few-shot imitation of contemporary writers. The central claim is that the resulting generations are legible and style-consistent, demonstrating that few-shot latent diffusion models generalize beyond the Latin-script domain; the dataset, models, and evaluation protocol are released as a benchmark.
Significance. If the empirical results can be substantiated with quantitative evidence, the work would be significant for establishing the first large-scale writer-labeled Cyrillic HTG resource and for providing concrete evidence that a Latin-pretrained latent diffusion model can be directly retrained for a non-Latin script without architectural adaptation, thereby supporting broader claims about cross-domain generalization in few-shot generative models for handwriting.
major comments (2)
- [Abstract] Abstract and Evaluation section: the central claim that the model 'produces legible, style-consistent word images' is supported solely by qualitative description; no quantitative metrics (FID, character recognition accuracy, style similarity scores, human preference rates), baselines, or error analysis are reported, and no protocol is given for how legibility or style consistency were measured, making the claim impossible to verify or compare.
- [Dataset construction] Dataset construction (abstract and §3): the use of connected-component segmentation to produce word-level images is presented without any validation, statistics, or visual examples confirming that the resulting samples are intact words rather than fragmented strokes or characters; in cursive Cyrillic this is a known risk, and the absence of such checks is load-bearing because the retraining success and generalization claim presuppose a representative set of complete word images.
Simulated Author's Rebuttal
We thank the referee for the constructive feedback, which highlights important areas for strengthening the manuscript's claims. We address each major comment below and will revise the paper to incorporate quantitative evaluation and dataset validation details.
read point-by-point responses
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Referee: [Abstract] Abstract and Evaluation section: the central claim that the model 'produces legible, style-consistent word images' is supported solely by qualitative description; no quantitative metrics (FID, character recognition accuracy, style similarity scores, human preference rates), baselines, or error analysis are reported, and no protocol is given for how legibility or style consistency were measured, making the claim impossible to verify or compare.
Authors: We agree that the current presentation relies on qualitative assessment and lacks the quantitative support needed for verification and comparison. In the revised manuscript, we will add FID scores computed on generated vs. real images to quantify style consistency, character recognition accuracy via a fine-tuned OCR model to measure legibility, and style similarity scores derived from the MobileNetV2 encoder embeddings. We will also include a description of the evaluation protocol, relevant baselines (e.g., direct transfer without retraining), and basic error analysis. These additions will be placed in a new or expanded Evaluation section. revision: yes
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Referee: [Dataset construction] Dataset construction (abstract and §3): the use of connected-component segmentation to produce word-level images is presented without any validation, statistics, or visual examples confirming that the resulting samples are intact words rather than fragmented strokes or characters; in cursive Cyrillic this is a known risk, and the absence of such checks is load-bearing because the retraining success and generalization claim presuppose a representative set of complete word images.
Authors: We acknowledge that explicit validation of the connected-component segmentation step is necessary, particularly given the cursive nature of Ukrainian handwriting. In the revision, we will add: (i) statistics on word image dimensions, character counts per word, and writer distribution; (ii) visual examples of segmented word images in the main text or supplementary material; and (iii) results from a manual review of a random subset (e.g., 500 images) confirming that >95% represent complete words. These details will be incorporated into §3 to substantiate the dataset quality. revision: yes
Circularity Check
No circularity: purely empirical retraining and evaluation
full rationale
The paper constructs a Ukrainian word dataset via connected-component segmentation, quality filtering and oversampling, then retrains the existing DiffusionPen architecture without modification and reports visual style-transfer results on cross-lingual, zero-shot and few-shot settings. No equations, derivations, fitted parameters or predictions appear in the provided text; the central claim is an empirical observation about output legibility rather than any quantity shown to equal its own inputs by construction. No self-citation chains or uniqueness theorems are invoked to justify the method. The work is therefore self-contained against external benchmarks and receives the default non-circularity finding.
Axiom & Free-Parameter Ledger
axioms (2)
- domain assumption The pre-trained DiffusionPen architecture requires no modification to adapt from Latin to Cyrillic handwritten text generation.
- domain assumption Connected-component segmentation combined with quality filtering and oversampling yields a high-quality, unbiased training set for Ukrainian words.
read the original abstract
Handwritten text generation (HTG) conditioned on writer style has been widely studied for Latin scripts, but remains underexplored for low-resource and non-Latin writing systems, leaving open how well existing models generalise beyond the Latin domain. Cyrillic, particularly Ukrainian, lacks both large-scale writer-labeled datasets and empirical evidence of such generalisation. To address this gap, we construct a Ukrainian handwritten word dataset of 126,177 images from 308 writers using connected-component segmentation, quality filtering, and targeted oversampling of underrepresented Ukrainian characters. We retrain DiffusionPen, a MobileNetV2 triplet-loss style encoder with a CANINE-conditioned latent diffusion U-Net, on this dataset without architectural modification, testing direct transfer from Latin to Cyrillic. We evaluate cross-domain style transfer in three settings: cross-lingual transfer from IAM English samples, zero-shot transfer to an early 20th-century Ukrainian manuscript, and few-shot imitation of contemporary writers. The model produces legible, style-consistent word images, indicating that few-shot latent diffusion models generalize beyond the Latin-script domain. We release the dataset, trained models, and evaluation protocol as a reproducible benchmark for writer-aware Cyrillic HTG, providing a foundation for extending stylized HTG to other underrepresented writing systems.
Figures
Reference graph
Works this paper leans on
-
[1]
In: International Conference on Document Anal- ysis and Recognition (2019)
Alonso, E., Moysset, B., Messina, R.: Adversarial generation of handwritten text images conditioned on sequences. In: International Conference on Document Anal- ysis and Recognition (2019)
2019
-
[2]
In: Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR)
Baek, Y., Lee, B., Han, D., Yun, S., Lee, H.: Character region awareness for text detection. In: Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR). pp. 9365–9374 (2019).https://doi.org/10.1109/ CVPR.2019.00959
-
[3]
In: Proceedings of the IEEE/CVF International Conference on Com- puter Vision (ICCV) (2021)
Bhunia, A.K., Khan, S., Cholakkal, H., Anwer, R.M., Khan, F.S.: Handwriting transformers. In: Proceedings of the IEEE/CVF International Conference on Com- puter Vision (ICCV) (2021)
2021
-
[4]
Bradski, G.: The OpenCV library. Dr. Dobb’s Journal of Software Tools (2000)
2000
-
[5]
Central State Historical Archives of Ukraine: Digitised manuscript, fund 423, file 723996 (2026),https://archium.tsdial.archives.gov.ua/file-viewer/ 232981#file-723996
2026
-
[6]
In: Proceedings of the European Conference on Computer Vision (ECCV) (2022)
Chen, L., Chu, X., Zhang, X., Sun, J.: Simple baselines for image restoration. In: Proceedings of the European Conference on Computer Vision (ECCV) (2022)
2022
-
[7]
Transactions of the Associ- ation for Computational Linguistics10, 73–91 (2022)
Clark, J.H., Garrette, D., Turc, I., Wieting, J.: CANINE: Pre-training an efficient tokenization-free encoder for language representation. Transactions of the Associ- ation for Computational Linguistics10, 73–91 (2022)
2022
-
[8]
In: European Conference on Computer Vi- sion (2024)
Dai, G., Zhang, Y., Ke, Q., Guo, Q., Huang, S.: One-dm: One-shot diffusion mim- icker for handwritten text generation. In: European Conference on Computer Vi- sion (2024)
2024
-
[9]
In: IEEE/CVF International Conference on Computer Vision (2025)
Dai, G., et al.: Beyond isolated words: Diffusion brush for handwritten text-line generation. In: IEEE/CVF International Conference on Computer Vision (2025)
2025
-
[10]
In: Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR) (2020)
Fogel, S., Averbuch-Elor, H., Cohen, S., Mazor, S., Litman, R.: ScrabbleGAN: Semi-supervised varying length handwritten text generation. In: Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR) (2020)
2020
-
[11]
In: Proceedings of the AAAI Conference on Artificial Intelligence (2021)
Gan,J.,Wang,W.:HiGAN:Handwritingimitationconditionedonarbitrary-length texts and disentangled styles. In: Proceedings of the AAAI Conference on Artificial Intelligence (2021)
2021
-
[12]
In: Advances in Neural Information Processing Systems (NeurIPS)
Heusel, M., Ramsauer, H., Unterthiner, T., Nessler, B., Hochreiter, S.: GANs trained by a two time-scale update rule converge to a local nash equilibrium. In: Advances in Neural Information Processing Systems (NeurIPS). vol. 30 (2017)
2017
-
[13]
Hnatiuk, A.: Ukrainian handwritten text (2022),https://www.kaggle.com/ datasets/annyhnatiuk/ukrainian-handwritten-text
2022
-
[14]
In: NeurIPS 2021 Workshop on Deep Generative Models and Downstream Applications (2021)
Ho, J., Salimans, T.: Classifier-free diffusion guidance. In: NeurIPS 2021 Workshop on Deep Generative Models and Downstream Applications (2021)
2021
-
[15]
PeerJ Computer Science (2022)
Jemni, S.K., et al.: Generative adversarial network based adaptive data augmen- tation for handwritten arabic text recognition. PeerJ Computer Science (2022)
2022
-
[16]
In: Proceedings of the European Conference on Computer Vision (ECCV) (2020)
Kang, L., Riba, P., Rusi˜ nol, M., Forn´ es, A., Villegas, M.: GANwriting: Content- conditioned generation of styled handwritten word images. In: Proceedings of the European Conference on Computer Vision (ECCV) (2020)
2020
-
[17]
In: Advances in Neural Information Processing Systems (NeurIPS)
Krizhevsky, A., Sutskever, I., Hinton, G.E.: ImageNet classification with deep con- volutional neural networks. In: Advances in Neural Information Processing Systems (NeurIPS). vol. 25 (2012)
2012
-
[18]
In: Proceedings of the AAAI Conference on Artificial Intelligence (2023)
Li, M., Lv, T., Chen, J., Cui, L., Lu, Y., Florencio, D., Zhang, C., Li, Z., Wei, F.: TrOCR: Transformer-based optical character recognition with pre-trained models. In: Proceedings of the AAAI Conference on Artificial Intelligence (2023)
2023
-
[19]
International Journal on Document Analysis and Recognition5(1), 39–46 (2002)
Marti, U.V., Bunke, H.: The IAM-database: An english sentence database for of- fline handwriting recognition. International Journal on Document Analysis and Recognition5(1), 39–46 (2002)
2002
-
[20]
In: Proceedings of the International Con- ference on Document Analysis and Recognition (ICDAR)
Nikolaidou, K., Retsinas, G., Christlein, V., Seuret, M., Sfikas, G., Barney Smith, E.H., Mokayed, H., Liwicki, M.: WordStylist: Styled verbatim handwritten text generation with latent diffusion models. In: Proceedings of the International Con- ference on Document Analysis and Recognition (ICDAR). Lecture Notes in Com- puter Science, vol. 14188 (2023)
2023
-
[21]
arXiv preprint arXiv:2508.17017 (2025)
Nikolaidou, K., Retsinas, G., Sfikas, G., Cascianelli, S., Cucchiara, R., Liwicki, M.: Dual orthogonal guidance for robust diffusion-based handwritten text generation. arXiv preprint arXiv:2508.17017 (2025)
-
[22]
In: Proceedings of the European Conference on Computer Vision (ECCV) (2024)
Nikolaidou, K., Retsinas, G., Sfikas, G., Liwicki, M.: DiffusionPen: Towards con- trolling the style of handwritten text generation. In: Proceedings of the European Conference on Computer Vision (ECCV) (2024)
2024
-
[23]
IEEE Trans- actions on Systems, Man, and Cybernetics9(1), 62–66 (1979)
Otsu, N.: A threshold selection method from gray-level histograms. IEEE Trans- actions on Systems, Man, and Cybernetics9(1), 62–66 (1979)
1979
-
[24]
In: Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR) (2023)
Pippi, V., Cascianelli, S., Cucchiara, R.: Handwritten text generation from visual archetypes. In: Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR) (2023)
2023
-
[25]
arXiv preprint arXiv:2407.15608 (2024)
Riaz, N., Saifullah, S., Agne, S., Dengel, A., Ahmed, S.: StylusAI: Stylis- tic adaptation for robust German handwritten text generation. arXiv preprint arXiv:2407.15608 (2024)
-
[26]
In: Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR)
Rombach, R., Blattmann, A., Lorenz, D., Esser, P., Ommer, B.: High-resolution image synthesis with latent diffusion models. In: Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR). pp. 10684– 10695 (2022)
2022
-
[27]
Rombach, R., Blattmann, A., Lorenz, D., Esser, P., Ommer, B.: Stable diffusion v1- 5.https://huggingface.co/stable-diffusion-v1-5/stable-diffusion-v1-5 (2022)
2022
-
[28]
In: Medical Image Computing and Computer-Assisted Intervention (MICCAI)
Ronneberger, O., Fischer, P., Brox, T.: U-Net: Convolutional networks for biomed- ical image segmentation. In: Medical Image Computing and Computer-Assisted Intervention (MICCAI). pp. 234–241 (2015)
2015
-
[29]
In: Proceedings of the IEEE/CVF Confer- ence on Computer Vision and Pattern Recognition (CVPR) (2018)
Sandler, M., Howard, A., Zhu, M., Zhmoginov, A., Chen, L.C.: MobileNetV2: In- verted residuals and linear bottlenecks. In: Proceedings of the IEEE/CVF Confer- ence on Computer Vision and Pattern Recognition (CVPR) (2018)
2018
-
[30]
Facenet: A unified embedding for face recognition and clustering,
Schroff, F., Kalenichenko, D., Philbin, J.: FaceNet: A unified embedding for face recognition and clustering. In: Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition (CVPR). pp. 815–823 (2015).https://doi.org/ 10.1109/CVPR.2015.7298682
-
[31]
Song,J.,Meng,C.,Ermon,S.:Denoisingdiffusionimplicitmodels.In:International Conference on Learning Representations (ICLR) (2021)
2021
-
[32]
IEEE Transactions on Pattern Analysis and Machine Intelligence (2024)
Vanherle, B., Pippi, V., Cascianelli, S., Michiels, N., Van Reeth, F., Cucchiara, R.: VATr++: Choose your words wisely for handwritten text generation. IEEE Transactions on Pattern Analysis and Machine Intelligence (2024)
2024
-
[33]
Voitekh, D., Zmiivskyyi, V., Molchanovskyi, O.: RUKOPYS: Ukrainian handwritten text recognition dataset (2026),https://huggingface.co/ UkrainianCatholicUniversity/rukopys, first large-scale Ukrainian HTR dataset; from 1920s archival documents to 2025 school homework and exams
2026
-
[34]
In: Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition (CVPR) (2018)
Zhang, R., Isola, P., Efros, A.A., Shechtman, E., Wang, O.: The unreasonable effectiveness of deep features as a perceptual metric. In: Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition (CVPR) (2018)
2018
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