Convert a Utah Raster Tools RLE image file to a PNM file. More information: https://netpbm.sourceforge.net/doc/rletopnm.html.
rletopnm {{path/to/input.rle}} > {{path/to/output.pnm}}
rletopnm {{[--a|--alphaout]}} {{path/to/alpha_file.pgm}} {{path/to/input.rle}} > {{path/to/output.pnm}}
stdout:rletopnm {{[--verb|--verbose]}} {{path/to/input.rle}} > {{path/to/output.pnm}}