JEDMICS C4 is a bi-level raster image file format. It is also known by other names, such as EDMICS C4. It was incorporated into CALS raster as CALS Raster Type 4.
The name comes from an entity named JEDMICS (Joint Engineering Data Management Information and Control System), which is related in some way to the U.S. Department of Defense.
It was designed by Image Machines Corporation. See also TG4 (Image Machines).
Files have a 128-byte header, followed by a tile index, followed by the pixel data in the form of a set of 512×512-pixel tiles. Each tile is compressed with CCITT Group 4, or is uncompressed.
Files begin with (hex) bytes
80 00 00 00. The byte at offset 36 is
06. See the "Header Error Conditions" section of the specification for more constraints.