Command line version 集中線メーカ in Golang. (Please see http://hitode909.hatenablog.com/entry/2015/09/13/205925 if you don't know 集中線メーカ)
% go get github.com/syohex/speedline
% speedline -color=pink foo.png
% speedline -o=output.gif bar.gif
-oOutput file name-colorSpeed line color
