Sketchy

jarkman.co.uk

92 points·WestCoastJustin··8 comments

This is ultra-cool!

I wonder why they didn't take advantage of the fact that it could draw a huge amount of lines in a small amount of time and tweak their edge-detection algorithm to draw more lines.

Anyway, I'm sure there was very good reason why they haven't... likely the lines they can draw can't be very fine with the sort of marker they have to use.

The fact that he's just using canny suggests to me that it's just a simple hack he threw together. There are LOTS of other edge detection algorithms, but canny is pretty good and so easy to implement that it's the most generally used. It's not great at faces at a low resolution, but even just a little pre-processing can make the image better (as he demonstrates towards the bottom of the page).

Yes, 'simple hack' is definitely one reason. But there are a couple of others:

- The drawing is sent to the Arduino as a block, then drawn, so it has to fit in the Arduino's RAM. More complex drawings would require streaming the data during the drawing. That's totally possible, but it is more work.

- We quite liked the way these severely-simplified sketches came out. Because the edge-finding and vector-simplifying code is quite stupid, the best pictures tend to be the simplest ones, and doing more lines might well just make the picture more noisy.

Obligatory link:

http://www.chonday.com/Videos/the-writer-automaton

It's a doodling Autopen https://en.wikipedia.org/wiki/Autopen

Reminds me of the scene in iRobot where Sonny (the robot) draws the scene from his dream.

in any way related to piccolo (which had its v1 'release' today):

http://www.piccolo.cc/

Whoa, piccolo seems pretty cool. It would be nice if there were preassembled kits, not too familiar with laser-cutting and the like.

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