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Whistled Platform Upgraded With Word Recognition

Unknown Lamer posted about 10 months ago | from the light-switch-kree dept.

Hardware Hacking 30

An anonymous reader writes "A few weeks ago, Slashdot featured a cheap platform performing 80FFTs per second to recognize whistles. The platform is open hardware/open source and is aimed for sound processing projects. To this goal, the creator (limpkin) just implemented a simple proof of concept algorithm that will control your lighting once the platform listens to a particular word. A small video has been made to explain the basic concepts of sound recognition to encourage hobbyist to make their own."

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30 comments

Snowden Detector (0)

Anonymous Coward | about 10 months ago | (#44097205)

Just sayin'

Just installed! (1)

Anonymous Coward | about 10 months ago | (#44097215)

I now have a way to wipe all my drives and trigger my thermite detonators incase the feds come knocking.. now i just need to make sure no good looking women come near me so I don't wolf whistle... I think I'll be ok!

"Would you like me to put the kettle on?" (0)

Anonymous Coward | about 10 months ago | (#44097589)

Might also be a problem if one did come close...

awesome (0)

Anonymous Coward | about 10 months ago | (#44097235)

Great to see someone posting something 'open' like this, rather than patenting it & going on kickstarter...

Re:awesome (0)

Anonymous Coward | about 10 months ago | (#44097563)

Great to see someone posting something 'open' like this, rather than patenting it & going on kickstarter...

Yeah, now pay attention because this is highly technical and complicated, mmkay? You see, this is SOFTWARE so it can be copied infinitely at nearly zero marginal cost. That means it can be shared openly on the internet!

Meanwhile the Kickstarter projects featured on Slashdot generally have one thing in common: they involve the production and distribution of PHYSICAL DEVICES. You see, these cannot merely be downloaded. Somebody has to make them from raw materials. There are costs involved here so funding is needed.

There. You now comprehend why this is different.

Re:awesome (0)

Anonymous Coward | about 10 months ago | (#44097977)

Try reading slowly this time:

The platform is open hardware /open source and is aimed for sound processing projects.

They did not HAVE to go open hardware.

Multiple Rooms (0)

Anonymous Coward | about 10 months ago | (#44097391)

Interesting idea, but I think there would be serious scalability problems. Imagine if this was in each room in your home, and the doors to the rooms were open. Whistling in one room would almost certainly trigger the lights in the adjacent rooms as well. You would run into similar issues trying to control multiple lights in the same room independently, unless you started getting into more complex whistle patterns then those shown in the video. In that case you would start to sound like a songbird, or maybe R2D2.

And finally two side notes...
Not for use in emergency situations while eating saltine crackers.
This method of controlling the lights would be extremely popular in the von Trapp house.

Not A Criticism, But... So What? (5, Interesting)

Jane Q. Public (1010737) | about 10 months ago | (#44097409)

In the 1970s, a book was published entitled "How To Build Your Own Computer-Controlled Robot". In fact this was one of the books that first got me interested in computing.

The author of the book, a high-school student, built (with the help of his engineer father, I don't want to downplay that) a small robot that had obstacle sensors, light sensors, and some basic mapping capability so it could find its own charging station (not so different from a Roomba today).

But my main point is: it also had effective voice recognition, for simple commands. And the implementation was pretty simple: the audio input was amplified, then sent through 3 notch filters to separate high, medium and low audio frequencies. Each of the 3 frequencies was digitally sampled at about 40kHz. Repeated samples were averaged and saved in a table in memory.

The CPU (and remember, this was a 1970s-era CPU, if I recall an 8080a or a Z-80 or similar) constantly sampled incoming sounds, and when one sufficiently matched one of the stored templates it meant "command received".

It was a simple scheme, and it worked fine. I don't want to detract from this inventor, but in essence he is doing a similar thing. Except instead of using notch filters, he's using FFTs to do the frequency analysis and build (and then compare to) the templates. The ideas aren't all that different.

But personally, I think I'd prefer the old method, as it demonstrably worked at least as well as this, used only a few $ in hardware in addition to the CPU, and was pretty definitely less compute-intensive to achieve.

Keep in mind: that was 40 years ago. Maybe this newer approach has more potential; I don't know. But it certainly doesn't look much different at this time.

Re: Not A Criticism, But... So What? (2, Informative)

Anonymous Coward | about 10 months ago | (#44097575)

If you can't see why this has more potential, you know nothing about DSP. Yes, for voice, 3 well-chosen fixed bands is mostly enough. But for whistling (as per the original application) or various other sounds, those same three bands will be pretty crap.

Now we could make the 3 analog notch filters tunable via a DAC output, and get good results for one group (at a time) of a wide range of sounds, but that complicates it substantially. Yes, doing it with FFTs uses a lot more computational power -- but when the cheapest microcontrollers commonly used by hobbyists these days are a lot more powerful than the venerable Z80 (FYI, I built a single-board CP/M box back in the day), why in the world shouldn't we use some of that muscle to do more things, and some of it to do the same things better?

Re: Not A Criticism, But... So What? (1)

Jane Q. Public (1010737) | about 10 months ago | (#44097835)

"But for whistling (as per the original application) or various other sounds, those same three bands will be pretty crap."

I'm not suggesting otherwise. I think you're missing my point, which was that THIS was about voice recognition, not whistling, and he is using a high-tech solution for that where a lower-tech, simpler solution might actually be better.

Nor am I saying we shouldn't do it this way. I'm only saying there are alternatives that might work as well for THIS application, which are also simpler and cheaper.

Re:Not A Criticism, But... So What? (1)

TheRaven64 (641858) | about 10 months ago | (#44098897)

I read a different book, in the '80s about things that you could do with a BBC Micro. One of them was a sound recogniser, which worked in a similar way with a 1MHz 6502. Most of this kind of book seemed to disappear in the '90s though, and didn't really start to reappear until recently.

Re:Not A Criticism, But... So What? (1)

K. S. Kyosuke (729550) | about 10 months ago | (#44101543)

Do you happen to remember the title of the book? I'd certainly be interested in that.

Re:Not A Criticism, But... So What? (1)

TheRaven64 (641858) | about 10 months ago | (#44103737)

I don't, I'm afraid. My school had a book shelf full of books of fun projects involving the BBC, and this was one entry in one of them.

Pre-set command word.. (0)

Anonymous Coward | about 10 months ago | (#44097467)

"Sexy Time"

Oblig. Demolition Man (2)

BlueStrat (756137) | about 10 months ago | (#44097693)

Simon Phoenix, after reprogramming Dr. Cocteau's house lights;

"Nah, I changed that."

"Illuminate"

"De-luminate"

"Ah, Isn't that much better?"

(I swear, the US is looking and feeling more and more like the fictional "Greater SanAngeles" from the movie with every day that passes.)

Strat

Captain Crunch... (0)

Anonymous Coward | about 10 months ago | (#44098017)

...where is that phreak now? What's his take on this?

They have been shut down (1)

jblues (1703158) | about 10 months ago | (#44098181)

Unfortunately the US has charged them with espionage, cut off their funding. And they have been forced to shutdown.

yes but- (0)

Anonymous Coward | about 10 months ago | (#44100491)

I want to hold out for snapping. Is there such a thing?

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