The FITS image extension
J. D. Ponz, R. W. Thompson, J. R. Munoz · Astronomy & Astrophysics Supplement Series · 1994
The Flexible Image Transport System (FITS) image extension provides a convenient means of storing two or more related but not necessarily identical multidimensional arrays in a single file. If conforms to the guidelines and rules for generalized FITS extensions and is structured in a manner identical to that of a primary header and data unit; thereby making if simple to interpret and compatible with existing FITS readers. The structure of the image extension and its potential uses are discussed