hcfman

20 ms·

331.
by hcfman 2y ago
I just use the opensoundscape library that can use as many sound sources as you like in the equation.
332.
by hcfman 2y ago
My project, sbts-aru, https://github.com/hcfman/sbts-aru uses a GPS to synchronise the time with and then even when running completely disconnected from any network the clocks will be accurate to real time with less th
333.
by hcfman 2y ago
Relatively open is also okay when they killing small players off. Excluding government usage is hardly very closed. Honestly some folks have worked for years on open source software, that government also benefited from, only to find that no
334.
by hcfman 2y ago
Perfect!
335.
by hcfman 2y ago
I think they shouldn’t make exceptions the police and military. These are precisely the areas where maybe you do want controls. It’s just like the European snooping charter that exempts politicians.
336.
by hcfman 2y ago
Yet another EU law that disadvantages small players in favour of large players by raising the cost to entry. They seem to have forgotten the legions of small players that played a big role in building this modern world. And just like the cy
337.
by hcfman 2y ago
In 1982 I was in love with the 68000. I built a 10 MHz wirewrap board that had 48 chips from memory and used a 68010 chip. It had 4K static ram. My main computer was a Heathkit Z80, 2 MHz. I had to write an assembler for the 68000 in Pascal
338.
by hcfman 2y ago
I built one of the first national search engines in the Netherlands around this approach around 1999, called Search.NL. I’ve placed the code on GitHub for posterities sake. The code doesn’t doesn’t compile anymore. https://github
339.
by hcfman 2y ago
Actually, chatgpt says that for 1mm resolution you need 9 decimal places anyway :-) Note a rtk gnss can resolve your location to 1cm. I don't know how much jitter there is in the USB buffering, but for this purpose, lets assume 0. Then
340.
by hcfman 2y ago
I guess I could ask chatgpt how many decimals gets you to cm accuracy and fix the decimal places to that. Haven’t found it a priority yet. But if it makes details guys happy. You are not the first to say this.
341.
by hcfman 2y ago
Quite possibly just simple ntp may work as well. The radio signals are intended I assume for human hearing.
342.
by hcfman 2y ago
Oh. I’d like to point out that the localization algorithm itself that I use comes from the lovely opensoundscape project from Tessa Rhinehart and friends from the University of Pittsburg. A big thanks to them for their lovely project. http
343.
by hcfman 2y ago
Manually it would do. You can use Raven software to locate the booms.
344.
by hcfman 2y ago
Temperature is already a parameter. Apparently humidity doesn’t have quite such an effect. In the example further down the page where I attempt to work out where the air cannon was fired from, the “1” is for 1 degree Celsius.
345.
by hcfman 2y ago
Nice! I want to try and get something like that going as well.
346.
by hcfman 2y ago
Indoor and thus smaller distances means time accuracy becomes much more important. In my software chain there is a very small bit of uncortekated latency due to unknown buffering size of the USB driver adding to time inaccuracy potentially.
347.
by hcfman 2y ago
Yeah. I want to play with cross correlation next. That could be super interesting.
348.
by hcfman 2y ago
Over really long distances the time inaccuracy makes less difference so indeed a phone can do interesting things. I’m a person that likes extremes so the extremely accurate clock time I could get with a GPS synched Oi really appeals to me.
349.
by hcfman 2y ago
Sad but true. The world is full of so many places like this :-(
350.
by hcfman 2y ago
Interesting. That looks like a system that uses phase difference. Last weekend I localized an explosion to within 20m when two of the microphones were 3 km apart. I went to the location and they were firing fireworks as part of some religio
351.
by hcfman 2y ago
That was indeed a great movie.
352.
by hcfman 2y ago
In reference to that "Finding the Air Cannon" article. The author indicated the following facts: * His listening posts were part of a triangle with sides of length 3.8km, 3.0km and 6.3km * The vertices were on the roads in Corvall
353.
by hcfman 2y ago
Sorry. My reply to this are in the comments above. Thanks for posting, this is a nice read. And also points out that the longer the distances involved the less critical time error is making mobile phone time of arrival viable.
354.
by hcfman 2y ago
Note also, although my project details the construction of a Raspberry Pi recorder for high accuracy localization. If you are localizing over long distances and you are happy a second or two inaccuracy from the arrival times, then indeed yo
355.
by hcfman 2y ago
That’s a nice read, thank you for that. If he sets up three or more recorders then next time he can find out within minutes of the first bang to within meters. But his article presents a fun challenge. He doesn’t say where his receiver loca
356.
Long distance sound localization with the Raspberry Pi(medium.com)
152 points by hcfman 2y ago|40 comments
357.
by hcfman 2y ago
Nice to see people able to use tech to help reduce/manage their stress/trauma in such horrific situations. Good point about telegram. As much local control as possible is desirable. Do the text to speech interfaces work offline wi
358.
by hcfman 2y ago
My WOW with cpio is pretty elementary. I've never found anything in all my usage to shudder about. Possibly there are smarty pants usages in there that could make you shudder I don't know. But why choose smarty pants if elementary
359.
by hcfman 2y ago
The cost of a nuclear power plant is enormous. Surely they can buy a hell of a lot of batteries for the cost of one of those things and the maintenance costs thereof? The current leaders in the Netherlands also want to start projects for ne
360.
by hcfman 2y ago
It’s funny how tar came out first. Then cpio came out which was a lot better but tar had the momentum and it never lost it. I still find cpio more controllable and use that as a preference. But cpio existed when I first used Unix in 1982&#x

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