This book chapter provides an extensive overview of the rasterdiv package which provides a comprehensive suite of functions designed to calculate diversity indices from numerical matrices, including those derived from optical remote sensing imagery. It facilitates a deeper analysis of spatial heterogeneity and ecosystem complexity by translating pixel values into ecological indicators. This package serves as a valuable tool for researchers and practitioners in the fields of landscape ecology, biodiversity monitoring, and environmental management, allowing for an enhanced understanding of landscape patterns and their ecological implications through advanced quantitative measures.