Franz Enzenhofer built this cool feature that lets you draw a picture (or take a picture of yourself with your webcam) and then search Google Images using the search by image feature based on your drawing.
I decided to draw elmo, which can often turn bad because I am not a good artist. But here is a video demo of it in action:
To play with this tool yourself, go to Franz's web site.
He explained how it works:
- You draw something on an HTML5 canvas.
- Click on Search
- Image gets converted into a base64 encoded data uri
- Image data gets send to server (powered by Heroku)
- Image gets uploaded to Amazon S3
- The Amazon S3 Image URL gets communicated back to your browser.
- Browser gets redirected to Google Search by Image
Forum discussion at Google Blogoscoped Forums.