Medical Applications -- Predicting the use of Invasive Mechanical Ventilation in ICU COVID-19 patients -- A Coarse to Fine Corneal Ulcer Segmentation Approach using U-net and DexiNed in Chain -- Replacing Data Augmentation with Rotation-equivariant CNNs in Image-based Classification of Oral Cancer -- A Multitasking Learning Framework for Dermoscopic Image Analysis -- An Evaluation of Segmentation Techniques for COVID-19 Identification in Chest X-Ray -- A Study on Annotation Efficient Learning Methods for Segmentation in Prostate Histopathological Images -- Natural Language Processing -- Data-Augmented Emoji Approach to Sentiment Classification of Tweets -- Detecting Hate Speech in Cross-Lingual and Multi-Lingual Settings Using Language Agnostic Representations -- Prediction of Perception of Security Using Social Media Content -- Metaheuristics -- Fine-Tuning Dropout Regularization in Energy-Based Deep Learning -- Enhancing Hyper-To-Real Space Projections Through Euclidean NormMeta-Heuristic Optimization -- Using Particle Swarm Optimization With Gradient Descent For Parameter Learning In Convolutional Neural Networks -- Image Segmentation -- Object Delineation by Iterative Dynamic Trees -- Low-Cost Domain Adaptation for Crop and Weed Segmentation -- Databases -- MIGMA: The Facial Emotion Image Dataset forHuman Expression Recognition -- Construction of Brazilian Regulatory Traffic Sign Recognition Dataset -- Japanese Kana and Brazilian Portuguese manuscript database -- Skelibras: a Large 2d Skeleton Dataset of Dynamic Brazilian Signs -- Deep Learning -- Cricket Scene Analysis using the RetinaNet architecture. -Texture-Based Image Transformations for Improved Deep Learning Classification -- Towards Precise Recognition of Pollen Bearing Bees by Convolutional Neural Networks -- Web Application Attacks Detection Using Deep Learning -- Less is More: Accelerating Faster Neural Networks Straight from JPEG -- Optimizing Person Re-Identification using GeneratedAttention Masks -- Self-Supervised Bernoulli Autoencoders for Semi-Supervised Hashing -- Explainable Artificial Intelligence -- Interpretable Concept Drift -- Interpreting a Conditional Generative Adversarial Network Model for Crime Prediction -- Interpreting Decision Patterns in Financial Applications -- Image Processing -- Metal Artifact Reduction based on color mapping and inpainting techniques -- New Improvement in Obtaining Monogenic Phase Congruency -- Machine Learning -- Evaluating the Construction of Feature Descriptors in the Performance of the Image Data Stream Classification -- Clustering-based Partitioning of Water Distribution Networks for Leak Zone Location -- Bias Quantification for Protected Features in Pattern Classification Problems -- Regional Commodities Price Volatility Assessment Using Self-Driven Recurrent Networks -- Semi-supervised Deep Learning Based on Label Propagation in a 2D Embedded Space -- Iterative Creation of Matching-Graphs - Finding Relevant Substructures in Graph Sets -- Semi-Autogeonous (SAG) Mill Overload Forecasting -- Novel Time-Frequency Based Scheme for Detecting Sound Events from Sound Background in Audio Segments -- Computer Vision -- Generalized Conics with the Sharp Corners -- Automatic Face Mask Detection using a Hide and Seek Algorithm -- A Feature Extraction Approach Based on LBP Operator and Complex Networks for Face Recognition -- End-to-End Deep Sketch-to-Photo Matching Enforcing Realistic Photo Generation -- Forensic Analysis of Tampered Digital Photos -- COVID-19 Lung CT Images Recognition: A Feature-Based Approach -- A Topologically Consistent Color Digital Image Representation by a Single Tree.

This book constitutes the proceedings of the 25th Iberoamerican Congress on Progress in Pattern Recognition, Image Analysis, Computer Vision, and Applications, CIARP 2021, which took place during May 10-13, 2021. The conference was initially planned to take place in Porto, Portugal, but changed to a virtual event due to the COVID-19 pandemic. The 45 papers presented in this volume were carefully reviewed and selected from 82 submissions. They were organized in topical sections as follows: medical applications; natural language processing; metaheuristics; image segmentation; databases; deep learning; explainable artificial intelligence; image processing; machine learning; and computer vision. .