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Wikipedia:Reference desk/Archives/Computing/2008 November 16

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November 16

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Can WinXP access WPA2 WiFi networks?

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I have my Wifi 'n' base station configured for WPA2 only and my WinXP machine cannot connect to it. But if I change the base station to WPA/WPA2, XP can connect. Any trick to getting it to access WPA2 only? --69.151.187.196 (talk) 06:08, 16 November 2008 (UTC)[reply]

You need to install this update for Windows XP to support WPA2. Windows XP SP3 includes it I believe; but you need to manually get the update for previous SP's. --71.106.183.17 (talk) 10:19, 16 November 2008 (UTC)[reply]
Also this update, which "enhances support" for WPA2. --71.106.183.17 (talk) 21:52, 16 November 2008 (UTC)[reply]

Virtual 3D Accelerator for Linux

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I just installed Ubuntu 8.10 desktop version on my PC. Unfortunately, my graphical device, SiS 661FX seems to not support hardware 3D acceleration so that the Compiz Fusion desktop effect is not available. Maybe, setting up a virtual machine could solve this problem as it could emulate a 3D acceleration devie (NVida, ATI, etc. graphic cards) on the virtual machine (I'm not sure as I never used it), but VirtualBox requires 512MB memory which my PC cannot satisfies. So I wonder is it possible to make a virtual device driver (for Linux) which can emulate a 3D accelerator and enables Compiz Fusion? - Justin545 (talk) 07:01, 16 November 2008 (UTC)[reply]

Even if you got an emulation of hardware accelerated graphics to work, it would be very slow and you probably wouldn't be able to do anything useful. The only VM software on GNU/Linux that supports 3D acceleration for the guest is VMware Workstation 6.5, but that requires that you have hardware acceleration on the host as well. I don't think there are any "virtual device driver"s out there. --wj32 t/c 07:54, 16 November 2008 (UTC)[reply]
The slowness is expectable. One purpose of my question is to know the possibility. The possibility that whether linux is capable of emulating such a device without changing its kernel architecture. The other purpose of the question is to give me a chance to somewhat experience and tryout Compiz (even if it's extremely slow) and familiar with the settings so that I can decide if I should prepare for my hardware upgrade or remain unchanged. I may stay unchanged if the settings is too difficult or it's not worth. - Justin545 (talk) 08:45, 16 November 2008 (UTC)[reply]
You only have two choices - buy a graphics card (get one with an nVidia chip - ATI are behind the curve on Linux - forget ANY other chip brand) - or you have to resort to S-L-O-W software emulation. The only working, modern OpenGL emulator in existence is "Mesa" - which should already have been installed by Ubuntu (search for 'libGL*.*' in the /usr/lib and /usr/X11/lib directories to see if it's installed). If any OpenGL programs are running - then you have Mesa installed for sure. It'll do most of the things that a decent graphics card can do - but it'll be painfully slow. The features Mesa lacks are optional in OpenGL - so correctly implemented applications should be able to cope without whatever it might lack.
But basically - if you want 3D graphics - buy a 3D graphics card. (The SiS 661FX is a joke - even if there was a driver for it - (which there isn't) it's complete and utter crap). Don't bother messing with virtual machines - they don't virtualize the graphics anyway, they use the underlying graphics API so you'd be back to the SiS 661FX and either no OpenGL or Mesa - which would now be double-slow because of the virtualization.
SteveBaker (talk) 03:53, 17 November 2008 (UTC)[reply]
I'm pretty sure Compiz Fusion checks for DRI; and I'm also pretty sure that Mesa doesn't support texture_from_pixmap properly (which Compiz Fusion requires). --wj32 t/c 05:38, 17 November 2008 (UTC)[reply]
It's been a long time since I used Mesa - and I have never played with Compiz Fusion - but if Compiz doesn't fall back to doing an image glReadPixels or a glCopyPixels to recover from hardware that doesn't support render-to-texture or whatever - then it's not a very well written application and you're kinda screwed. Properly written code should either have fallbacks or very carefully list the hardware it actually needs in order to run. SteveBaker (talk) 05:30, 18 November 2008 (UTC)[reply]

Thanks for you two precious advices. However, please try to be nice in response to other guy's questions and try not to be too emotional. If you think I have any ridiculous misunderstanding about Linux, OpenGL, X Window or whatever, you can directly point out the specific errors I made. I'm just new to Linux system and there are many thing I don't know and make me curious. Pleas don't think that I was criticizing the Linux or whatever I've mentioned. If I didn't like things from Linux community, I would not ask qustion here and try to install it. - Justin545 (talk) 12:24, 17 November 2008 (UTC)[reply]

There was nothing emotional in my reply!...it's the straight truth and it's independent of your knowledge of Linux, etc. SteveBaker (talk) 05:30, 18 November 2008 (UTC)[reply]

No Sound in Linux

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So I recently installed Ubuntu Fiesty onto my laptop (I have not bothered to download the most recent as a distribution update is not that long) and then updated it to Hardy. The laptop is an EMachine. I have no clue what the model is as it just says "EMachine" and the sound card appears to be an ATI card. Anyways, I have all the codecs and I have installed alsa and oss..and a great amount of others. But to no avail. I have no sound and I have searched all over to find a driver or workaround. I am hoping you can make sense of what I am saying at 4:30 in the morning. Rgoodermote  09:22, 16 November 2008 (UTC)[reply]

A better source of help than the Wiki reference desks could be either the Ubuntu forums: http://ubuntuforums.org/ and/or the Ubuntu mailing list: https://lists.ubuntu.com/ . You're much more likely to get the help you need from those resources. Both are packed with volunteers with a great depth of knowledge on all things Ubuntu/Linux related. - Akamad (talk) 01:57, 17 November 2008 (UTC)[reply]
Not being rude..but that last statement was very ironic. I actually tried those two first. The site...well I could not figure out why it would not let me login even though I had confirmed my email and allowed all cookies. The second..I never got a confirmation email from them. So I am pretty much boned. Rgoodermote  05:30, 17 November 2008 (UTC)[reply]

Programme to find chords?

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Hi there, everyone:

Is there a programme that one can use to find chords of an MP3 or other music file. I wrote and recorded some songs a few years ago and forgot the unfortunately complicated chords.

Thanks in advance,

--134.151.33.188 (talk) 12:44, 16 November 2008 (UTC)[reply]

You'll have best luck looking in a MIDI file. If you could find a MP3 to MIDI converter you could easily find the chords, but most mp3 to midi converters are experimental and may not sound exactly as the song itself. Parker2334 16:07, 16 November 2008 (UTC)[reply]
Converting an MP3 file to MIDI is going to take exactly the same sort of computations necessary to just view the chords/notes of an MP3 file. You're just adding an extra step by making it a MIDI file. --98.217.8.46 (talk) 20:09, 16 November 2008 (UTC)[reply]
If you have a song of complicated chords it is unlikely that you're going to be able to have a program extract them automatically. This is the sort of thing that a well-trained human does much better than a machine (which has to do a lot more work to separate out the foreground from the background noise, much less figure out the chord notes). Take it to a guitar shop; their resident guru could probably do it in a minute. (My guitar teacher could do it, anyway, and he was nothing special.) --98.217.8.46 (talk) 20:09, 16 November 2008 (UTC)[reply]
Agreed. However, it can be done in software if you take one chord at a time, see A Hard Day's Night (song)#Opening_chord. Not exactly trivial, however :-). Better to follow 98.217's advice. --NorwegianBlue talk 22:22, 16 November 2008 (UTC)[reply]
Check out Melodyne Direct Note Access. You can see in this 14 minute interview with the creator that the program, besides being able to show you the individual notes within recorded chords, can also analyze the harmony of passages. Just around the half-way point in the interview the fellow gives an example where the program has determined that the passage he's using as an example is in Am. Good luck! --dw

Send and receive Text Messages (SMS) from a computer

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I have a computer but do not own a cell phone. I have many friend who do have cell phones. I want to be able to text them easily from my windows xp machine and have them easily be able to reply. And, of course, I hope to do this free of charge, to me at least.

What's the best way to do this? --Alecmconroy (talk) 14:44, 16 November 2008 (UTC)[reply]

With most instant messaging, you can simply add them as a contact with their username being +[International][AreaCode][PhoneNumber]. For example a USA cell phone could be texted from a service like AOL Instant Messenger with the contact being "+17325551234". Let me know if you have any questions. MatthewYeager 18:58, 16 November 2008 (UTC)[reply]
I just e-mail them. For example, if your friend used Cricket, and their number was 111-222-3333, you'd send an e-mail to 1112223333@sms.mycricket.com. They go through 100% of the time for me. There are also often web interfaces on the carrier's web site to do this, but gets to them faster if you just e-mail them.--Areateeth34 (talk) 19:14, 16 November 2008 (UTC)[reply]

Follow-up: How do they reply?

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Well, my further question would be how do they easily reply back? Ideally, I'd like a solution where they have to have little or no foreknowledge of how to reply. I've had the "computer -> sms phone" part down, but how to do the reply: "sms phone -> computer" is the tricky part.
Any aid greatly appreciated --Alecmconroy (talk) 19:29, 16 November 2008 (UTC)[reply]
Have them send their message to your e-mail address. When they enter you as a contact, instead of entering your phone number, have them enter your complete e-mail address (someone@something.com).--Areateeth34 (talk) 19:49, 16 November 2008 (UTC)[reply]

ImageMagick coordinates after crop

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I want to use ImageMagick to crop a region out of the middle of a larger image and draw a rectangle in the upper right-hand corner of the cropped image. So I tried this:

convert -crop 2050x1475+300+240 -draw 'fill black rectangle 1800,0 2050,300' in.jpg out.png

However, ImageMagick seems to be interpreting the coordinates in the draw command as relative to the original image. I tried using +repage after the crop, but that appears to have no effect. How can I get ImageMagick to treat the upper left pixel of the cropped region as (0,0) after the crop? —Bkell (talk) 15:06, 16 November 2008 (UTC)[reply]

I think you need two invocations of convert:
convert in.jpg -crop 2050x1475+300+240 - |convert - -draw 'fill black rectangle 1800,0 2050,300' out.jpg
Superm401 - Talk 20:19, 16 November 2008 (UTC)[reply]

Any freeware to rotate a jpeg image n degrees?

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I have some photos where the horizon is not level, and I want to rotate them a few degrees. Can anyone suggest any freeware that can do this please? While a zillion programs can rotate an image 90 degrees etc., I have not found any that can rotate n degrees. I thought Xnview could do this, and it is mentioned in passing in the help file, but after downloading and installing Xnview I have not been able to find out how to get it to do n degree rotations. (Note - losing some of the edge of my image does not matter, loss of quality does not matter) Thanks. 78.151.145.226 (talk) 18:20, 16 November 2008 (UTC)[reply]

I'm pretty sure Paint.NET can do it. It's been a while since I've used it though. Louis Waweru  Talk  18:42, 16 November 2008 (UTC)[reply]

GIMP can definitely do it, but it is a bit daunting for a novice. Having said that if you take the time to learn it you'll be rewarded with a program that can do nearly anything you could ever want. Theresa Knott | token threats 19:45, 16 November 2008 (UTC)[reply]

I would use ImageMagick's convert for something like this:
convert file.jpg -rotate -30 file_rot.jpg
will rotate the file 30 degrees counter-clockwise. Superm401 - Talk 19:57, 16 November 2008 (UTC)[reply]
For this particular job, I'd use GIMP. It is hard to learn (as Theresa noted), but there are MANY tutorials online to get the basics down. The advantage of GIMP for this is that you can use the measure tool to accurately measure how many degrees the picture is tilted and then rotate it specifically that number of degrees. -- kainaw 20:08, 16 November 2008 (UTC)[reply]

Thanks, after some more searching with different keywords I have found that Google's Picasa 2.7 will do n degree tilting, although its difficult to steer it to the particular image you want on your hard drive. I will have a look at ImageMagic. GIMP although doubtless very good would be too complicated for me. Thanks 78.151.145.226 (talk) 21:29, 16 November 2008 (UTC)[reply]

Irfanview! Freeware, small, fast image viewer (with some limited creation/modification capabilities). Dead easy to learn/use and will open just about any image/video format. (Well, bulk image transforms are a little complicated; lots of options.)
And will rotate in degrees. (Even in bulk!) 66.214.189.209 (talk) 23:49, 16 November 2008 (UTC)[reply]
I definitely recommend GIMP - it's not that tough to get into - it's pretty similar to Photoshop - and it's free. Run GIMP, load your image using the usual "File/Open..." - from the little 'toolbox' window it brings up. Then a new window will open with the image inside. Right-click on the image - a drop-down menu will appear - click on 'Layer' then 'Transform...' then 'Arbitary Rotation...'. Slide the 'Angle' slider around - or type in the exact angle you want in the box marked 'Angle'. You can also change the point about which the image will be rotated by click-dragging the black dot in the middle of the image - or by typing numbers into the two boxes in the rotation dialog. When you have it how you like it - click the 'Rotate' button to make the rotation permanent. Now right click on the image again - select 'File' then 'Save...'...and you're done. Easy! SteveBaker (talk) 04:15, 17 November 2008 (UTC)[reply]
One more - PhotoFiltre. You can get an old version for free from http://photofiltre.free.fr/frames_en.htm . It's easier to get into than GIMP and has all the basic features such as colour changing, rotating and filters - and quite a few of them have single-click buttons. AJHW (talk) 12:25, 17 November 2008 (UTC)[reply]

Building Electronics

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So, I got a rather large hub and I stripped it out without damaging anything. I have the circuit board with all the little processor looking things (what are these) on it; I have the power board, and the fan. I also have the guts of a cordless telephone I stripped. Is there anything other than a hub or a phone I can make with these without having to buy many parts? TIA, Ζρς ι'β' ¡hábleme! 19:41, 16 November 2008 (UTC)[reply]

You aren't going to find this helpful, but the simple answer is "No". Modern electronics is very specific and the components you would need to make something simple - like a doorbell or a light flasher - wont be found in a hub or a phone. -- SGBailey (talk) 21:25, 16 November 2008 (UTC)[reply]
Well: Cases, power supplies, fans, switches, speakers, microphones, keypads, LED's, resistors and capacitors, connectors - those are all useful. LCD displays...maybe useful if you can find documentation for them. The actual chips - less so. Most modern consumer devices take all of the small, interesting universal functions and roll them all up into one gigantic custom chip. Even embedded computers tend to have their programs stored in internal ROM memory so you can't reprogram them. Worse still, the documentation on those chips simply isn't available. So you're screwed for sure with the phone chips. Non-consumer products (maybe...MAYBE like your hub) might have used more general purpose devices - you could look at the top of each chip in turn - read off the part numbers (and note any manufacturer logo) and start typing them into Google to see if anything interesting shows up. You may get lucky. The older the hardware you're pulling apart - the better off you'll be. A computer from 20 years ago would be stuffed full of cool stuff. A modern laptop...nothing. SteveBaker (talk) 03:28, 17 November 2008 (UTC)[reply]
I don't think a computer from 20 years ago would be helpful... I had a late 1980s workstation motherboard with zero standard logic devices, all of the logic was either in application-specific integrated circuits or programmable logic array. A minicomputer has lots of usable components, but I wouldn't advise scrapping those since they should be (and many are) in museums. If you want to play around with electronics, use TTLs or 4000 series ICs, they are versatile, easy to use and pretty cheap, around 80 cents each in quantities of 25. Rilak (talk) 09:55, 17 November 2008 (UTC)[reply]
The problem is made more difficult by surface mount components. Those are extremely dificult to solder by hand. (Not impossible, some people with really steady hands can do it freehand, and there are special tools for dealing with surface mount stuff.) APL (talk) 14:18, 19 November 2008 (UTC)[reply]

Free HTML template/gallery software

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Is there any free software that can automate the process of maintaining my website? The tasks I'll need to perform are:

  • Add new images to both the screen and print versions of a page at once, have them reformatted, and in the print version have the row breaks move automatically.
  • Remove images from both versions of a page, and again have the row breaks move in the print version.
  • Update text on both versions of a page, including both "Copies in Stock" and text outside the galleries.
  • Add, remove or edit text, code or styles on multiple pages (which are not versions of the same page) at once. (I don't want to use an external stylesheet, since they sometimes fail to load.)

I may not have access to server-side scripting. I'll be uploading the pages from machines that run Windows XP Professional and on which I don't have admin access; I can't upload them from elsewhere directly, since the server works by mirroring a folder on my network drive. However, I also have a laptop running Kubuntu where I do have root access, and could e-mail or sneakernet files from the laptop to be uploaded. NeonMerlin 20:57, 16 November 2008 (UTC)[reply]

"Page Fault in Nonpaged Area"

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My laptop keeps BSoD'ing for the above reason, which is starting to irritate me since it is actually *functional* for once. What does it mean, and what steps can I take to fix it? -Jéské Couriano (v^_^v) 22:00, 16 November 2008 (UTC)[reply]

This is one of the most common and general BSoD errors. It can mean anything from failing memory to bad antivirus software to a corrupted file system. A quick Google search leads to this MSDN article which gives some troubleshooting advice. « Aaron Rotenberg « Talk « 02:00, 17 November 2008 (UTC)[reply]
Besides that, it may mean that you have some viruses in your system, or you may have that BSOD screensaver thing. Try performing a full hard disk scan using an antivirus, and/or a chkdsk scan; it worked when one of the computers at home crashed with a BSOD on boot. Blake Gripling (talk) 02:18, 17 November 2008 (UTC)[reply]
Most likely, some driver is trying to access an invalid memory location. The BSoD you're getting should display the name of the driver which is causing the page fault. Then do a Google search on the driver and find out what it is - anti-virus/anti-malware software (they install drivers to implement their protection mechanisms), device drivers, even virtual machine drivers. --wj32 t/c 05:51, 17 November 2008 (UTC)[reply]
Could also be bad RAM. I've seen this BSOD a few times in systems with a bad stick. It also may spit out others in that case, but this seems to be the most common. 24.76.161.28 (talk) 10:04, 17 November 2008 (UTC)[reply]
24) Could the following be other BSoD errors associated with bad RAM? "Attempting to write to read-only memory", "Memory Management", "Driver IRQL Not Less Or Equal" -Jéské Couriano (v^_^v) 22:54, 18 November 2008 (UTC)[reply]
Yes to all 3. Especially if you're seeing them all. I personally had a computer that was doing just this after a RAM upgrade; I replaced the stick with another one, problem solved. -- Consumed Crustacean (talk) 16:22, 21 November 2008 (UTC)[reply]
Thanks, Crustacean and to everyone else who answered. -Jéské Couriano (v^_^v) 21:57, 22 November 2008 (UTC)[reply]