Sonar Software Detects Laptop User Presence

Steve Tarzia writes "A research group at Northwestern University and University of Michigan has released open-source display power-management software that uses a new user presence detection technique. The goal is to shut off the display immediately when the user leaves the computer rather than using slow and error-prone mouse/keyboard activity timeouts. Surprisingly, the mic and speakers of many laptop computers are sensitive to ultrasonic frequencies. Those frequencies can be used to silently probe the laptop's physical environment. This software is based on research published at the UbiComp2009 conference. A Windows binary and source code for Windows and Linux are available for download."

Comments

Takes Care of one of my pet peeves

[gpronger]

Don't know if I type slow, think slow, or both, but one of my pet annoyances is when the screen saver kicks-in as I'm staring at the screen in thought (sure I know how to set it, but I am not always in front of my own PC, and oft away and then back a lot through the day).

If this will simply tell the OS, hold on, he's sitting there doing something, I'd find it a pretty neat idea.

Greg

Re:Takes Care of one of my pet peeves

[schon]

Something like this has been available for KDE for ages, only it uses Bluetooth.

You tell it to listen for your phone - when you leave your desk (presumably with the phone in your pocket/holster/etc.) the screen lock kicks in.

Re:Takes Care of one of my pet peeves

[dlgeek]

Yes, I know this was intended as a humorous remark, and yes I get the joke (please refrain from any "woosh" comments), but in all seriousness, this actually is an issue for X11 based systems.

Due to a poor design choice in X11, applications can see when the mouse moves but can not see button press events in other applications. One result of this is that screensavers can't detect a mouse wheel. Thus, if you're scrolling through a long article, the mouse wheel events aren't seen, the screensaver considers you idle, and will lock the screen even as you're scrolling.

It's actually quite annoying...

I wonder how...

[Whorhay]

I wonder how fine of a resolution is possible with a setup like this with generic microphones and speakers. Maybe it would be possible to use this as a biometric lock on a computer system. It could function as a facial recognition check using the ultrasound picture or series of pictures of your face. Lighting wouldn't affect it and someone couldn't simply use a picture of you to try and fool the camera. Even a bust of your face wouldn't work the same unless it accurately simulated your bone structure and flesh.

Re:I wonder how...

[maxfresh]

I agree that a webcam would do a far better job than speakers and mic, but they couldn't use body heat to do it.

Although a ccd or cmos sensor in a webcam, or most any other digicam, is sensitive to IR as you mention, it is not sensitive to the thermal IR of body heat. Most digital cams are capable of IR sensitivity out to about 1um, if you remove their IR-cut filter. The human body with a skin surface temp of about 305 Kelvin emits most of its IR energy at a wavelength about 10x longer than this, or 9.5um.

Re:I wonder how...

[Z34107]

Asus ships the software you're describing with laptops they sell; it came on mine. It takes a bunch of snapshots of your face through the webcam (you're supposed to rotate your head) and then if it sees your face at the login screen, it logs you in.

They call it "SmartLogon."

Re:Activity

[jhfry]

Your privacy concerns are valid... however think of the applications for this tech.

Your instant messenger will know when your available or not.
Your phone system could direct your calls to you mobile if your away from the desk.

Proximity may also be important break for the future of voice activated computing. If the computer knows your there, it can listen, and when you leave it ignores any sounds.

I think there will be applications for this tech far beyond pc's, especially once it becomes common.

I'm one of those people that hears CRT Monitors

[ArbitraryDescriptor]

And dimmer switches, cordless drill battery charges, and even a really annoying slice of whatever frequency god damn bats chatter at. In short, my super power is above average HF hearing. Hooray for me...

Now, I like this idea, it's neat, I just really hope it operates well over 18khz so my head does not explode all Scanners style when I walk into a room full of laptops.

Re:I'm one of those people that hears CRT Monitors

[Khith]

I can hear at least up to 20kHz (as high as my speakers' frequency response goes, so I can't test any higher) and it really IS a pain sometimes. The most useful thing I've been able to do is remind them that they left the TV on in the other room. "But I turned off the power and the screen is black.." No, you turned off the power to the cable box which cut out the image and sound on the TV, but I can still hear the flyback transformer. Of course this doesn't work on LCD TVs, though they sometimes just hum or buzz quietly anyway.

I'm 31 years old. I thought that people around my age weren't supposed to hear such things? Is it all related to one's environment? I don't listen to loud music, avoid loud places, etc, but I still thought that hearing was supposed to diminish.

Re:Activity

[Red Flayer]

Your privacy concerns are valid... however think of the applications for this tech.

/+5 Hat of Greed equipped.

Oooh, I'm drooling! Let's see:

$APP detects two people within viewing distance of your monitor. [click here] to upgrade to the appropriate license.

/+5 Hat of Greed unequipped.
/+5 Hat of Stealth equipped.

Oooh, I'm drooling for different reasons. Let's see:

$APP detects additional person approaching monitor. Autominimize firefox://ridiculous.pornsite.com; automaximize firefox://romanticweekendgetawayswiththewife.toshowherhowmuchyouloveher.com.

Whew, that was a close one.

Why ?

[smoker2]

What's wrong with a keyboard shortcut key or assigning a function key ? It's a laptop, you probably don't just walk away frequently and leave it unattended. Not anywhere I know anyway.

I'm just a slave to the machine...

[Kazoo the Clown]

Just tell me where I put the postit note or soda bottle to fake it out so it thinks I'm there all the time...

Re:How about a license ; how about saying Linux(tm

[olau]

You got that backwards. What they should do is deleting the remark about Windows. Anyone succumbing to the (tm) crap should have their head examined. Every time somebody writes "registered trademark", god kills a kitten. It's true. Between us, we just killed two. No, I'm not going to write it again.

Now someone is going to say legal blahblah necessary blahblah. But there is something wrong if fear of a big corporation is making you write that kind of kitten-lethal nonsense every time you mention a product made by that corporation.

So the device in Dark Knight

[geekoid]

Could be built. Interesting.

Re:Headphones

[CAIMLAS]

That.

Personally, I went back to just using ALSA + internal alsa mixer. That kinda sucked (couldn't get it to consistently mix, particularly with Flash, and it would frequently result in poor quality crap while doing so), so...

I went back to what I was doing a decade ago: use ESD (wherever possible). I suppose I could use JACK or something else, but it does a good enough job and I'm not continually irritated with alsa dying outright due to different things vying for -whatever-.