A simple utility to convert JPEG to PGM, souce code is based on John Gauch's Work.
Hopefully please build under Linux using gcc(cygwin will work too, if you prefer, you can try mingw also:-)).
Please see the Makefile.
Please see the Makefile.
Please see the Makefile.
jpg2pgm file.jpeg file.pgm,e.g,jpg2pgm test.jpeg test.pgm