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Comment: Re:Creepy (Score 1) 62

by harrkev (#47434677) Attached to: DARPA Successfully Demonstrates Self-Guiding Bullets

You got it. Lasers are cheap... electronics are cheap... batteries are cheap... spoofing is cheap.

Really, as an engineer, I can imagine two ways for this thing to work, and it depends on if the projectile spins. Typically, bullets spin so that they act as gyroscopes -- always pointing the same direction (YouTube has videos of guys firing pistols into ice -- ice stops bullet which just sits there and spins like a top).

If the projectile spins, you can, in theory, guide it with a single fin that can extend or retract. You could not use a standard camera as such, because you are spinning wildly. Assume 2000 FPS bullets -- if you want to shoot a mile, you need at least this much. Also assume a 1-in-12 twist (real twists are in the range of 1-in-7 to 1-in-14, depending on shape and weights of bullet). That means that the bullet is spinning with a approximate rotation of 2 KHz. I doubt that you could have an effective regular camera spinning like that and still work. A better way would be to have a linear sensor (a line camera) that looks forward and to the side. This could operate. When you see a bright stop, see how far it is from the center. More off-center = kick your fin a bit more. This is simple and straightforward. However, since the bullet is spinning and you do not know when the camera will cross the laser, you probably need to keep the laser on full time. This is probably the easiest and cheapest way to accomplish this, but should be easily spoofed. You could maybe put a crypto on the laser signal by changing the intensity of the signal without turning it off, but it would have to be a much lower frequency than 2 KHz because that is your effective sample rate. If you assume 500 Hz signal (four-times oversampling), you would only get about 500 bits of data before you hit your target (assuming a target 2000 feet away). Is that enough to actually apply crypto? I am not sure...

On the other hand, if the bullet is NOT spinning, you can use a regular camera and regular fins to control it. In that case, it is entirely reasonable to embed some sort of cryptographic modulation on the signal. In any case, the existence of a 2-D sensor makes the bullet more expensive, and increases the amount of processing that needs to be done. It should, however, be more feasible to put crypto, but at greater cost.

Comment: Re:Alternate use for this technology (Score 3, Insightful) 62

by harrkev (#47434367) Attached to: DARPA Successfully Demonstrates Self-Guiding Bullets

I don't get the US. I mean, by now you should have noticed that the bigger and more complicated the technology, the more you play into your opponent's hands. First of all, you're using high tech weapons in a low tech war. You can't really fire any round anymore that doesn't cost you more than what your target cost your enemy.

Off topic, I admit, but this reminds me of the current Isreal/Hamaas conflict. Just launch simple, dumb, and cheap unguided rockets from the Gaza Strip. Isreal has an "Iron Dome" defense system that is supposedly pretty effective at stopping them -- at $1,000,000 per shot. Great way to bankrupt an enemy...

Comment: Re:Creepy (Score 2) 62

by harrkev (#47434329) Attached to: DARPA Successfully Demonstrates Self-Guiding Bullets

Actually, this should not be scary at all! You just need to figure out the frequency and modulation of the laser used. Then, just make sure that you have such a laser pointed at the guy beside you. You are suddenly safe from snipers! Just make sure that you do not like the guy beside you.

Seriously, the only way this could be spoof-proof is to modulate the laser with some type of crypto.

Comment: Re:Why 80% (Score 1) 152

by harrkev (#47433621) Attached to: William Binney: NSA Records and Stores 80% of All US Audio Calls

Hey, Obama promised "Hope and Change." Isn't that what we have here? Admittedly, Bush started this -- probably. Or maybe he inherited the seeds from Clinton or earlier -- who knows how far back this trail goes? But Obama has had almost 6 years to fix things. Instead, under his watch, things have gotten worse.

In Obama's defense, I do not know if Romney would have done things any differently, but I suspect we would probably still be here even if he had won.

Privacy

William Binney: NSA Records and Stores 80% of All US Audio Calls 152

Posted by Soulskill
from the must-use-a-good-compression-algorithm dept.
stephendavion sends a report at The Guardian about remarks from whistleblower William Binney, who left the NSA after its move toward overreaching surveillance following the September 11th attacks. Binney says, "At least 80% of all audio calls, not just metadata, are recorded and stored in the U.S. The NSA lies about what it stores." He added, "The ultimate goal of the NSA is total population control, but I’m a little optimistic with some recent Supreme Court decisions, such as law enforcement mostly now needing a warrant before searching a smartphone." One of Binney's biggest concerns about government-led surveillance is its lack of oversight: "The FISA court has only the government’s point of view. There are no other views for the judges to consider. There have been at least 15-20 trillion constitutional violations for U.S. domestic audiences and you can double that globally."

Comment: Re:USB DACs (Score 5, Interesting) 440

A USB audio interface also lies outside the electrically noisy interior of a PC chassis.

Strong caution with USB audio. There is a metric buttload of cheap USB adapters, While they technically work, they typically lack analog filtering that gets rid of higher harmonics. If you look at the output on an oscilloscope, instead of a smooth wave, you see the actual steps. Better audio hardware should have filters to smooth this stuff out.

Another MAJOR thing is inducing noise into the output. This is not just for USB cards, but all audio solutions. You need some pretty good filtering between the digital and analog power domains -- yet another area where cheap sound can skimp. Hey, let's shave $0.05 off by dropping this capacitor and inductor!

The original article really touches on two separate areas:
1) Audio processing
2) Higher quality audio circuitry

SoundBlaster (and other gaming-oriented cards) typically do both. However, do you really NEED both? The audio processing stuff is supposed to provide an API that games can use to make thing sound more realistic, or offload audio processing from software to hardware, or both. It can typically decode various dolby flavors, and do some other fancy DSP-ish type stuff. Do you really NEED all of that? If so, then maybe a gaming card is for you.

However, what if you want the best sound possible, the lowest noise possible, and don't really game or use the various audio enhancements? You just want a plain-vanilla sound card, but with the highest quality audio. Where to do? Skip the computer store, but go to your local MUSIC store (not the ones that sell CD's, the ones that sell GUITARS). Those cards skip all of the DSP bells and whistles, but have the best-quality DACs and filtering that you can find. You can find some really good USB solutions that will blow on-board audio out of the water for about $100 or so. Of course, you can go crazy and spend $500 or more if you want. If it is good enough for a music producer to use in a studio (who makes his or her living off of the sound), it is probably good enough for YOUR music and movies.

Comment: Over-reacting ISPs (Score 1) 148

Most seem to over-react and require an official counter-response

That's because the law requires them to do this. They must either take down the content, or you must provide an official counter-response. There is no 3rd-option of saying "This request is bogus, ignore it" even if it actually is bogus.

Comment: Re:wait (Score 3, Interesting) 238

by MobyDisk (#47371981) Attached to: Following EU Ruling, BBC Article Excluded From Google Searches

They didn't remove the article entirely.

we are no longer able to show the following pages from your website in response to certain searches on European versions of Google:

They don't say which searches, but the wording implies that searches for Stan O'Neal will be affected. But searches for the former CEO of Merril Lynch should work just fine.

Comment: Re:Pivotal Decision That Went The Wrong Way... (Score 2) 238

by MobyDisk (#47371449) Attached to: Following EU Ruling, BBC Article Excluded From Google Searches

Would a 20-year old news article about getting into a bar fight really need removal? That isn't going to keep the person from getting a job or something. Someone who judges people from 20-year old charges isn't worth working for.

The power to arbitrarily remove someone else's published works is horrible - it's like the 1st amendment in reverse. There's no legitimate reason for that, and this example of a wealthy person trying to hide their laundry is proof.

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