Research Article

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

by  Azam Nouri
journal cover
International Journal of Computer Applications
Foundation of Computer Science (FCS), NY, USA
Volume 187 - Issue 47
Published: October 2025
Authors: Azam Nouri
10.5120/ijca2025925791
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Azam Nouri . An MLP Baseline for Handwriting Recognition Using Planar Curvature and Gradient Orientation. International Journal of Computer Applications. 187, 47 (October 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 },
                        year    = { 2025 },
                        volume  = { 187 },
                        number  = { 47 },
                        pages   = { 1-5 },
                        doi     = { 10.5120/ijca2025925791 },
                        publisher = { Foundation of Computer Science (FCS), NY, USA }
                        }
                        %0 Journal Article
                        %D 2025
                        %A Azam Nouri
                        %T An MLP Baseline for Handwriting Recognition Using Planar Curvature and Gradient Orientation%T 
                        %J International Journal of Computer Applications
                        %V 187
                        %N 47
                        %P 1-5
                        %R 10.5120/ijca2025925791
                        %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
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Index Terms
Computer Science
Information Sciences
No index terms available.
Keywords

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

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