Griffin Interactive

IE AlphaImageLoader filter and browser memory usage

The AlphaImageLoader filter does allow basic rendering of alpha transparent PNGs within the IE web browser, however heavy usage does come with a price in memory usage.

If your webpage does use images with transparency, then the performance difference will depend on how many of those images are present, what size they are, and how they are drawn". (Quoted from the IEBlog).

Take a look at challenger.se the site uses a number of Alpha transparent images, including the ability for the users to drag images around the page.

The author of the site has noticed a few issues when supported Internet Explorer.

I have noticed that IE doesn't free up the memory usage of a filter allocates, even though the element/object its attached to is "deleted"/removed dynamically. This should be taken care of. Otherwise, single-page-navigation-pages allocates very much memory fast.

A change of css-properties will cause IE to re-download any background-images it has attached to the element, event though the background property isn't affected. The "event" bubbles to parent elements as well, which causes additional download. I think this has to be fixed soon, obtain a high priority. (Quote from the Swedish author).

Filed under:

Web design