Simon Willison’s Weblog

Animating a commit based Sudoku game using Puppeteer (via) This is really clever. There’s a GitHub repo that tracks progress in a game of Sudoku: Anish Karandikar wrote code which iterates through the game board state commit by commit, uses that state to generate an HTML table, passes that table to Puppeteer using a data: URI, renders a PNG of each stage and then concatenates those PNGs together into an animated GIF using the gifencoder Node.js library.

# 9th October 2020, 10:28 pm / puppeteer, datauri, gifs

Evolution of <img>: Gif without the GIF (via) Safari Technology Preview lets you use <img src="movie.mp4">, for high quality animated gifs in 1/14th of the file size.

# 4th December 2017, 7:28 pm / gifs, safari, video

“I made the first animated under construction icon”. twoleftfeet on MetaFilter describes how he created the first ever Under Construction animation in 1995, after discovering his server-push animations could be replaced by the exciting new animated GIF.

# 15th October 2009, 2:11 pm / metafilter, underconstruction, animation, gifs, internet-history, history

Evil GIFs: Partial Same Origin Bypass with Hybrid Files. First there were PNGs that had crossdomain.xml files embedded in them, now there are GIFs that contain Java applets (as JAR files). At this point I’d say don’t even bother trying to validate uploaded files, just make sure they’re served off an entirely different domain instead where XSS doesn’t matter.

# 1st July 2008, 8:58 am / xss, security, validation, uploads, pngs, crossdomainxml, gifs, javaapplets, applets