.
    +--LPM Sample Program:0README
    +--Makefile
    +--grid-lp.gif
    +--grid-lp.ppm
    +--grid-lpinv.gif
    +--grid-lpinv.ppm
    +--grid.gif
    +--grid.obj
    +--grid.ppm
    +--Log Polar Mapping.:lpscl.c
    +--Invert Log Polar Mapping.:lpsclinv.c
    +--Open PPM file and get size of width and height.:ppmutils.c
    +--ppmutils.h