basic:
rsvg -w 2160 -h 1440 icon-recert.svg icon-recert.png
$ rsvg
Usage: rsvg [OPTIONS...] file.svg file.png
-d, --dpi-x=<float> pixels per inch
-p, --dpi-y=<float> pixels per inch
-x, --x-zoom=<float> x zoom factor
-y, --y-zoom=<float> y zoom factor
-w, --width=<int> width
-h, --height=<int> height
-q, --quality=<int> JPEG quality
-f, --format=[png, jpeg] save format
-v, --version show version information
http://superuser.com/questions/516095/bake-an-svg-image-into-a-png-at-a-given-resolution