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JACIII Vol.30 No.4 pp. 1306-1317
(2026)
doi: 10.20965/jaciii.2026.p1306

Research Paper:

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VPDL: Visual Prompt-Guided Differential Learning for Generalizable Scene Text Recognition

Yali Niu*, Jiahao An*,†, and Shihao Zou** ORCID Icon

*School of Transportation & Information, Shaanxi College of Communications Technology
No.19 Wenjing Road, Weiyang District, Xi’an, Shaanxi 710018, China

†Corresponding author

**School of Computer Science and Technology, Huazhong University of Science and Technology
No.1037 Luoyu Road, Hongshan District, Wuhan, Hubei 430074, China

Received:
December 5, 2025
Accepted:
April 2, 2026
Published:
July 20, 2026
Creative Commons License
Keywords:
scene text recognition, visual prompt learning, differential learning, textual prompts
Abstract

Scene text recognition (STR) in natural images remains highly challenging due to the large variations in character appearance across diverse real-world conditions, such as changes in font, color, layout, and background complexity—which hinder model generalization and remain insufficiently explored. To address this issue, we propose a visual prompt-guided differential learning (VPDL) framework designed to improve the generalization capability of STR models without requiring scene-specific fine-tuning. Inspired by the human ability to reference prior visual knowledge when recognizing text, VPDL introduces a set of character-level visual prompts that guide the model in perceiving appearance variations among characters. Built upon these prompts, we develop a local-to-global differential learning strategy that enhances patch-level representations and aligns global features with character cues while preserving scene-specific information. Additionally, to mitigate exposure bias in autoregressive decoding, we replace conventional label inputs with context-aware textual prompts, encouraging the decoder to better utilize textual cues embedded in image features. Extensive experiments on widely used benchmarks and real-world datasets demonstrate the effectiveness of VPDL.

Prompt-guided STR model

Prompt-guided STR model

Full text
Cite this article as:
Y. Niu, J. An, and S. Zou, “VPDL: Visual Prompt-Guided Differential Learning for Generalizable Scene Text Recognition,” J. Adv. Comput. Intell. Intell. Inform., Vol.30 No.4, pp. 1306-1317, 2026.
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