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BoB-
April 12th, 2002, 02:47 AM
Communication is probably the most important thing in our hobby, but often on cold nights when the air is thinner, any communication at all may be heard, betraying your position. This new technology recognizes words being spoken by detecting muscle movement around the mouth. Not a single word need be spoken it can be used with a speech syntheziser to send the message like a normal telephone, or it can send the message as written text, completly removing the need for sound.

"Lip-reading cellphone silences loudmouths

19:00 03 April 02

Exclusive from New Scientist Print Edition

The world's first lip-reading mobile is being developed by researchers at Japanese cellphone maker NTT DoCoMo.

Although still some way off, the phone should put an end to users having to shout down their handsets, even in noisy environments. All they have to do is mouth their words silently, and the phone will convert them to speech or text.

DoCoMo's early prototype works out which words are being said by using a contact sensor near the phone's mouthpiece to detect tiny electrical signals sent by muscles around the user's mouth. The signals are then converted into spoken words by a speech synthesiser, or into text for a text message or email.

DoCoMo reckons that avoiding the need to tap out emails on a tiny keypad could be a significant bonus when future 3G networks arrive.

Cellphone etiquette

Engineers are still developing the lip-reading software for the project. They say a test model can now recognise vowels with what they call an acceptable error rate, and are now working on the tougher task of recognising consonants. Lip-reading accuracy, they say, could also be boosted using the tiny cameras that will be common on 3G phones.

The spur to developing such a phone, says DoCoMo, was ridding public places of noise. In Japan, mobiles are already banned on some public transport networks, and in many other places etiquette requires that people using a phone have to hold a hand discreetly over their mouth.

The technology is also expected to help people who have permanently lost their voice, says DoCoMo, which plans to make it available in about five years' time."

From;
<a href="http://www.newscientist.com/news/news.jsp?id=ns99992122" target="_blank">http://www.newscientist.com/news/news.jsp?id=ns99992122</a>

nbk2000
April 12th, 2002, 03:41 AM
Interesting.

Especially about the part of a lip reading camera. Attach a telephoto lens and things start getting REALLY interesting. <img border="0" title="" alt="[Wink]" src="wink.gif" />

I've read of a project for SOF that uses an IR laser with a voice modulator/demodulator for uninterceptable line-of-sight communication. The device is built into NVD googles. You simply look at the person you want to talk to, push a button, and start yapping.

The receiving part is omni-directional.

There's no reason you couldn't build the same thing.

I'm thinking a hand-held mouthpiece (like a pilots oxygen mask) you'd speak into that'd muffle your talking. An IR diode is built into the front, and an earpiece attached to a reciever collar studded with IR transistors would permit 360 degree reception.

Just hold the mask over your mouth while looking at the intended receipient, and speak.

Hand signals are useful if you can be seen. Army manuals have a bunch that could be used as is or modified.

There's also a keying device that has two sliding disk pads. The combination and direction in which you slide the pads determines the letter/number being keyed. It's not the fastest thing in the world, but you can do it wearing thick gloves and is silent.

BoB-
April 13th, 2002, 01:43 AM
I thought about palmpilot technology, there are programs that let you just write on the screen in cursive or print, and it will convert it to text.

There are also cellphones that have text messaging built right in specifically for silent communication in theatres and public places. Unfortunatly it only lets you send a few words, and most people who use them type in symbol (the most annoying type on earth).

zeocrash
November 5th, 2002, 04:51 PM
the problem with a lip reading camera would be misinterpretation. this is because too many words have similar lip movement patterns

kingspaz
November 5th, 2002, 06:23 PM
moving to tools and techniques...

Anthony
November 5th, 2002, 06:27 PM
You don't need to catch every syllable of every word in a speach passage to be able to get the meaning of it. English is a rather high redundancy language, and deaf people manage to do quite well with lip reading.

AfterRain
November 5th, 2002, 09:19 PM
Nbk - </font><blockquote><font size="1" face="Verdana, Arial, Helvetica">quote:</font><hr /><font size="2" face="Verdana, Arial, Helvetica"> I'm thinking a hand-held mouthpiece (like a pilots oxygen mask) you'd speak into that'd muffle your talking. An IR diode is built into the front, and an earpiece attached to a reciever collar studded with IR transistors would permit 360 degree reception </font><hr /></blockquote><font size="2" face="Verdana, Arial, Helvetica">But would'nt that trap the sound waves ? Now if some one was to use a laser mic, I think they'd be able to hear your side of the converstaion

BoB- The cell phone is good, but there are ways of intercepting the information . DDI, Digital Data Intercation, Which would be good for low tech op's. But for high scale shit, i'd not trust it, Unless there was a 3rd party to encrypt the data.

Also for both of the above,If you could use a custom made trunking system that would make it all more secure, Like use Low frequency's below 30mzh,(Some of the Ones under 30 are used in the cb) , then make it bounce its way to the gig frequency . &lt;-- Just a thought, alot harder then said .

<small>[ November 05, 2002, 09:08 PM: Message edited by: AfterRain ]</small>

nbk2000
November 6th, 2002, 04:18 AM
:confused:

What are you rambling on about?

I assume you mean the enemy having an IR demodulator? How likely is that? Plus, the system is highly directional. With an IR laser, anyone more than a degree or two off axis isnt' going to hear shit as long as you're not bouncing the beam off a mirror.

And the mask is SUPPOSED to "trap" the sound of your voice. Otherwise someone might hear it with a "bionic ear" sound amplifier.

<small>[ November 06, 2002, 03:20 AM: Message edited by: nbk2000 ]</small>

Jhonbus
November 6th, 2002, 01:05 PM
Perhaps Afterrain means that a laser mic could be aimed at the mask, picking up its vibrations. This is all but impossible. Laser microphones are extremely difficult to set up even in advance and for a stationary flat surface like a window. To set one up on the fly for a complex shape like a mask, and one that is moving around with the user's head? Not going to happen.

nbk2000
November 6th, 2002, 03:15 PM
If they could get a laser lock on your head, I doubt they'd be doing so to listen in on your conversation. <img border="0" title="" alt="[Wink]" src="wink.gif" />

PYRO500
November 6th, 2002, 05:38 PM
Funny that NBK should mention the "bionic ear" sound amplifier, I happen to own one and the bionic booster dish :) .
It cost me something like $180 or so at the time to get it and in my opinion you could do better. If I were to remake it i'd add some kind of insulation in the hand guard so your movement vibrations are less audiable. I've also found the dish is lacking in effectiveness as I can see the microphone is not at the virtual focal point of the device. Still it does the job and has a nice jack for my tape recorder.

I remember seeing a few circuits a while back in some of my electronics books about amplitude modulated light decoders, IIRC they were simple almost nothing but an audio amplifier that can take the output state of a photo transistor.

Amplitude modulating light is a tiny bit tricker but not much more. If you have a laser than you can modulate it's power supply and make it output the signal into the beam witch through optics can be diverged for a small area or recevability. Also with NV goggles the near IR laser is probobly gonna be visable in the air so you can aim it pretty well.

Both of these I have schematics for. later tonight if I have time I'll post em.

PYRO500
November 6th, 2002, 09:49 PM
I just found circuits for encoding and decoding IR light although the circuits are designed to drive and IR led and a phototransistor, there is no reason you can't substitute a transistor to drive a power supply for an IR laser.

<a href="http://members.tripod.com/xexorz/schematics/irreceiver.html" target="_blank">http://members.tripod.com/xexorz/schematics/irreceiver.html</a>

<a href="http://members.tripod.com/xexorz/schematics/irtransmit.html" target="_blank">http://members.tripod.com/xexorz/schematics/irtransmit.html</a>

<small>[ November 06, 2002, 08:50 PM: Message edited by: PYRO500 ]</small>

SATANIC
November 6th, 2002, 11:18 PM
I think the best and easiest way to communicate silently is field signals. They are (obviosuly) silent, extrememly easy to learn, are very easy to modify to personal needs / scenarios, and can be used anywhere, anytime, providing you have hands..... :rolleyes:

However unlikely, with electronic methods of transmission, there is always the (if only vauge) chance of an outsider listening in. This is also a problem for hand signals, because of course anyone who sees you can see what you're trying to communicate. This would only be a problem though if you used standard signals. If you created your own, there would be no way for your foe to interperet them correctly.

That goes against the whole idea of field signals, because to make them easy to remember, they have to be a motion related to what you're trying to communicate.

If anyone wants a copy of the australian army field signals, I can scan them in in the next couple of days.

I know I've taken the low-tech, not very imaginative route here, but I would rather rely on a method of communication that is always going to be reliable. That, and I can't afford any of the gucci gear.... <img border="0" title="" alt="[Frown]" src="frown.gif" />

nbk2000
November 7th, 2002, 12:12 AM
"Gucci Gear...for the fashionable soldier" <img border="0" title="" alt="[Wink]" src="wink.gif" /> :p

Problem with hand signals is the inabiilty to use them in the dark, when any sensible crimi...I mean terr...oh, uhmmm...law enforcement officer (yeah, thats it! :D ) would be operating.

And it's not expensive to make a light demodulator. I made one from radio shack parts for under $15. Could have been less if I'd made a circuit board for that sole purpose.

Modulation wouldn't be much more. The laser diode would be the most expensive thing to buy.

SATANIC
November 7th, 2002, 12:37 AM
lol NBK, too true. Lucky the true soldiers don't need the gucci gear.

I'm going to scan the field signals anyway, for personal use, so at the same time I'll look up "Methods of night observation" which I had to teach on the weekend. A lot of junk about how the eye works, but focused on how to improve night vision, and how to avoid loosing it.

An interesting read at the very least. I'll post a link to it here when I get it done.

We did test the methods put forward in the pam, and they do work quite effectively. On a night with any moon at all, signals could be clearly understood and replied to effectively over nearly 200 metres.

If it really is that cheap, then I'll be looking at making my own. I was going on a reasonable quality night vision monocular for around $250.... which was as far as I got shopping for that sort of gear.