Slashdot Mirror

← Back to Stories (view on slashdot.org)

Implementating Transparent PNGs in IE7

Posted by timothy on from the hammers-and-tongs dept.

Brandon writes "Over at the official IE Blog, Sam Fortiner has posted some very detailed information regarding Alpha PNG Rendering in IE7. From the article: 'As the dev who implemented the support, I can state that it was neither a bug-fix nor did it require a re-write of the display engine. Instead, it ended up being somewhere in-between the two and required what I would call "feature work." Implementing transparency support for PNG images required a significant amount of modification to the image decoding and display pipeline in IE along with a significant amount of new functionality added to the PNG decoder.'"

4 of 97 comments (clear)

  1. libpng.... by __david__ · · Score: 4, Interesting

    So this implies they wrote their own PNG reading routines instead of using libpng?

    Is this some sort of NIH thing?

    libpng has a BSDish licence if I recall... So that can't be the issue...

    -David

    --
    There. Now go play some cool javascript games!
  2. Probably because IE displays images as they load.. by cwensley · · Score: 3, Interesting

    I'd imagine this would be why IE can show images as they download, instead of waiting for the whole thing to download like other browsers...

    I could be wrong..

  3. Re:You are by Anonymous Coward · · Score: 1, Interesting

    It uses libpng, just look at the shared libraries it is linked against.

  4. Re:Requires IE5, IE6 by Baron_Yam · · Score: 2, Interesting

    As an extremely crappy web site maintainer (I maintain a moderately unimportant site as the last and least significant of many duties)...

    The first thing I did on taking over the job was convince my boss that I needed to install Firefox and a Tidy-based HTML validator to ensure the site had been coded correctly... it wasn't. Several things didn't work properly, and a few things here and there just didn't load at all.

    Now that I have Firefox on my PC, I use it by default, and pop up IE to check the site for IE compatibility. Firefox is just a better freakin' product, especially with my four or five fave extensions.