- Extension
- .cal
- .pgm
- Format
- Binary
- Binary
- Category
- Raster Image
- Raster Image
- Developer
- U.S. Department of Defense
- Jef Poskanzer
- Description
- The CALS raster file format, commonly known by the extension ".cal" or ".cals," is a bitmap file format designed primarily for the storage and interchange of digital images, especially in the field of computer-aided design (CAD) and engineering. Developed by the United States Department of Defense, it was intended to standardize the exchange of graphics data for electronic publishing of technical manuals. This format supports monochrome (1-bit) images and is distinguished by its efficient compression methods for reducing file sizes, facilitating easier storage and transmission. Despite its specific initial use case, the CALS raster format has found application in various industries for the archiving and sharing of high-resolution, scanned documents.
- A PGM file is a grayscale image file saved in the portable gray map (PGM) format and encoded with one or two bytes (8 or 16 bits) per pixel. It contains header information and a grid of numbers that represent different shades of gray from black (0) to white (up to 65,536). PGM files are typically stored in ASCII text format, but also have a binary representation.
- MIME Type
- image/cals
- image/x-portable-graymap
