Glue is a simple command line tool to generate sprites:

$ glue source output

• The latest documentation is available at: http://glue.readthedocs.org
• Installation instructions: http://glue.readthedocs.org/en/latest/installation.html
• Glue-users mailing list: https://groups.google.com/forum/#!forum/glue-users

• Automatic Sprite (Image + Metadata) creation including:
  • css (less, scss)
  • cocos2d
  • json (array, hash)
  • CAAT
• Automatic multi-dpi retina sprite creation.
• Support for multi-sprite projects.
• Create sprites from multiple folders (recursively).
• Multiple algorithms available.
• Automatic crop of unnecessary transparent borders around source images.
• Configurable paddings and margin per image, sprite or project.
• Watch option to keep glue running watching for file changes.
• Project-, Sprite- and Image-level configuration via static config files.
• Customizable output using jinja templates.
• CSS: Optional .less/.scss output format.
• CSS: Configurable cache busting for sprite images.
• CSS: Customizable class names.
• Python 2.6, 2.7 and 3.3+ supported.
• Really well tested.

Using the gorgeous famfamfam icons (4.2Mb) you will get the following icons.png (401Kb).

And also an icons.css with all the necessary CSS classes for this sprite:

.sprite-icons-zoom_out{ background:url('icons.png'); top:0; left:0; no-repeat;}
.sprite-icons-zoom_in{ background:url('icons.png'); top:0; left:-16; no-repeat;}
.sprite-icons-zoom{ background:url('icons.png'); top:-16; left:0; no-repeat;}
.sprite-icons-xhtml_valid{ background:url('icons.png'); top:-16; left:-16; no-repeat;}
...

Do you want to know more? Visit the quickstart guide: http://glue.readthedocs.org/en/latest/quickstart.html

• Fork the repository on GitHub to start making your changes to the master branch (or branch off of it).
• Write a test which shows that the bug was fixed or that the feature works as expected.
  • Use python setup.py test
• Send a pull request and bug the maintainer until it gets merged and published. :) Make sure to add yourself to AUTHORS.

We are creating a list of companies using glue in production. If your company use glue, please send me an email or send me a message to @jorgebastida . I would really appreciate it.

There are several features that glue users would love to have... but they require a substancial amount of work and dedication, so we are looking for feature-sponsors! If you want to lead the development/testing of any of the following features, please contact Jorge Bastida.

Here you have some examples:

• Windows support (I'm not a Windows user, glue needs somebody who care about how glue works on Windows and write down some installation instructions).
• Cocos2d Format (Already exists, but we need somebody to give it some love).
• New Formats (After 0.9, glue is ready to accept new output formats - If you want to create a new format, contact me).
• Binary packaging for OSX and Windows (For some users it would be really cool if they were able to download an already packaged binary version).