Tag Archives: computer science

Extracting audio from video. Without a microphone.

We’ve all winced at those scenes in CSI:Nowheresville when somebody in a lab coat ‘enhances’ an image until you can see the reflection of the room in the pupil of somebody’s eye, or whatever.

This video is like that. Clearly implausible, most likely witchcraft.

Alternatively, a group of researchers at MIT really have found a way of extracting temporal information from CMOS sensor skew, sufficient to reconstruct audio up to around the 400Hz range from pictures alone.

Damned impressive, even if ‘sorcery’ is a more plausible algorithm.

Is Mirobot the droid we’ve been looking for?

In the previous post I wrote about the challenge of catching and holding peoples’ attention with electronics and programming activities – if you’ve seen DEMO: The Movie you’ll know I’m quite big on attention.

The Arduino microcontroller platform is a terrific tool, but it’s hard to present a project which is both immediately appealing and instructive. Projects tend to be fun but complex, or useful-but-dry tutorials. As with many fields of life, I suspect the answer is: robots.

Frikkin’ robots.

Lots of robots.

Continue reading Is Mirobot the droid we’ve been looking for?

Arduino: first steps

Pick a random stall at Maker Faire UK and there’s a fair chance it’ll have flashing LEDs. And where there’s a flashing LED, there’s usually a little blue circuitboard driving it. The blue board is the famous Arduino, a family of open-source microcontrollers designed to allow easy interaction between code you write and real-world sensors and actuators.

There’s a complex and ever-expanding ecosystem of Arduino-compatible boards and interface units, and to a novice it’s all a bit overwhelming. I am that novice. Indeed, the list of Arduino projects I’ve completed looks like this:

  1. [insert list of future projects here]

However, awareness of what’s possible expands one’s set of available tools, and Arduino feels like the sort of thing I might, at some point, find useful. So every now and then I tinker a little. My tentative, toe-in-the-water approach to Arduino goes like this:

Continue reading Arduino: first steps

Domino Computer

Stand-up mathematician Matt Parker and a team of volunteers build a functioning calculator out of dominoes, because… er… well, because they worked out how they could.

This has been festering in my pile of ‘unfinished hobby projects’ for longer than I’d care to admit, but just before I gadded off on holiday last month Matt prodded me with a very pointy stick. I’m delighted the film is finally seeing the light of day.

The film follows the domino computer build weekend at Manchester Science Festival with all its up and downs, and while we did try to explain how it works… well, turns out that’s quite tricky with hundreds of people milling around and thousands of dominos ready to fall over at a moment’s notice. So you might also want to check out this Numberphile film in which Matt explains the circuit with a little more care:

The team have also put together some worksheets, and can provide schools’ workshops (and dominoes!): think-maths.co.uk.

Elin also has a great bunch of stills of the weekend over on Flickr. Here’s one now. Note the breaks in the circuit during building, so an accidental fall doesn’t destroy the whole thing. There was a heap of work and expertise involved in building this thing, it really was a remarkable effort.

Set up