Some Properties of Image-Processing Operations on Projection Sets Obtained from Digital Pictures
Shliferstein, Chien · IEEE Transactions on Computers · 1977
A projection of a digital picture (image) may be defined as an ordered set of values, each of which is the sum of the gray levels along a given path drawn through the picture. A projection set is at ordered set of projections of the picture. Given a projection set, reconstruction is achieved by operating on the projection set to produce either the original picture or an approximation to it.