Gulp image resize/optimize

gulpfile.js

// require gulp plugins 
var gulp = require('gulp');
var imageresize = require('gulp-image-resize');
var imagemin = require('gulp-imagemin');
var watermark = require("gulp-watermark");
var rename = require("gulp-rename");
var gulpif = require('gulp-if');
 

var paths = {
    folder: '',
    src: './batch/src/*', 
    dest: './batch/dist/'
}
 
// create an array of image groups (see comments above)
// specifying the folder name, the ouput dimensions and
// whether or not to crop the images
var images = [
	{ folder: 'lg', width: 1200, crop: false, watermark: false },
    { folder: 'weblg', width: 1200, crop: false, prefix: 'w', watermark: true },
    { folder: 'thumb', width: 275, height: 275, crop: false, prefix: 't', suffix: '_thumb', watermark: false},
    { folder: 'webthumb', width: 170, height: 170, crop: false, prefix: 'w', suffix: '_sm', watermark: false}
];
 
// images gulp task
gulp.task('default', function () {
 
    // loop through image groups		
    images.forEach(function(type){
    	
    	// build the resize object
        var resize_settings = {
            width: type.width,
            crop: type.crop,
            upscale : false
        }

        // only specify the height if it exists
        if (type.hasOwnProperty("height")) {
            resize_settings.height = type.height
        }

        var rename_settings = {}
        var dowatermark = type.watermark;


        if(type.hasOwnProperty("prefix")) {
    		rename_settings.prefix = type.prefix
    	}
 
        if(type.hasOwnProperty("suffix")) {
    		rename_settings.suffix = type.suffix
    	}

    	
        gulp
        
        // grab all images from the folder
        .src(paths.src)

        .pipe(gulpif(dowatermark, watermark({
	    	image: 'watermark.png'
	    })))

    
        // resize them according to the width/height settings
        .pipe(imageresize(resize_settings))
        
        // optimize the images
        .pipe(imagemin({
            progressive: true,
            // set this if you are using svg images
            svgoPlugins: [{removeViewBox: false}]
        }))

        .pipe(rename(rename_settings))
        
        // output each image to the dest path
        // maintaining the folder structure
        .pipe(gulp.dest(paths.dest+type.folder));
    });
});