Simon Willison’s Weblog

25th January 2009 - Link Blog

OCR and Neural Nets in JavaScript. John dissects the brilliant Greasemonkey script that solves simple captchas using the canvas element and HTML5’s getImageData API.

Posted 25th January 2009 at 12 am

Recent articles

We're going to need default hard budget caps on pretty much everything - 3rd October 2026
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2026 in LLMs (so far) - 27th September 2026

This is a link post by Simon Willison, posted on 25th January 2009.

canvas 38 captchas 9 getimagedata 1 greasemonkey 54 javascript 765 john-resig 33 ocr 26

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