CFP last date
22 December 2025
Call for Paper
January Edition
IJCA solicits high quality original research papers for the upcoming January edition of the journal. The last date of research paper submission is 22 December 2025

Submit your paper
Know more
Random Articles
Reseach Article

An MLP Baseline for Handwriting Recognition using Planar Curvature and Gradient Orientation

by Azam Nouri
International Journal of Computer Applications
Foundation of Computer Science (FCS), NY, USA
Volume 187 - Number 47
Year of Publication: 2025
Authors: Azam Nouri
10.5120/ijca2025925791

Azam Nouri . An MLP Baseline for Handwriting Recognition using Planar Curvature and Gradient Orientation. International Journal of Computer Applications. 187, 47 ( Oct 2025), 1-5. DOI=10.5120/ijca2025925791

@article{ 10.5120/ijca2025925791,
author = { Azam Nouri },
title = { An MLP Baseline for Handwriting Recognition using Planar Curvature and Gradient Orientation },
journal = { International Journal of Computer Applications },
issue_date = { Oct 2025 },
volume = { 187 },
number = { 47 },
month = { Oct },
year = { 2025 },
issn = { 0975-8887 },
pages = { 1-5 },
numpages = {9},
url = { https://ijcaonline.org/archives/volume187/number47/an-mlp-baseline-for-handwriting-recognition-using-planar-curvature-and-gradient-orientation/ },
doi = { 10.5120/ijca2025925791 },
publisher = {Foundation of Computer Science (FCS), NY, USA},
address = {New York, USA}
}
%0 Journal Article
%1 2025-10-23T00:18:06.622975+05:30
%A Azam Nouri
%T An MLP Baseline for Handwriting Recognition using Planar Curvature and Gradient Orientation
%J International Journal of Computer Applications
%@ 0975-8887
%V 187
%N 47
%P 1-5
%D 2025
%I Foundation of Computer Science (FCS), NY, USA
Abstract

This study investigates whether second-order geometric cues—planar curvature magnitude, curvature sign, and gradient orientation—are sufficient on their own to drive a multilayer perceptron (MLP) classifier for handwritten character recognition (HCR), offering an interpretable alternative to convolutional neural networks (CNNs). Using these three handcrafted feature maps as inputs, the curvature–orientation MLP achieves 97%accuracy on MNIST digits and 89%on EMNIST letters. These results underscore the discriminative power of curvature-based representations for handwritten character images and demonstrate that competitive performance is achievable with lightweight, explicitly engineered features.

References
  1. Cohen, G., Afshar, S., Tapson, J., and van Schaik, A. 2017. EMNIST: An Extension of MNIST to Handwritten Letters. arXiv preprint arXiv:1702.05373.
  2. Goldman, R. 2005. Curvature Formulas for Implicit Curves and Surfaces. Computer Aided Geometric Design, 22(7), 632–658.
  3. Kreyszig, E. 1991. Differential Geometry. Dover Publications.
  4. LeCun, Y., Bottou, L., Bengio, Y., and Haffner, P. 1998. Gradient-Based Learning Applied to Document Recognition. Proceedings of the IEEE, 86(11), 2278–2324.
  5. Nouri, A. 2025. A Sobel-Gradient MLP Baseline for Handwritten Character Recognition. arXiv:2508.11902.
  6. Nouri, A. 2025. Curvature-MLP: Code and Training Scripts (v1.0). Zenodo. DOI: 10.5281/zenodo.16934394.
  7. Siddiqi, I. I., and O’Connor, N. E. 2009. Combining Contour- Based Orientation and Curvature Features for Writer Recognition. In Proc. IWSSIP, 1–4.
  8. Sobel, I., and Feldman, G. 1968. An Isotropic 3×3 Image Gradient Operator. SAIL Technical Report, Stanford University.
  9. Srikantan, G., Lam, S. W., and Srihari, S. N. 1996. Gradient- Based Contour Encoding for Character Recognition. Pattern Recognition, 29(7), 1147–1160.
  10. TensorFlow Datasets Contributors. 2025. Tensor- Flow Datasets (Version 4.9.2). Available at: https: //www.tensorflow.org/datasets.
  11. Ou, B. 2009. Curvature Function in the Recognition of People’s Handwriting. International Journal of Pure and Applied Mathematics, 52(4), 575–581.
  12. Zhang, X., and Li, Y. 2023. Learnable Sobel Operators for Edge-Aware Feature Extraction in Convolutional Neural Networks. IEEE Access, 11, 12345–12358.
  13. Zhang, X., Zhou, Y., and Wu, Y. 2019. Edge Enhancement Network with Learnable Filters for Image Super-Resolution. In Proc. IEEE ICIP, 900–904.
Index Terms

Computer Science
Information Sciences

Keywords

Handwritten recognition; planar curvature; gradient orientation; multilayer perceptron; MNIST; EMNIST