Convert a PCX file to a PPM image. More information: https://netpbm.sourceforge.net/doc/pcxtoppm.html.
pcxtoppm path/to/file.pcx > path/to/file.ppm
pcxtoppm -stdpalette path/to/file.pcx > path/to/file.ppm
stdout
:pcxtoppm -verbose path/to/file.pcx > path/to/file.ppm