Convert an AutoCAD slide file to a PPM image. More information: https://netpbm.sourceforge.net/doc/sldtoppm.html.
sldtoppm {{path/to/input.sld}} > {{path/to/output.ppm}}
sldtoppm {{[-a|-adjust]}} {{path/to/input.sld}} > {{path/to/output.ppm}}