.CAL File

CALS Raster File Format is a bitmap format defined by the U.S. Department of Defense and intended for storing monochrome images.
There are two types of cal files:

• Type 1: Stores a single image per file and data is always compressed using CCITT Group 4.
   
• Type 2: Can store multiple images per file, the image data for each image can be subdivided into tiles, and each tile can be stored uncompressed, or compressed using CCITT Group 4.

MIME types:
image/x-cals

How to open:

These images can for example be opened and viewed using XnView.

How to convert:

XnView is able to transform *.cal files to other file formats.