Simon Willison’s Weblog

25th January 2009

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

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Two new Showboat tools: Chartroom and datasette-showboat - 17th February 2026
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The evolution of OpenAI's mission statement - 13th February 2026

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

canvas 38 captchas 8 getimagedata 1 greasemonkey 54 javascript 742 john-resig 33 ocr 25

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