I’ve been talking to Pierre Raufast for a little while now about his efforts to get OpenCV ported smoothly to the Raspberry Pi camera board (which is available from the usual suspects: head to the links under “Buy a Pi” at the top right). OpenCV is an open-source library for real-time image processing, and is used in applications like gesture mapping, motion tracking – and facial recognition.
You might recognise Pierre’s name from a project we featured here back in April. The Magic Mirror recognises people looking into it, and talks to them accordingly. Back then he was using a webcam; now he’s got his hands on a camera board. The Raspberry Pi camera board is a better fit for the device, with a much higher framerate and better resolution.
In most webcams, OpenCV works natively. But because the Pi camera board isn’t a USB device, some work needed to be done to get it up and running. Pierre has done a bang-up job, and has made a seven-part tutorial available to get you up to speed. When you’re done, you’ll be able to see results like this:
Thanks Pierre – we can’t wait to see what you do next!
Some housekeeping first. As you can see, I’m upright and typing again. Turned out that I had a really unusually nasty dose of ‘flu. It started as what I thought was a bad cold, but kept getting worse, until it got to a point when I couldn’t get my head off the pillow and thought I was dying. Then it got even worse, and I started wishing I was dying.
I’m much improved, but still a little wobbly. Doing anything (walking up the stairs, watering the garden) still leaves me feeling like I’ve just run a marathon, so I’ll be taking things slowly for a few days. On that note, if you want to email me this week, it’d be great if you could wait until next week if your mail isn’t blindingly urgent: I’ve got a backlog of hundreds and hundreds of mails to work through at the moment because I haven’t been able to check them while I’ve been off, and it’s going to take me a while to get through them all.
I’ll be working on a post about what we got up to with the amazing Pi community in Japan for later in the week, but for now, here’s something topical.
Our good friends at Adafruit have been working on a Tor proxy box based around a Pi, which directs your internet traffic through the Tor routing service. Every network packet you send is encrypted and decrypted multiple times, and each time this happens the packet is sent through a number of relays (like onion skins: Tor stands for The Onion Router), picked at random from the thousands that make up the Tor network, before reaching its intended destination. This makes it very hard for anyone to analyse your data to find out who you are, or where you are.
Tor routing is for anyone interested in confidentiality, internet freedom and privacy. It’s of enormous use for those who need to work on confidential business, or for those in places where internet traffic is monitored by governments or other bodies. It’s used to search for forbidden material like birth control, dissenting political voices or religious debate in places where a country is behind a firewall and traffic is strictly controlled (there are many users in mainland China); in the western world it’s used by many to protect personal data from marketers, and by those who worry their data is being snooped on. Activists and whistleblowers, for whom anonymity is important, use Tor. A healthy paranoia about your internet traffic is a good thing: just because you’ve got nothing to hide doesn’t mean that you’ve got nothing to fear. I would hate to be labelled a terrorist just because I express an interest in pressure cookers and book a lot of aeroplane tickets.
You can, of course, run a Tor proxy on any machine, but the particularly nice thing about Adafruit’s Onion Pi is its portability. This means that you’re not restricted to using it in one place; you can set it up in front of the router (it behaves as a WiFi hotspot) in the office you’re working from, in your hotel room or at your Mum’s house, connect to it from your phone or computer, and your IP address will be anonymised.
Be aware that using Tor will slow your browsing down (the packets of data are travelling by a longer and less direct route than you’re used to), and that it’s not a total guarantee of anonymity.
Update 12 June: Liz continues to recover, but I’m still not letting her near the blog until she stops coughing like that.
Liz has spent most of this week suffering from an affliction picked up in Tokyo. We’re assuming this is flu, as even the worst sake hangover doesn’t usually last this long. I’ve sent her to bed to rest up; normal service will be resumed when she’s feeling better, hopefully early next week.
Liz: This post comes from Heather and Trevor Grant, who work with a student-led charity called The Best of Both, based at the British School of Brussels. Thanks both! For the past five years The Best of Both initiative has worked with state-sector rural schools around Bolgatanga in the Upper East of Ghana to help improve access to water, food – through school gardens – and educational resources (books and access to ICT). Last year, computer labs based on NComputing… More
Cristos Vasilas from Dash One, a lover of astronomy and electronics, has been trying out the Raspberry Pi camera board as an astrophotography tool. He’s captured some amazingly sharp, short video of the moon, and of Saturn, rings clearly visible, swinging across the sky. Cristos used foam packing material to attach the camera board to the eyepiece of his telescope, and mounted the Pi on the barrel of the telescope with velcro. He says: “A dedicated Celestron 5M pixel imager costs… More
If you’re a beginner with a Raspberry Pi, things just got a whole lot easier. We started this project with the premise that throwing people in at the deep end and making them jump hurdles, to mix my sporting metaphors, is a good way to get them to learn stuff. It is: but it can also put some people off, sometimes terminally. And we don’t want people to put their Raspberry Pi down in horror after five minutes. So with… More
Team MagPi have wiped their bleary eyes after celebrating their first anniversary issue, and have come up with a magazine for June that will have you playing the Archimedes version of Elite on your Pi, writing racing games in Scratch, and making music with Schism. You’ll learn how to solder up a LED matrix, find out about the growing number of expansion boards available for your Pi – and this month, there’s a very special cover feature. You might remember… More
Update: copied Alex’s summary of the changes to Raspbian from the comments into the post. We’ve just posted updated Raspbian, Debian and Arch Linux images on the downloads page, all of which include our most recent firmware and kernel. Raspbian has the following significant changes: Updated Scratch image (significant performance improvements). Updated armv6-optimised Pixman library. Updated armv6-optimised memxxx() functions. Updated raspi-config with new layout, and new functionality (setting hostname and enabling camera support). Native mmap support in the bcm2835 ALSA… More
We’ve been talking a bit about London Zoo’s efforts with the camera board to set affordable camera traps in Kenya, looking not only for wild animals, but also for poachers. This is incredibly important work; rhinos, elephants and other terribly endangered animals are targeted for their body parts, which fetch large sums in some markets. This project is one of several up for a £500,000 grant from Google, but to get that grant, they need your help: please go and… More
SailBot 2013 International Robotic Sailing Regatta is a robotic sailing competition in which the goal is to create an unmanned sailboat that navigates through a variety of challenges with limited, if any, human control. We met the Aberystwyth Sailbot team at the recent Cambridge Raspberry Jam. Their Sailbot uses a Raspberry Pi to make sure its tiny little crew make their way safely back home and we liked it so much that we are proud to be sponsoring them. Daniel… More
A thread about Raspberry Pi ended up on the front page of Reddit today, and it’s a doozy. There are thousands of people taking part, and some Pi projects mentioned that we’d never even imagined people taking on. Some of them made our little hearts swell with pride. Teaching machines for schools in Ecuador, prosthetic knees in the USA, musical instruments controlled by eye movements for disabled people, solar flare detection, wood engraving, pocket-money analyser – there’s something here for… More
There’s a question we’ve been asked very frequently about the camera board. A number of you want to use it for night-time photography, and ask if we can remove the IR filter. Notably, London Zoo are planning to deploy the camera board and Pi in a number of camera traps in Africa, where they’ll be looking for nocturnal animals and for poachers. The problem is, we source the sensor/lens package as a sealed unit from Sunny, so we don’t have… More
New in the Swag Shop: big vinyl stickers, just the right size for hiding any logos you don’t like on the front of your laptop, and little vinyl stickers, just the right size to cover up the logo on the Windows key on your keyboard. These things are tough, and have what I understand is called “high-traffic glue” on them to make them stand up to your typing. There are some other new goodies available this week too: a logo… More
Update: Daniel’s blog post here provides some more info, including how to install the technology preview on Raspbian today. And Pekka’s blog post here has some very detailed technical information on the implementation of the Weston backend. If you’re familiar with the Raspberry Pi desktop experience, you’ll have noticed that windows on the desktop can be a bit slower to move around than you’re used to on your PC or laptop. This is because X, the windowing software (or composition… More
efort, 1 minute ago:
General discussion • Re: Why were so many pins dedicated to power…
()blivion wrote:OP's complaints seem more political than technical, so this is mostly irrelevant to the topic. But if one was worrying about this because they wish they had more usable pins they could work with, the two flex cable connectors…
naftaism, 3 minutes ago:
Italiano • Re: internet connection
Conosco la via "android" per eseguire un thetering usb, ma iphone... purtroppo non saprei da dove iniziare, ma sgooglando qua e la si trovan un pò di info: http://lmgtfy.com/?q=thetering+usb+iphone+linux
spiffly, 6 minutes ago:
Interfacing (DSI, CSI, I2C, etc.) • Re: 0-10v PWM possible?
PiGraham wrote:spiffly wrote:mahjongg wrote:Yes, indeed, if you have a 10V source then using a simple level shifter would be simple.The level shifter can consist of a NPN transistor that shorts a 4K7 pullup-to-10V to GND. You control it with the…
tekgiant, 9 minutes ago:
Troubleshooting • Re: First boot, Nothing on Screen
Editing the config.txt file was all I needed to do. I opened the config.txt file using the vi text editor.I uncommented the:Code: hdmi_force_hotplug=1 and addedCode: hdmi_edid_file=1 After that I saved the file, quit the editor and rebooted the Pi and…