thumbnail

Small utility to easily and efficiently create thumbnails using GraphicsMagick.

Usage examples

Get a 100x100 thumbnail of /path/to/originals/picture.jpg and store it in /path/to/thumbnails

var Thumbnail = require('thumbnail');
var thumbnail = new Thumbnail('/path/to/originals', '/path/to/thumbnails');

thumbnail.ensureThumbnail('picture.jpg', 100, 100, function (err, filename) {
  // "filename" is the name of the thumb in '/path/to/thumbnails'
});

Get a thumbnail of 100 pixels wide, height auto and store it in /path/to/thumbnails

var Thumbnail = require('thumbnail');
var thumbnail = new Thumbnail('/path/to/originals', '/path/to/thumbnails');

thumbnail.ensureThumbnail('picture.jpg', 100, null, function (err, filename) {
  // "filename" is the name of the thumb in '/path/to/thumbnails'
});

Get a thumbnail of 100 pixels high, width auto and store it in /path/to/thumbnails

var Thumbnail = require('thumbnail');
var thumbnail = new Thumbnail('/path/to/originals', '/path/to/thumbnails');

thumbnail.ensureThumbnail('picture.jpg', null, 100, function (err, filename) {
  // "filename" is the name of the thumb in '/path/to/thumbnails'
});

Installation

$ npm install thumbnail

API

Thumbnail(rootOriginals, rootThumbnails, [supportedImageTypes])

• rootOriginals String
• rootThumbnails String
• supportedImageTypes Array, default = [ 'png', 'jpg', 'jpeg', 'gif' ]

Construct a thumbnail object that operates on the provided paths. rootOriginals is the path where the original files can be found and rootThumbnails is the path where thumbnails can be found and created.

supportedImageTypes is an optional array of supported images. Make sure your GraphicsMagick installation supports these types.

thumbnail.ensureThumbnail(filename, width, height, cb)

• filename String
• width Number
• height Number
• cb Function

Create a thumbnail of filename with the requested width and height. filename should exist in the rootOriginals path provided to the constructor. If a thumbnail with these dimensions already exists, no new file is created and the filename of the existing thumbnail is returned via the callback.

width and height should be the requested thumbnail size in pixels. When only width is provided, the height of the thumbnail will be aspect ratio. When only height is provided, the width of the thumbnail will be aspect ratio.

cb is called with Error or null as the first parameter. The string of the thumbnails filename as the second parameter. And as the third parameter a boolean if the thumb has just been created or if it already existed (in that case it will be false).

thumbnail.rootOriginals

• String

path to original pictures as given to the constructor

thumbnail.rootThumbnails

• String

path to thumbnails as given to the constructor

thumbnail.supportedImageTypes

• Array

supported image types as given to the constructor

Requirements

GraphicksMagick must be installed on your system and the gm command should be available in the node environment.

License

MIT, see LICENSE