node.js imagemagick resize

node-image-resize.js

(function() {

  'use strict';

  var async = require('async'),
    fs = require('fs'),
    im = require('imagemagick'),
    maxworkers = require('os').cpus().length,
    path = require('path');

  exports.resize = resize;

  function resize(params) {
    var queue = async.queue(resizeimg, maxworkers);

    fs.readdir(params.src, function(err, files) {
      files.forEach(function(file) {
        console.log('resize: ', file);
        queue.push({
          src: path.join(params.src, '/', file),
          dest: path.join(params.dest, '/', file),
          width: params.width,
          height: params.height
        });
      });
    });
  }

  function resizeimg(params, cb) {
    var imoptions = {
      srcPath: params.src,
      dstPath: params.dest
    };

    if (typeof params.width !== 'undefined') {
      imoptions.width = params.width;
    }
    if (typeof params.height !== 'undefined') {
      imoptions.height = params.height;
    }
    im.resize(imoptions, cb);
  }

}());

Example:

var imgResize = require('my_modules/image-resize');

imgResize.resize({
  src: 'img',
  dest: 'img/dist',
  width: 32
});