Reconstruction from projections

Reconstruction from projections refers to a computational process used in imaging techniques, such as computed tomography (CT), magnetic resonance imaging (MRI), and other forms of tomographic imaging. The idea is to create a three-dimensional representation or image of an object (or a specific volume of interest) based on two-dimensional projection data collected from various angles around the object. ### Key Concepts 1. **Projections**: These are 2D images or data slices obtained from different angles or orientations.