Towards Electoral Digitization: Automatic Classification of Handwritten Numbers in PREP System Records

The digitization of electoral processes requires robust systems for processing handwritten numerical data from voting documents. This paper presents a convolutional neural network study for handwritten digit recognition in Mexico’s PREP (Programa de Resultados Electorales Preliminares) system. Rather than individual digit classification, we approach the problem as direct 1000-class classification, treating each three-digit combination as a single class to maximize accuracy and simplify inference. We evaluated eight CNN architectures including ResNet variants, MobileNetV3, ShuffleNetV2, and EfficientNet, with ResNet-18 emerging as optimal for balancing accuracy and computational efficiency under CPU-only deployment. To address dataset challenges including class imbalance and image artifacts, we developed a customized RandAugment strategy applying photometric and limited geometric transformations that preserve semantic integrity. Our methodology demonstrates feasibility of deploying robust digit recognition systems in resource-constrained electoral environments while maintaining high accuracy. The research provides a practical framework for automated electoral data processing adaptable to similar systems across Latin America.