Abstract
A set of computer programs is described which has been developed for processing electron micrographs of biological structures. The programs provide facilities for efficient image storage, enhancement and display. Extensive programs are available for analysis of images of structures with translational, rotational and helical symmetry, and for performing 3-dimensional reconstruction. The considerations which went into the design of the system are listed. A description is provided of the means of control of the main program, which performs the majority of the image processing operations, and an example is given to illustrate its use. These programs are compared with other program systems also developed for micrograph image processing.