[standards, photogrammetry]
An abbreviation of National Imagery Interpretability Scale. In imagery, it is a subjective scale of image quality that defines levels of interpretability in terms of features that can be effectively resolved and identified. The NIIRS consists of 10 levels, from 0 (lowest quality) to 9 (highest quality), based on ground sample distance (GSD), clarity, and the multispectral characteristics of the sensor system.