Investigating the Impact of Input Resolution on Object Detection Performance Using EfficientDet for Signature Detection in Document Images

Authors

  • Ensophea Toch School of Graduate Studies, Paragon International University, Phnom Penh, Cambodia Author
  • Pakrigna Long Department of Applied Mathematics and Statistics, Institute of Technology of Cambodia, Phnom Penh, Cambodia Author

Keywords:

signature detection, object detection, EfficientDet, BiFPN, input resolution, document image analysis

Abstract

Automated signature detection is a critical component of intelligent document processing systems, supporting document authentication and fraud detection. This paper presents a controlled empirical investigation of the effect of input resolution on handwritten signature detection using EfficientDet-D0. Three resolutions—512×512, 640×640, and 768×768—were evaluated under identical training conditions on a self-collected corpus of 1,000 annotated document images. Detection performance, measured by mAP@0.5, follows a non-monotonic trend: it improves from 0.9000 at 512×512 to a peak of 0.9261 at 640×640, then declines slightly to 0.9233 at 768×768, even though the 768×768 configuration achieves the lowest validation loss. We attribute this pattern to interacting effects of BiFPN feature granularity, anchor-scale alignment, and optimization complexity, and we discuss the scope and limitations of a single-architecture, single-run study. The results indicate that input resolution is a domain-specific hyperparameter that should be empirically tuned rather than inherited from benchmark conventions.

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Published

2026-11-02

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Articles

How to Cite

Investigating the Impact of Input Resolution on Object Detection Performance Using EfficientDet for Signature Detection in Document Images. (2026). Journal of Applied Mathematics, Informatics and Digital Arts, 1(1), 8-12. https://ojs.paragoniu.edu.kh/index.php/pjournal/article/view/22