Introducing jQuery superpng plug-in

The superpng plug-in has been written to provide a flexible png alpha api to developers using jQuery and who need to support IE6. Other scripts didn’t provide the performance, features or flexibility that I required, as well as not using functionality available in jQuery which is fairy ubiquitous these days. The script uses either the AlphaImageLoader filter or the vml approach, depending on the type of tag and whether background-position is required.

For more information on alpha pngs and IE6, please see my previous post here.


Enable alpha images for all elements with a class of .png providing the relative path of the replacement transparent gif image:

$(document).ready(function() {
	$('.png').superpng({path: '../images/blank.gif'});

The full list of options are as follows:

  • path: define the location of the transparent .gif file used to replace the original png image
  • mode: filter/vml/auto (default) – describes the method used to enable png alpha.
    • filter:  The alpha loader fix is used, replacing the existing image with the blank image found in path.
    • vml: vml markup is placed inside the container. Requires a <div> or other block element.
    • auto:  A mode is chosen based on the tag type and background-position value.
  • cache: Determines if background images are cached. Default true.

Superpng is licenced under the the MIT, BSD, and GPL Licenses. Online examples are available here and the code is available on Github.

Please contact me with any feedback or any issues you may encounter.

Introducing jQuery superpng plug-in

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