What is DIRSIG?

The name DIRSIG is an acronym for "Digital Imaging and Remote Sensing Image Generation". The first part of the formal name comes from the Digital Imaging and Remote Sensing (DIRS) Laboratory at the Rochester Institute of Technology (RIT) where the model was created.

The DIRSIG model is a complex synthetic image generation application which produces simulated imagery in the visible through thermal infrared regions. The model is designed to produce broad-band, multi-spectral and hyper-spectral imagery through the integration of a suite of first principles based radiation propagation sub models. These sub models are responsible for tasks ranging from the bi-directional reflectance distribution function (BRDF) predictions of a surface to the dynamic scanning geometry of a line scanning imaging instrument. In addition to sub models that have been specifically created for the DIRSIG model, several of these components (MODTRAN and FASCODE) are the modeling workhorses for the multi- and hyper-spectral community. All modeled components are combined using a spectral representation and integrated radiance images can be simultaneously produced for an arbitrary number of user defined bandpasses.