They are pimping the fanless celeron version, which uses the Cu128 core. In fact THAT was Intel's greatest MIPS/Watt CPU line. Underclocking 766E MHz Celery is good for the environment, and it still 0wnZ at most FPS. The P4 puts out a lot more thermal energy and only gets marginally better performance. It may dissapate heat better (thus run "cooler") because it has a larger die area, but it puts out more thermal energy total.
Remember, you can even cool an Athlon passively as well, it's not too difficult. But I wouldn't recommend doing that inside a space of a paper-back book!!! ^_^
It started with this comedian (Yakov Smirnov) who made jokes about the US vs. dead USSR right after the cold war. In particular the jokes would switch subject and object around the verb (which you can do by accident if you're Russian struggling with English). For example, "in South Cali, you can always find a party. In old Soviet Russia, the Party finds YOU!!!"
In any case, this was picked up by Family Guy and The Simpsons recently, involving a russian language feature of one of those navigation computers in a car. I assume this is where the Slashbots picked it up. Trolls use it at the drop of a hat now, without thought.
I, on the other hand, am genuinely trying. ::coy smile::
PS - The believe whole "insensitive clod" thing has an origin on British TV of yesteryear, and then later in crusty manpages and fortune files. It surfaces on slashdot because we're into that sort of crap. We spell demon with an æ (aelig) too!
Or perhaps they are the same person. All the better to avoid being modded into oblivion.
See also SexyKellyOsbourne.
Holy crap you don't know JACK about SCSI
on
IDE RAID Examined
·
· Score: 2
Sure, it's a parallel cable. But only one device can communicate with the host at once. It's a lot harder to squeeze 100% of the theoretical bandwidth with 8 slow devices than with 4 fast ones. So the parent's comment was mostly accurate.
There aren't ANY free lossy codecs that can do bit-peeling right now. Some non-free codecs allow you to overlay data (like progressive JPEG), which is NOT the same thing. That's just like transmitting deltas at higher compression rates, which could be done with a simple side-band for any existing method, MP3 even.
The only option is transcoding, which compounds compression errors (decode, reencode). I often wished the MPEG group would have been more intelligent in the design of their bit-allocater so that you could "thin out" the quantization of the power bands by looking at the "right parts" of the MP3 frame. Alas, this is not possible.
But the Vorbis designers have made this possible, thus making it possible to have high-quality and low-quality versions derived from the same source file without additional processing. I imagine you have certain restricted choices, due to how quantization information is bundled up/packeted. But it isn't just sexy, it would be stupid to NOT DO IT. It takes just a little forethought on how to lay out the information in a hierarchial fashion. What makes anyone think that this is any harder then decoding/reencoding. I guarantee it has a time complexity on the order of a straight copy.
Hell, formats like SHN and FLAC can do it, just substitute short codes for long codes at a certain rate; it'll add a bit of wide-band energy on decode, raising the noise floor in proportion to the space savings you gain.
So anyway, "poop on you" to all these wanna-be audiophiles/slashdot-know-it-alls who don't no a good thing when they see it.
On many architectures, intel included, you can grow the stack in either direction. However, the thing here is that Plan 9 always uses stack-grow-down, and it omits frame pointers. They aren't strictly necessary on Intel either (-fomit-frame-pointers) but it can make code undebuggable. Furthermore, this doesn't fix the problem. If you know how far up the stack to manipulate, by overwriting into the next stack frame, you can still cause Plan 9 to jump to malicious code on return. But then, it probably won't do anything interesting without superuser. ^_^
Take AI for example. Most AI problems can be expressed as searching through some abstract space for a solution.
Ummm, maybe. That approach does work with chess, but it hasn't exactly been generlisable to much else.
Nearly all AI problems that have state-based models (natural language processing, chess, go, other n-player adversarial games, pathfinding, knowledge systems and logic nets, solvers) use searches through abstract space. The methods of choosing where to look and what not to look at are sophisticated, but it comes down to enumeration and guess/check in the end. Clearly, QC would give us an edge in such applications. It has wide-reaching impact on AI.
Fortunately, this bug didn't make it into 2.5 so it won't be propogated forward. Hint: the quick fix ISN'T a quick fix, it doesn't work. Either stick with 2.4.19, don't use journaled file data, or sync before umounting (I do that anyway... just superstitious I guess ^_^).
It will take a few days to add some extra magic to the umount logic to flush all buffers in an intelligent way. Hopefully this optimization is worth the effort for dudes with high-uptime.
- Is M$'s "Trust Worthy Computing"... DCMA become a "national priority"?
Like all things Microsoft, it'll flop at first only to exist later (after sinking much money into it) as a metastable compromise targeted at Joe Consumer, whereas "professional" computing will remain relatively unaffected (but with increased hardware costs... no sub $1000 video editing PCs). The DCMA will have undergone judicial review and some of the clauses rendered harmless in the aftermath of a hotly contested case.
- Will the RIAA... works across the 'net? Yes, the RIAA will move to Internet distribution. It will tie into state of the art DRM technology. Of course, we'll all go back to using IRC and sftp to distribute files. P2P will still exist, but it will have become more like a business tool. They will start to resemble advanced implementations of CodaFS.
- Will 64-bit CPUs be common, and AMD the one leading in this sector? Yes, and no. 64-bit will become popular because its OBVIOUSLY better than 32-bit. No one will introduce 128-bit sized words because we don't have 2^64 discrete things to count in the universe (this EXACT argument will resurface as engineers loathe routing unnecessary traces on the die). AMD will hemmorage money and eventually be bought by Hitachi where they continue produce awesome CPUs that no one will ever know existed. (SHA4, for example).
- Will Apple finally release OSX on x86 hardware? That'll happen much sooner than you think. 10 years from now OSX will be old and crusty. Can't say what the new hip thing will be, except, it'll be UNIX based!!! ^_^
blah blah blah Microsoft won't die. It might buy General Electric and enter the home appliance market (of which the PC is just one...)
Linux will continue to exist, and someone will package it with and easy to use desktop. They will not make the same mistakes Lindows does. It will involve at least one ex-Be software developer and a graduate student studying user interface design as her doctorate specialization.
Linux installations will still confined themselves to something approxmating 1/2CDs, but it will come with the latest snapshot of every sourceforge hosted project on an extras DVD.
The source to core of windows NT 5.x will be released to everyone once version 7 is ready. They will also open DOS so that we can all see how bad it really was back in the stone age. Microsoft figures if they ain't supporting it, it would be a good gesture to give it away (since its useless as far as they're concerned). This will occur only after the untimely death of Paul Allen.
The purdue scientists know what stippling is. They point is they found out how to transform voxels into 3d stipples that look good from multiple directions... not stippling in the screen coordinate sense. So how is Carmack suddenly a pioneer of medical imaging?
The first thing to do is expose all of your drives in the "same format". On Windows machines, share the extra disks as normal. In linux, use NBD (network block device) or iSCSI to expose the disks as raw partitions accessable over ethernet to the other linux boxen.
Now, on a special linux machine (the sucka, or Serialization and Uniformity Cache Kludge Administrator) mount all these exposed drives via "mount.smbfs" for the windows boxen. Use loopback filesystems the size of each Windows disk to create virtual devices accessable on said remote winboxen. Use md or LVM to stitch the exported linux box disks and loopbackfs-over-smbfs together into a software RAID disk.
Finally, format this UBER meta disk via your favorite filesystem. Expose it to windows via samba, and linux via NFS.
Of course, this whole setup serializations all the operations through one machine. Everything takes one round trip over the network. And unless you use RAID striping, if a machine goes down, so does the whole disk!
Other method, more complex:
Check out the Parallel Virtual Filesystem. What you do is for each spare linux box that has a disk, you run both the IO server and a client. One machine also has to pick up the slack of the metadata manager (no big deal...) Of course, for each linux machine, you have to pick and mount certain the Windows disks (via mount.smb) and run IO server procs for each mounted volume. Finally, you have to run samba on at least one of the linux machines running PVFS to expose those files back to the Windows machines. If you can tweak the samba source to use larger than normal block transfers, do so, because PVFS suffers when you transfer data between nodes that are too small.
Or you can use OpenAFS. Someone else mentioned it here. But it's not as much fun, and it is a big deal to set up if you haven't done it before.
Maybe you haven't learned about the Internet in ITE 101, but it's bi-directional. You pay for bandwidth, they pay for bandwidth. Just because people who mainly web surf are downloading only doesn't mean jack to backbone providers. Their routers run full tilt in all directions.
There's a way to even the balance out... run a webserver locally. Then you can contribute reciprocally. If everyone did this, then the ISPs would have to realize that they need to start offering symmetric data transfer profiles. Then everyone would be happy.
Or here's an idea, sell something on/with your goddamn website. Don't expect the infrastructure to help you get paid. That's your fucking perogative. Otherwise, get off the web, cheapskate. It's people like you who think they can get rich with their HTML skills without some other kinda backing or PLAN that ruin the Internet.
Perhaps however (in response to the comment below about memory leaks), it would be better to open the popups in an iframe in a minimized and/or hidden window (however this is accomplished by the web browser/OS combination is left up to the implementers).
The document containing the IFRAMES would emulate whole popup windows inside the window to convince each one that they were on top, and then send close events to each of them after a few seconds.
Then, after you notice your smoking crater which used to be your domicile, you call a general contractor to build a new one over the anthill you missed.
I didn't want to start spouting off signal analysis lingo. But apparently around here it gets you karma.
Okay, you bring up a number of interesting points. Record some and run it through your favorite MP3 player, with a reasonably sized FFT filter going in realtime. Not a good idea, MP3 encoding tends to filter out some of the noise... Watch the FFT display jerk spasmodically. Even the wiggling isn't as regular as you think; if you could do an FFT of the FFT, you'd see that. It's noise, it really is, and even if it sounds to your ear like it's "the same" noise, your computer hears it as anything but. But what ultimately matters is what that noise sounds like to the ear, and while we can't eliminate the PC noise entirely, we can compensate for an approximation so that it is all that more pleasing to the human listener. While the traces may "jump around" a lot (which an FFT of an FFT won't indicate clearly), what we want is to have a time-decayed sum of the power spectrum. This averages out (over a few frames) energy drift across bands, and emphasizes the stationary energy that is most annoying. We will probably doing this with overlapping windows, up to, lets say, 50ms long(which more than covers 60Hz hum), and window intervals at 4 times that rate (12.5 ms updating). Noise is really, really dynamic, and you can't predict what it is going to do next.
Exactly. It doesn't autocorrelate, by definition. But then there's the stuff that does... Oh, and there's no such thing as noise cancellation, by the way, only cancelling certain sounds at certain isolated locations. That's why you need two headphones, one dedicated to each ear, to cancel noise. A single microphone cannot cancel noise for two ears across a set of frequencies, period, especially if it doesn't know where those ears are.
Duh. I never said that my idea could lead to noise elimination, just that it could help. Again, don't take my word for it, draw it. Draw equally-spaced concentric circles emanating from a point... blah blah blah...all at once.
Look, the stuff that we're most interested falls below 200Hz, at this point the sound is fairly omnidirectional. So any intelligent compensation will not be in vain. You don't even care about preserving phase. What you're trying to do just a little compensation, allowing the fan noise to fill out frequencies you attentuate in the signal. (During the processing, you don't touch the complex components of the transformed signal, also make sure to window it the same way you windowed the microphone samples for attenuation). Also, there will be issue with expected trip delay, because you might want to be able to do a dry run and see how much contribution (if any) the sound output has on the input to the mic, and what the system delay is. You might want to purposefully filter the filtering information using a delayed copy of the previously outputed sound. And if you're doing that, you'll have to pay attention to clock phase drift between the input and output sections of whatever sound hardware you have (phase unwrapping... ooh fun). Please try these things before trying to pick them apart; human intuition and wave phenomena are notoriously poor bedfellows.
?! I've been involved in projects recently doing things like this in relation to positional tracking using PSKs. I'm not offering a magic bullet or anything. But everyone here has such a bad attitude. Give me a break.
Now as to whether this could become a product marketable to audiophiles... forget it. As to whether it's worth someone's time to write this software because his PC is too noisy... she'd be better off buying quieter fans.
But it's interesting... not a waste of time if you dig that sort of thing. Just thinking about the response is getting me more excited about it.
and I'm glad too. However, I'm saying its entirely possible that all the functionality you want is there.
As to having IPX available to existing code within a dos emulator, probably not. Sorry. But if you can recreate the client in native code, you can talk to the server using the aforementioned guide.
except you'd need a really nice microphone, thus nullifying the effort saved on not buying expensive headphones. But it is possible, unlike what some other naysayers claim. I assume you want to cancel generic PC noise, not everything outside EXCEPT what you want to hear (that is almost impossible to begin without over-ear gadgetry or a fixed-head requirement... get big sweaty headphones instead).
What some other people here forget is that by-and-large, the noise created by a PC's fans are stationary signals. A second of training to the ambient noise in the room via an omnidirectional mic will allow you to build a frequency profile. Then, you filter the data against this profile to compensate for the ambience. Of course, you keep updating the profile, as noise levels in the room are constantly changing. One problem is that you have to deal with processing the sound in the frequency domain to compensate, so you have to transfer to and from the time domain in chunks. This all has to be accopmlished in realtime (it's not light on the CPU) and it will introduce a short delay, but the shorter that delay, the less effective it will be.
I think a better solution would be to place the crappy desktop mic (if you aren't using it for telephony) into the case of the PC, where it will work better. Then you could work on reducing the apparent machine noise (including 60Hz hum!)
Slashdot Mirror
They are pimping the fanless celeron version, which uses the Cu128 core. In fact THAT was Intel's greatest MIPS/Watt CPU line. Underclocking 766E MHz Celery is good for the environment, and it still 0wnZ at most FPS.
The P4 puts out a lot more thermal energy and only gets marginally better performance. It may dissapate heat better (thus run "cooler") because it has a larger die area, but it puts out more thermal energy total.
Remember, you can even cool an Athlon passively as well, it's not too difficult. But I wouldn't recommend doing that inside a space of a paper-back book!!! ^_^
In Sunnydale CA the college students perform quadrature to determine equilibrium human/vampire populations, only if the eigenvectors aren't imaginary.
In SOVIET RUSSIA, the eigenvampires are real and they successfully integrate YOU!!!
It started with this comedian (Yakov Smirnov) who made jokes about the US vs. dead USSR right after the cold war. In particular the jokes would switch subject and object around the verb (which you can do by accident if you're Russian struggling with English). For example, "in South Cali, you can always find a party. In old Soviet Russia, the Party finds YOU!!!"
::coy smile::
In any case, this was picked up by Family Guy and The Simpsons recently, involving a russian language feature of one of those navigation computers in a car. I assume this is where the Slashbots picked it up. Trolls use it at the drop of a hat now, without thought.
I, on the other hand, am genuinely trying.
PS - The believe whole "insensitive clod" thing has an origin on British TV of yesteryear, and then later in crusty manpages and fortune files. It surfaces on slashdot because we're into that sort of crap. We spell demon with an æ (aelig) too!
In SOVIET RUSSIA, the vampires are real, and they are integrating YOU!!!
(They are truely math wizards)
The college students perform quadrature to determine equilibrium human/vampire ecologies.
In SOVIET RUSSIA, the vampires integrate YOU!!!
But the guy isn't an asshole. Just don't take everything he/she says so seriously. Damn funny, IMHO.
Or perhaps they are the same person. All the better to avoid being modded into oblivion.
See also SexyKellyOsbourne.
Sure, it's a parallel cable. But only one device can communicate with the host at once. It's a lot harder to squeeze 100% of the theoretical bandwidth with 8 slow devices than with 4 fast ones. So the parent's comment was mostly accurate.
There aren't ANY free lossy codecs that can do bit-peeling right now. Some non-free codecs allow you to overlay data (like progressive JPEG), which is NOT the same thing. That's just like transmitting deltas at higher compression rates, which could be done with a simple side-band for any existing method, MP3 even.
The only option is transcoding, which compounds compression errors (decode, reencode). I often wished the MPEG group would have been more intelligent in the design of their bit-allocater so that you could "thin out" the quantization of the power bands by looking at the "right parts" of the MP3 frame. Alas, this is not possible.
But the Vorbis designers have made this possible, thus making it possible to have high-quality and low-quality versions derived from the same source file without additional processing. I imagine you have certain restricted choices, due to how quantization information is bundled up/packeted. But it isn't just sexy, it would be stupid to NOT DO IT. It takes just a little forethought on how to lay out the information in a hierarchial fashion. What makes anyone think that this is any harder then decoding/reencoding. I guarantee it has a time complexity on the order of a straight copy.
Hell, formats like SHN and FLAC can do it, just substitute short codes for long codes at a certain rate; it'll add a bit of wide-band energy on decode, raising the noise floor in proportion to the space savings you gain.
So anyway, "poop on you" to all these wanna-be audiophiles/slashdot-know-it-alls who don't no a good thing when they see it.
Don't like it, keep sucking on that Layer III.
linux has dumpe2fs. It is command-line compatible, and functionally equivalent.
On many architectures, intel included, you can grow the stack in either direction. However, the thing here is that Plan 9 always uses stack-grow-down, and it omits frame pointers. They aren't strictly necessary on Intel either (-fomit-frame-pointers) but it can make code undebuggable. Furthermore, this doesn't fix the problem. If you know how far up the stack to manipulate, by overwriting into the next stack frame, you can still cause Plan 9 to jump to malicious code on return. But then, it probably won't do anything interesting without superuser. ^_^
Nearly all AI problems that have state-based models (natural language processing, chess, go, other n-player adversarial games, pathfinding, knowledge systems and logic nets, solvers) use searches through abstract space. The methods of choosing where to look and what not to look at are sophisticated, but it comes down to enumeration and guess/check in the end. Clearly, QC would give us an edge in such applications. It has wide-reaching impact on AI.
JUST DON'T SHUT YOUR SYSTEM OFF! MUWAHAHAHAHAA!!
just kiddin'
Fortunately, this bug didn't make it into 2.5 so it won't be propogated forward. Hint: the quick fix ISN'T a quick fix, it doesn't work.
Either stick with 2.4.19, don't use journaled file data, or sync before umounting (I do that anyway... just superstitious I guess ^_^).
It will take a few days to add some extra magic to the umount logic to flush all buffers in an intelligent way. Hopefully this optimization is worth the effort for dudes with high-uptime.
- Is M$'s "Trust Worthy Computing" ... DCMA become a "national priority"?
... works across the 'net?
Like all things Microsoft, it'll flop at first only to exist later (after sinking much money into it) as a metastable compromise targeted at Joe Consumer, whereas "professional" computing will remain relatively unaffected (but with increased hardware costs... no sub $1000 video editing PCs). The DCMA will have undergone judicial review and some of the clauses rendered harmless in the aftermath of a hotly contested case.
- Will the RIAA
Yes, the RIAA will move to Internet distribution. It will tie into state of the art DRM technology. Of course, we'll all go back to using IRC and sftp to distribute files. P2P will still exist, but it will have become more like a business tool. They will start to resemble advanced implementations of CodaFS.
- Will 64-bit CPUs be common, and AMD the one leading in this sector?
Yes, and no. 64-bit will become popular because its OBVIOUSLY better than 32-bit. No one will introduce 128-bit sized words because we don't have 2^64 discrete things to count in the universe (this EXACT argument will resurface as engineers loathe routing unnecessary traces on the die). AMD will hemmorage money and eventually be bought by Hitachi where they continue produce awesome CPUs that no one will ever know existed. (SHA4, for example).
- Will Apple finally release OSX on x86 hardware? That'll happen much sooner than you think. 10 years from now OSX will be old and crusty. Can't say what the new hip thing will be, except, it'll be UNIX based!!! ^_^
blah blah blah
Microsoft won't die. It might buy General Electric and enter the home appliance market (of which the PC is just one...)
Linux will continue to exist, and someone will package it with and easy to use desktop. They will not make the same mistakes Lindows does. It will involve at least one ex-Be software developer and a graduate student studying user interface design as her doctorate specialization.
Linux installations will still confined themselves to something approxmating 1/2CDs, but it will come with the latest snapshot of every sourceforge hosted project on an extras DVD.
The source to core of windows NT 5.x will be released to everyone once version 7 is ready. They will also open DOS so that we can all see how bad it really was back in the stone age. Microsoft figures if they ain't supporting it, it would be a good gesture to give it away (since its useless as far as they're concerned). This will occur only after the untimely death of Paul Allen.
The purdue scientists know what stippling is. They point is they found out how to transform voxels into 3d stipples that look good from multiple directions... not stippling in the screen coordinate sense. So how is Carmack suddenly a pioneer of medical imaging?
The first thing to do is expose all of your drives in the "same format". On Windows machines, share the extra disks as normal. In linux, use NBD (network block device) or iSCSI to expose the disks as raw partitions accessable over ethernet to the other linux boxen.
Now, on a special linux machine (the sucka, or Serialization and Uniformity Cache Kludge Administrator) mount all these exposed drives via "mount.smbfs" for the windows boxen. Use loopback filesystems the size of each Windows disk to create virtual devices accessable on said remote winboxen. Use md or LVM to stitch the exported linux box disks and loopbackfs-over-smbfs together into a software RAID disk.
Finally, format this UBER meta disk via your favorite filesystem. Expose it to windows via samba, and linux via NFS.
Of course, this whole setup serializations all the operations through one machine. Everything takes one round trip over the network. And unless you use RAID striping, if a machine goes down, so does the whole disk!
Other method, more complex:
Check out the Parallel Virtual Filesystem. What you do is for each spare linux box that has a disk, you run both the IO server and a client. One machine also has to pick up the slack of the metadata manager (no big deal...) Of course, for each linux machine, you have to pick and mount certain the Windows disks (via mount.smb) and run IO server procs for each mounted volume. Finally, you have to run samba on at least one of the linux machines running PVFS to expose those files back to the Windows machines. If you can tweak the samba source to use larger than normal block transfers, do so, because PVFS suffers when you transfer data between nodes that are too small.
Or you can use OpenAFS. Someone else mentioned it here. But it's not as much fun, and it is a big deal to set up if you haven't done it before.
Very few people have been kissed by a cartoon. ^_^.
Be happy!
Sephiroth, goddamn i want you so bad... ::blushes::
you can tweak the Core and Memory bus speeds on a 4200 to match the 4600 if you have adequate cooling. So you have NO EXCUSES!
Maybe you haven't learned about the Internet in ITE 101, but it's bi-directional. You pay for bandwidth, they pay for bandwidth. Just because people who mainly web surf are downloading only doesn't mean jack to backbone providers. Their routers run full tilt in all directions.
There's a way to even the balance out... run a webserver locally. Then you can contribute reciprocally. If everyone did this, then the ISPs would have to realize that they need to start offering symmetric data transfer profiles. Then everyone would be happy.
Or here's an idea, sell something on/with your goddamn website. Don't expect the infrastructure to help you get paid. That's your fucking perogative. Otherwise, get off the web, cheapskate. It's people like you who think they can get rich with their HTML skills without some other kinda backing or PLAN that ruin the Internet.
Perhaps however (in response to the comment below about memory leaks), it would be better to open the popups in an iframe in a minimized and/or hidden window (however this is accomplished by the web browser/OS combination is left up to the implementers).
The document containing the IFRAMES would emulate whole popup windows inside the window to convince each one that they were on top, and then send close events to each of them after a few seconds.
Then, after you notice your smoking crater which used to be your domicile, you call a general contractor to build a new one over the anthill you missed.
I didn't want to start spouting off signal analysis lingo. But apparently around here it gets you karma.
...all at once.
Okay, you bring up a number of interesting points.
Record some and run it through your favorite MP3 player, with a reasonably sized FFT filter going in realtime.
Not a good idea, MP3 encoding tends to filter out some of the noise...
Watch the FFT display jerk spasmodically. Even the wiggling isn't as regular as you think; if you could do an FFT of the FFT, you'd see that. It's noise, it really is, and even if it sounds to your ear like it's "the same" noise, your computer hears it as anything but.
But what ultimately matters is what that noise sounds like to the ear, and while we can't eliminate the PC noise entirely, we can compensate for an approximation so that it is all that more pleasing to the human listener. While the traces may "jump around" a lot (which an FFT of an FFT won't indicate clearly), what we want is to have a time-decayed sum of the power spectrum. This averages out (over a few frames) energy drift across bands, and emphasizes the stationary energy that is most annoying. We will probably doing this with overlapping windows, up to, lets say, 50ms long(which more than covers 60Hz hum), and window intervals at 4 times that rate (12.5 ms updating).
Noise is really, really dynamic, and you can't predict what it is going to do next.
Exactly. It doesn't autocorrelate, by definition. But then there's the stuff that does...
Oh, and there's no such thing as noise cancellation, by the way, only cancelling certain sounds at certain isolated locations. That's why you need two headphones, one dedicated to each ear, to cancel noise. A single microphone cannot cancel noise for two ears across a set of frequencies, period, especially if it doesn't know where those ears are.
Duh. I never said that my idea could lead to noise elimination, just that it could help.
Again, don't take my word for it, draw it. Draw equally-spaced concentric circles emanating from a point... blah blah blah
Look, the stuff that we're most interested falls below 200Hz, at this point the sound is fairly omnidirectional. So any intelligent compensation will not be in vain. You don't even care about preserving phase. What you're trying to do just a little compensation, allowing the fan noise to fill out frequencies you attentuate in the signal. (During the processing, you don't touch the complex components of the transformed signal, also make sure to window it the same way you windowed the microphone samples for attenuation). Also, there will be issue with expected trip delay, because you might want to be able to do a dry run and see how much contribution (if any) the sound output has on the input to the mic, and what the system delay is. You might want to purposefully filter the filtering information using a delayed copy of the previously outputed sound. And if you're doing that, you'll have to pay attention to clock phase drift between the input and output sections of whatever sound hardware you have (phase unwrapping... ooh fun).
Please try these things before trying to pick them apart; human intuition and wave phenomena are notoriously poor bedfellows.
?! I've been involved in projects recently doing things like this in relation to positional tracking using PSKs. I'm not offering a magic bullet or anything. But everyone here has such a bad attitude. Give me a break.
Now as to whether this could become a product marketable to audiophiles... forget it. As to whether it's worth someone's time to write this software because his PC is too noisy... she'd be better off buying quieter fans.
But it's interesting... not a waste of time if you dig that sort of thing. Just thinking about the response is getting me more excited about it.
and I'm glad too. However, I'm saying its entirely possible that all the functionality you want is there.
As to having IPX available to existing code within a dos emulator, probably not. Sorry. But if you can recreate the client in native code, you can talk to the server using the aforementioned guide.
except you'd need a really nice microphone, thus nullifying the effort saved on not buying expensive headphones. But it is possible, unlike what some other naysayers claim. I assume you want to cancel generic PC noise, not everything outside EXCEPT what you want to hear (that is almost impossible to begin without over-ear gadgetry or a fixed-head requirement... get big sweaty headphones instead).
What some other people here forget is that by-and-large, the noise created by a PC's fans are stationary signals. A second of training to the ambient noise in the room via an omnidirectional mic will allow you to build a frequency profile. Then, you filter the data against this profile to compensate for the ambience. Of course, you keep updating the profile, as noise levels in the room are constantly changing. One problem is that you have to deal with processing the sound in the frequency domain to compensate, so you have to transfer to and from the time domain in chunks. This all has to be accopmlished in realtime (it's not light on the CPU) and it will introduce a short delay, but the shorter that delay, the less effective it will be.
I think a better solution would be to place the crappy desktop mic (if you aren't using it for telephony) into the case of the PC, where it will work better. Then you could work on reducing the apparent machine noise (including 60Hz hum!)