The book "Invariant Object Recognition under Affine Transformations" by Guillermo Angel Pérez López addresses the fundamental aspects of object recognition in digital images, a central topic in computer vision. It explains how objects can be identified in images, even when they are distorted by various factors such as camera position or photometric effects. Special attention is given to invariance to viewpoints, which allows for the recognition of objects despite perspective changes. The method presented combines a novel technique for simulating viewpoints, known as ASIFT, with Fourier analysis of radial and circular projections (FORAPRO). The goal is to develop a robust algorithm that works reliably even with repetitive patterns and low contrast.