purchased an ipad mini for the singular purpose of running foreflight on it - an electronic flight bag application which replaces a whole bunch of frequently updated aviation charts and printed material, gives convenient access to aviation weather data, simplifies managing a digital logbook, plus lots of hand-calculations like weight and balance that are not difficult but are more annoying to do by hand. in flight the ipad sits in a claw mount sunction cupped to the canopy where it's easy to keep an eye on adsb traffic, pull up airport information, and so on. there are other EFB apps that will run on android tablets but foreflight is more or less the standard and default used by most people so far as I'm aware.
since owning it i've found it's also very handy in the kitchen for viewing recipes as it can be set in place and read without being picked up in the hand as a phone might require.
I think if you time your destructive interference to the source of the audio perfectly and cancel out the sound, you haven't gotten the whole picture. As sound travels away from the source it reflects off surfaces and some of those reflections also reach the microphone. Those sounds have traveled a different distance than the original source and are no longer timed with your interfering element. Imagine holding your hand to block your direct view of a person in a house of mirrors but you can still see them in the mirrors. On top of that these reflections won't contain identical audio as the surfaces will absorb different spectral content, so now even if you had infinite perfectly timed anti-signals for each reflection, your anti-signal has spectral content that is missing from the incoming reflected audio and now your anti-signal is a signal unto itself. In order to create a signal that perfectly cancels out all of the copyrighted audio you would have to have knowledge about the form and materials of the physical environment as well as the position of the microphone within that environment.
In the end, the solution does not have to be perfect. Just have to hide the song well enough so the content ID cannot be made. As you say, the sound that will manage to bypass the "inverted balanced-like filter" will be distorted and hopefully content ID is not accurate enough to recognize it.
you can still get around this with some effort [1] and a pfsense box, the pfsense box gets wan from the ont and the original att router is hung off a third nic where it's allowed to do 802.1x and nothing else. the setup was a little challenging at first but has been maintenance free since. maybe there is a technical reason they have their network set up this way but i was offended at the idea of being prevented from using my own router.
I'm a non-academic taxpayer trying to read articles and don't have access through my employer or public library. I know other people in the same situation. Emailing the authors directly to request a copy is a known legitimate workaround, but in cases where I'm trying to read a paper on fungal propagation from 1971 (most recent example, from last week) the options are limited.
I would also imagine that if these things were more readily available people would be more likely to use them.
Something that bugs me about this metaphor is the foregone conclusion that the thing on the ground is identifiably a $100 bill. Clearly anyone seeing a great idea for the taking will do so, but the discussion is really more comparable to seeing a bit of trash on the ground and pondering whether it might be money or not.
The issue is having ideas but not the ability to determine whether they are good ideas nobody has capitalized on yet or bad ideas that others have abandoned. I find myself asking this question often about a lot of things -- am I somehow so fortunate or clever that I've conjured a great idea, or do I lack the clarity of thought or prior knowledge to understand why my idea is bad, useless, or somehow infeasible?
FWIW, the quote about money on the ground initially comes from a critique on the efficient market hypothesis, not commentary on the nature of ideas. So it's expected for there to be analogical disconnect here.
For it to work as intended, you'd have to construct (or buy into) some framework for an "efficient marketplace of ideas."
Absolutely and I am aware of its origins, but I've seen the analogy brought out at least a few times here on HN when discussing the merits and potential of an idea that seems obvious but has gone unexplored or uncommercialized. I get the sense that there may be some beliefs around the evaluating of ideas, at least in this crowd, that lead some to see it as being comparable to noticing a sum of money on the ground. I'd love to understand that.
Furthermore, I've seen it used in the context of hidden transaction costs in the markets. For example, you see security A trading at $100 on exchange X but $105 on exchange Y. You think "free money!" but on closer examination exchange Y charges $5.01 to transact. These are totally nonsensical numbers, but they do extend to the analogy on ideas.
i've always seen the flashy computer bits as something that isn't intended to be viewed literally, but rather a way to understand the mental models they had for things. in the same sense that i would explain something as "hopping into a box and poking around systemd to see what's on fire", the movie used big flashy graphics as a metaphor for the minds of expert users. i think that was the best possible choice to bring you into their world without requiring the viewer to have an expert understanding of the inner workings of a computer.
i think it was a really good choice, i'm certain i'm not the only person who saw that movie as a small child and decided thats what they want to be. it was exciting and cool back then and it still holds up now. i want to imagine that someone truly and deeply understood having a love and understanding of computer systems when they made the choice to express it with such artistic license.
I worked on a project that used QnX for large volume message transmission via custom telex interfaces. Millions of messages on a good Monday morning. Because I like my development machine to run the same OS as the servers I ended up using it for my daily driver for quite a few years. In the end I liked it so much that when Quantum Software dawdled on their 32 bit implementation that I wrote my own version of the OS.
One really neat demo was 250 windows running the size of poststamps with a little bouncing line demo inside them. All still received their 'fair share' of time, all could still be moved around and expanded as though the machine was otherwise idle.
That's the scheduler. There are a lot of moving parts to running this code, I may make a little project out of restoring it to life under a VM at some point.
Happy reading.
Edit: reading it myself, wow, my English was cringe worthy back then. Moving to Canada certainly fixed that.
Awesome. Thanks. FWIW, I think there's still a place for 32-bit OSes if you never port to 64-bit. Small devices, IoT, or this mc68030 thing I've been building. Lot's of opportunity for fun.
Sure, but if I'm going to spend that much effort I might as well make it future proof. The first iteration of that project cost me two years of my life, and that was when I was 27. To do this again today would be on a relative scale a much bigger investment in the time that remains.
That's just another user process. So everything else will continue. You have to let go of your macro kernel mindset if you want to make sense of the timing in a micro kernel environment. Blocking threads is fine. Just make sure that you don't do that sort of stuff in your UI thread and you won't even realize there is such a thing as disk or network IO.
Mouse, keyboard, screen. Those are the things that should run at high priority. Everything else can - quite literally - wait.
Ah yes, of course. Sorry, I wasn't thinking clearly, just had the usual UI loop and regular interaction with a computer in mind, you are 100% right, audio should have a very high priority. Nothing more annoying than dropouts. Incidentally, the way most OSs deal with that is by having very large audio buffers which in turn will give you terrible latency. On a hard real time OS you could reduce the size of those buffers quite a bit because you can guarantee they are filled (and emptied) regularly.
This is not straightforwardly true. Using small buffers and real-time scheduling works, but it gives terrible power efficiency on a modern high-performance CPU. What you actually want is a scheme with large buffers that can throw out those buffers if something requiring low latency happens.
A lot of usecases require the audio to be low latency all the time. And I don't just mean professional recording studios or musicians, super mainstream things like gaming (especially VR) are way more immersive with low latency audio.
And video conferencing also gets a lot easier, echo cancellation is so hard when you have a lot of data in flight because you will have to do auto correlation on a much larger amount of data.
Well, consider search-as-you-type - you're typing, this goes into some kind of a query into a database. How should the whole UI react ? Display entered text, without updating search results ? Reflow it with best match when results arrive ?
hardly limited to the 1960s, you can still do this in 2020 even in an expensive place like los angeles. pandemic aside, people living cheaply with many roommates and getting by on the wages of a bartender or minimum wage film set production assistant aren't even rare - the old pabst brewery on the eastern fringe of downtown LA is an entire campus of it. it just requires compromises on things that one is less likely to make if $2000/mo/bed is an option.
since owning it i've found it's also very handy in the kitchen for viewing recipes as it can be set in place and read without being picked up in the hand as a phone might require.