Innnards: MNG is dead, long live APNG

As the author of the WWW FAQ, I regularly answer questions about the workings of the Web. If a question is frequently asked, I simply add an article to the FAQ. But sometimes a question is more detailed, more in-depth— not really a FAQ, but still of interest to others. You'll find those questions, with my answers, here in Innards along with commentary on other web-technology-related topics.


I am partly responsible for the PNG image format. I got the ball rolling, played benevolent dictator and edited the first nine drafts. PNG is moderately successful, but it never did replace GIF. That's mainly because Netscape sprang animated GIF on the world when the PNG specification was nearly final, without saying a word or once suggesting that we include animation.

When animated GIF appeared, I lobbied the PNG group for simple, GIF-style animation support in PNG, which would have given the world a lossless true-color animation format with an alpha channel... even if it wasn't any more sophisticated than GIF from an animation point of view. I lost out to those who made eloquent arguments for a more complete animation format.1 MNG, the all-singing, all-dancing, all-merciless animation format, took a long time to standardize and was rejected by both major web browser vendors, who perceived it as too complex and requiring too much code to implement.

Very recently, two young turks decided to invent a simple new animated-PNG format, tossed something together, and came up with a patch for the Mozilla browser. It is completely obnoxious from a standpoint of harmony with the elegant language of the PNG specification2 and completely compatible from a practical standpoint with existing software in much the way that most existing programs tolerated animated GIFs well even if they didn't understand animation. It is kicking up a shitstorm on the long-dormant PNG mailing list. The old-timers and the young turks are trying to hash out an agreement. I agree for the most part with the young turks and their design choices.

I could not be more pleased with this development.

1. So much for dictatorship. At least I was benevolent.

2. "We the people, in order to draw a more perfect bitmap..."