PGMA_IO
ASCII Portable Gray Map (PGM) Files
Read and Write Utilities

PGMA_IO is a FORTRAN77 library which reads and writes files in the ASCII Portable Gray Map (PGM) 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.

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Languages:

PGMA_IO is available in a C version and a C++ version and a FORTRAN77 version and a FORTRAN90 version and a MATLAB version and a Python version.

Related Data and Programs:

PBMA_IO, a FORTRAN90 library which handles the ASCII Portable Bit Map (PBM) format.

PGMA, a data file directory which contains examples of ASCII Portable Gray Map (PGM) files.

PGMA_TO_PGMB, a C++ program which converts an ASCII Portable Gray Map (PGM) file to a binary PGM file.

PGMB_TO_PGMA, a C++ program which converts a binary Portable Gray Map (PGM) file to an ASCII PGM file.

PPMA_IO, a FORTRAN90 library which handles the ASCII Portable Pixel Map (PPM) format.

1. the NETPBM homepage.

Source Code:

• pgma_io.f90, the source code;
• pgma_io.sh, commands to compile the source code;

Examples and Tests:

• pgma_io_prb.f90, the calling program;
• pgma_io_prb.sh, commands to compile, link and run the calling program;
• pgma_io_prb_output.txt, the output file.
• pgma_io_prb_01.png, a PNG image of sample plot #1.
• pgma_io_prb_02.png, a PNG image of sample plot #2.
• pgma_io_prb_03.png, a PNG image of sample plot #3.

List of Routines:

• CH_CAP capitalizes a single character.
• GETINT reads an integer from a file.
• GET_UNIT returns a free FORTRAN unit number.
• PGMA_CHECK_DATA checks gray map data.
• PGMA_EXAMPLE sets up sample PGMA data.
• PGMA_READ_DATA reads the data in a PGMA file.
• PGMA_READ_HEADER reads the header of a PGMA file.
• PGMA_READ_TEST tests an ASCII portable gray map file.
• PGMA_WRITE writes an ASCII portable gray map file.
• PGMA_WRITE_DATA writes the data of a PGMA file.
• PGMA_WRITE_HEADER writes the header of a PGMA file.
• PGMA_WRITE_TEST tests the ASCII portable gray map write routines.
• S_EQI is a case insensitive comparison of two strings for equality.
• S_TO_I4 reads an integer value from a string.
• WORD_NEXT_RD "reads" words from a string, one at a time.

You can go up one level to the FORTRAN90 source codes.