pgma_io, a Fortran90 code which reads and writes files in the ASCII PGM (Portable Gray Map) format for 2D grayscale graphics information.
There are many graphics programs, such as XV and GIMP, that can display images in this format, or translate them to other formats such as BMP, GIF, JPEG, MacPaint, X Window, and so on.
The information on this web page is distributed under the MIT license.
pgma_io is available in a C version and a C++ version and a Fortran90 version and a MATLAB version and an Octave version and a Python version.
pbma_io, a Fortran90 code which handles the ASCII Portable Bit Map format.
ppma_io, a Fortran90 code which handles the ASCII Portable Pixel Map format.