tufu is an image processing tool that likes gm,but it is lightweight without installing other software. U just run 'npm install tufu',then use it.
So far,it supports image format:jpg、bmp
npm install tufu
var tufu = require("tufu");
//cut image and save as path
tufu("./bg.jpg").cut(0,100,200,300).save("./bg2.jpg");
OR
//cut image,compress quality 60%,save as path
tufu("./bg.jpg").cut(0,100,200,300).compress(60).save("./bg2.jpg");
cut
resize
compress
scale
thumbnail(will be coming)
U can use on free with MIT License