Wikipedia:Reference desk/Archives/Computing/2008 February 5

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February 5

Does the Wikimedia Foundation only use free sotfware like the Free Software Foundation?

Does Wikimedia only user free software? Does it run Windows. Does it run GNU/Linux? Jet (talk) 01:21, 5 February 2008 (UTC)

MediaWiki says the Wikipedia software is open-source. It's written in PHP, so my guess = Apache+PHP+MySQL. Because the website is huuuge, I think it's on Linux or BSD. —Preceding unsigned comment added by Grawity (talk • contribs) 10:00, 5 February 2008 (UTC)

"The popularity of the Wikimedia projects necessitates the use of many servers, all but two run the GNU/Linux operating system."[1] You can get a list of the exact OSes at the link. Many flavors of GNU/Linux. --24.147.69.31 (talk) 16:58, 5 February 2008 (UTC)

The list at meta:Wikimedia servers shows mostly various types of Linux, although some Solaris and FreeBSD servers are also listed. —Ilmari Karonen (talk) 17:04, 5 February 2008 (UTC)

standard TRS microphones unpowered, need solution

I just made a satisfying purchase lately, or so I thought until I tried to use it. I purchased an Olympus ME15 lavalier microphone, its omnidirectional, comes with a tie-clip, and a 1m cord. The reason why this microphone is so compact is that it relies on a power source through the plug. The TRS connector plug looks that of any old mono TRS microphone plug. Even though the device was built for Olympus' voice recorder products, I thought I could use it as a computer microphone. Why its not working is because the socket in my PC is not providing any power. Is that standard? Was any computer mics that I encountered powered by an internal battery? I hope not, because that would give them a limited lifespan.

My problem is that there are no lapel (lavalier) microphones for PCs or any other audio equipment in stock anywhere (they seem to be loosing favor), And that I'm going to have to make do with this thing. I'm thinking about building a battery "box" that will go between the mic socket and the microphne itself, is that a viable solution? What part of the plug (TRS mono) does the power supply go? How exactly do these microphones get powered? -ANONYMOUS 02:34, 5 February 2008 (UTC)

You'll want to see our phantom power article. Unfortunately, only the last few sentences are completely germane to your question. So please also see electret microphone and its external links.

Atlant (talk) 14:49, 5 February 2008 (UTC)

Im not sure exactly, but I assume alot of computer mics are dynamic to avoid the need for phantom power, or they use such a small charge to pass across the diaphragm, it is less than 48v. As far as I'm aware, phantom cannot be used with a TRS.86.139.90.67 (talk) 17:10, 7 February 2008 (UTC)

Essentially all modern microphones used with low-end electronics (such as computers, cell phones, speakerphones, etc.) are electret microphones; they're the cheapest to integrate into the rest of the electronics and cheap themselves. Dynamic microphones went out with cassette recorders.

Atlant (talk) 01:17, 8 February 2008 (UTC)

irc passwords

i can't remember the password i used when registering an account on irc/freenode. i've searched online for the last 20 minutes trying to figure out how to recover it, but i'm coming up empty handed. i set an email when i registered, and i thought there would be some easy way to have it sent to me. how can i recover my password? StickShaker (talk) 02:42, 5 February 2008 (UTC)

I'd join #support or #help on your IRC network and ask there. Chances are an IRCop will be able to help TheGreatZorko (talk) 12:48, 6 February 2008 (UTC)

Extrapolate a photo's missing piece

Can any existing program automatically paint the missing piece of this wall and continue the falloff of light intensity?

Do any programs exist that will detect lighting gradients and extrapolate them to fill a missing corner in a photo (such as that which occurs when the photo is rotated and cropped) in a more realistic way than could be done with rubber stamping, at least if the cut-off object is something smooth and flat like a wall? NeonMerlin 02:53, 5 February 2008 (UTC)

Personally I'd probably just draw a gradient in by hand (with Photoshop or the line) on a layer below and try to get it to match up fairly well. Then you can run some filters on it to roughen it up a little bit. As for a program that will do it automatically, and correctly, I suspect not. --24.147.69.31 (talk) 16:14, 5 February 2008 (UTC)

If you find some, let me know. It's one of the features I really wish Resynthesizer had. I suppose it might be possible to achieve something like it with a combination of Resynthesizer, manual gradient fitting and the grain extract/merge layer modes: first fit a gradient as closely as possible to the existing lighting, then extract the difference (which would hopefully be mostly high-frequency texture) and use Resynthesizer to fill in the missing area. —Ilmari Karonen (talk) 17:40, 5 February 2008 (UTC)

Batch red eye removal

What Linux apps can remove red eye from photos as a batch operation? NeonMerlin 05:34, 5 February 2008 (UTC)

GIMP has batch processing and a basic red-eye removal tool. The trick is that red-eye removal will remove a specific shade of red, turning it black. Since you won't manually be pointing out where the red is on the photo (in batch mode, you have to do the whole photo), any red of that particular shade will be turned black. That can cause problems. -- kainaw™ 13:38, 5 February 2008 (UTC)

How do you set up a task force on a different MediaWiki?

I'm trying to set up a task force at my own Wiki. Can some one click on this link and help me? --75.181.81.73 (talk) 11:05, 2 February 2008 (UTC)

I can see that 75.181.81.73 has been active on Wikipedia for only a few days, and certainly do not want to bite the newbies. To me however, the question as stated violates the guideline Wikipedia:Spam, please correct me if I'm wrong. Perhaps it would be better for the original questioner to reword the question: "How does one attract attention to a personal wiki project? The project in question deals with modern visual culture, the plots and their charactes." --NorwegianBlue ^talk 11:36, 2 February 2008 (UTC)

Try failing over at digg, someone might be interested :D\=< (talk) 12:29, 2 February 2008 (UTC)

I've been active longer than that, I was just not logged in. It's not spam. Did you not check out the link? I'm asking how do I set up a task force on my Wiki. I followed the steps on Wikipedia, but I'm missing something. --MahaPanta (talk) 18:00, 2 February 2008 (UTC)

My apologies. I did follow the link, as my paraphrasing of the introductory sentence of the main page should indicate. The link led to a page with the title "MVC:WikiProject San-X/Omusubiya-san task force", an image, and the text "{{subst:MVC:WikiProject San-X/Coordinators/Toolbox/Task force boilerplate|Omusubiya-san task force|OnigiriTF}}". I take it, then, that your question is why the template is not expanded. I have only limited experience in setting up my own wiki, but I suspect that the reason is that some required template is not defined. For example, when you type "Template:Task_force" in the search box of Wikipedia, you are taken to a template called "Task force". When you type "Template:Task_force" in the search box of your wiki, you are offered to create a new page. Hopefully, someone more knowledgeable in the inner workings of Wikipedia and MediaWiki software will come along and give you a better answer. Best of luck with your project. --NorwegianBlue ^talk 20:24, 2 February 2008 (UTC)

Thank you. Since we got that misunderstanding out of the way, you were able to at least point me in the right direction. I'm going to try coping that template over since I'm using the same MediaWiki code that Wikipedia uses. --MahaPanta (talk) 20:41, 2 February 2008 (UTC)

Does anyone know? --75.181.81.73 (talk) 07:15, 3 February 2008 (UTC)

The problem you are having is to do with namespaces on the wiki. You're naming stuff "MVC:...", while the project namespace is "MVC Wiki:...". There are two solutions I can think of: change the name of the project namespace to "MVC", or rename the files to start with "MVC Wiki".

• If you have access to the server the wiki is hosted on, you can rename the "MVC Wiki:" namespace to "MVC:" by editing LocalSettings.php, adding the following on its own line to the bottom of the file:

$wgMetaNamespace = "MVC";

Note the semicolon (;) at the end of the line. You could also enable subpages at the same time:

$wgNamespacesWithSubpages[NS_PROJECT] = true;

See $wgMetaNamespace and $wgNamespacesWithSubpages

• Otherwise, rename (move) the project from MVC:WikiProject_San-X/... to MVC Wiki:WikiProject_San-X/...

Then create the page MVC_Wiki:WikiProject_San-X/Coordinators/Toolbox/Task_force_boilerplate (or MVC:WikiProject_San-X/Coordinators/Toolbox/Task_force_boilerplate if you renamed the namespace). You can then {{subst:...}} this into any pages.

As an aside, there is a third, subtle trick you can use. When using templates, MediaWiki will look in the "Template:" namespace (eg using the {{X1}} template takes you to Template:X1). But you can force templates to look in the main (article) namespace by prefixing it with a colon (eg {{:Main Page}}). As the MVC: pages are currently in the main namespace (as they're not in the "MVC Wiki:" namespace), you can also access them by using {{:MVC:Whatever}}. For subst, this would be {{subst::MVC:Whatever}} (note the two colons). --h2g2bob (talk) 17:13, 3 February 2008 (UTC)

I added

$wgMetaNamespace = "MVC";

$wgNamespacesWithSubpages[NS_PROJECT] = true;

to the local settings, but it's sill not working. --75.181.81.73 (talk) 22:32, 3 February 2008 (UTC)

Graphics card heat

Using nTune I decided to check out the temperature of my video card today. It's a XFX GeForce 6800GS. It was idling at 72 degrees Celsius, which is pretty hot for just idling. I turned on Half-Life 2 for a few minutes and I got it to top out at 116 degrees Celsius (that's 239 degrees Fahrenheit!). The game was locking up every few seconds. Should I be looking into a new card, a new fan, or water cooling? Useight (talk) 07:02, 5 February 2008 (UTC)

I suggest you to check the specifications of your graphics card manual or in internet. Since that is the place where you get the results for benchmarks upon performance, quality, etc. In each card's reviews, they will mention the temperature of the card's idle state and at maximum usage. so check out that and you will know the thershold at which your card should fall in. Then think about replacing. Coz your fan could be a problem after-all —Preceding unsigned comment added byBalan rajan (talk • contribs) 09:01, 5 February 2008 (UTC)

[2] under the "Is the newborn hot?" section states that their XFX 6800GS card idles at around 40-45 deg. C, and peaks at 65 deg. C under full load. Some of the heat could also be attributed to case temperature, which is partly dependent upon ambient temperature and case cooling. My opinion is that your card is running at abnormally high temperatures. It's most likely that your Graphics card fan is malfunctioning and/or poor contact between GFX card heatsink and GPU. I'd suggest you take a look at your GPU Fan first, and check that it's actually working before trying anything drastic. Also, is your GPU overclocked? That is also another possible cause for high temps. Tetsuox (talk) 09:50, 5 February 2008 (UTC)

My 6600GT runs at 60 degrees idle with compiz, and goes up to nearly 100 while playing TF2, and it's still here after 3 years. Not overclocked, I think I need a bigger fan on there or something... But I think your case is too high, check that the heatsink is actually touching the chip (look at it sideways/top down, see if you can see any gaps between the chip and the heatsink) and your fan is on. Also try touching the heatsink to see if it's actually hot. --antilived^{T | C | G} 10:22, 5 February 2008 (UTC)

My card came factory overclocked a little by XFX, but I didn't overclock it at all. I'm going to get a can of compressed air and try to clean out my PC a little and move up in expenses from there. Useight (talk) 15:52, 5 February 2008 (UTC)

One more thing to try is running your computer for a while with the side of the case open. If that makes the temperature go down, your case has inadequate (or inappropriately installed) ventilation. —Ilmari Karonen (talk) 16:57, 5 February 2008 (UTC)

threads in computerscience

can we use assembly language or high level language in making a thread? also can we possibly write our own thread for kernel mode?Jasunand (talk) 07:30, 5 February 2008 (UTC)jasunand

If the Operating System supports threads, then assembly language will allow you to program threads (with extreme difficulty). Not all high level languages have syntax for programming threads, but I doubt you'll be using one that doesn't support it. If you are writing a kernel mod, it is possible (and common) to use threads. -- kainaw™ 16:02, 5 February 2008 (UTC)

threads (2nd question)

are user threads supported by operating ystem?Jasunand (talk) 07:41, 5 February 2008 (UTC)

If you mean multi-threading in user mode, then yes (on Windows, at least). --grawity ^{talk / PGP} 10:01, 5 February 2008 (UTC)

Check out our article Thread (computer science) to answer your general questions, and let us know if there's anything you don't understand. --Sean 17:37, 5 February 2008 (UTC)

Jasunand, do you really mean "user thread", rather than just "thread for userspace program"? If so, take a look at our fiber (computer science) and green threads articles. User threads aren't implemented using support from the OS - they instead perform basic cooperative multitasking using solely userspace code (that is, they don't make syscalls and aren't managed individually by the system scheduler). -- Finlay McWalter | Talk 21:39, 5 February 2008 (UTC)

Is Google AdSense Completely LEGAL and safe?

As in, I want to avoid Click-frauds, and on the whole, have a good AdSense experience. Please help me out. Thank you so much! —Preceding unsigned comment added by 122.169.41.253 (talk) 08:20, 5 February 2008 (UTC)

See Google Adsense and clickfraud for more. Adsense is safe as long as you don't use it ;) --Ouro (blah blah) 08:27, 5 February 2008 (UTC)

how to check out timings for executing a function in VB

Hi everybody, I'm working in Visual Basic 6.0. In VB's inbuilt function, is there any way to calculate the time that each function for eg (INSTR, MID etc) may take so that my program can be executed as fast as could. Because of this, my program runs slower and I'm unaware of how much time that each function takes. Could you please suggest me any links that may explain about the timings in VB instructions?...Thanks —Preceding unsigned comment added by 122.164.48.124 (talk) 08:55, 5 February 2008 (UTC)

There's no in-built way that I know of to break down execution time by function, other than putting start and stop timers before and after everything and doing it manually. There's no automatic way to optimize code; you've got to go through and figure out what's cause the slowdown. INSTR and MID by themselves shouldn't be slowing things down in a major way. If you are running lots of loops, try to make sure that you aren't doing anything in a loop that you don't need to do right there, and aren't calculating anything on the fly that you couldn't calculate ahead of time (e.g. if you had a program that needed the value 2*PI a lot, just calculate it once and store it in a variable, don't force the processor to re-calculate it every loop). If you posted the troublesome code here I'm sure we could take a look at it. --24.147.69.31 (talk) 15:40, 5 February 2008 (UTC)

You want a piece of software called a profiler. Googling for Visual Basic profiler indicates that various ones are available. --Sean 17:34, 5 February 2008 (UTC)

Thanks for your suggestion . I am concat the string in loop and save in a variable. The length of string is going to large so time takes to handle the string. So what can I do Please help me —Preceding unsigned comment added by 122.164.48.124 (talk) 10:57, 6 February 2008 (UTC)

When I first saw this discussion, I suspected that string concatenation might be causing the slowdown. Two possible solutions:

• use a fast string class - Google "VB6 string class" for lots of samples
• allocate a large-enough array at the start of the loop, add each piece of the string to it, and use the join function to make it into the final string (this is effectively what the fast string class will be doing).

(It's no help to you here, but in VB.NET you could use a StringBuilder object.) AndrewWTaylor (talk) 12:31, 6 February 2008 (UTC)

Yeah, concatenation can be slow. I'd do what AndrewWTaylor says and put off the final concatenation until the end, give that a shot. You might also test out other ways to accomplish the same thing, like outputting it all directly to a temp file and then reading that back in (no clue if that would be faster, but might be worth a shot). --98.217.18.109 (talk) 03:23, 8 February 2008 (UTC)

How do you convert an EPS into an SVG?

Hi! How do you convert an Encapsulated PostScript (EPS) into an Scalable Vector Graphics (SVG)? --escondites 16:24, 5 February 2008 (UTC)

Try using OpenOffice.org Draw, I believe it can do that, though I wouldn't expect the results to be very pretty (I find that Draw's SVGs often don't work well at all in other SVG editing programs, like Inkscape). --24.147.69.31 (talk) 16:43, 5 February 2008 (UTC)

Inkscape can import EPS files, sometimes even successfully. I believe it uses pstoedit for the actual conversion. —Ilmari Karonen (talk) 16:50, 5 February 2008 (UTC)

I tried pstoedit yesterday and couldn't squeeze what I wanted out of it, but for a different conversion though. --Ouro (blah blah) 13:19, 6 February 2008 (UTC)

I just tried Ghostscript combined with GSview, it worked perfectly! --escondites 14:35, 6 February 2008 (UTC)

Since my first reply above, I've also found out that Scribus can do an excellent job of importing PostScript files and exporting them as SVG. Based on the few files I've tried it on so far, it's working much better than pstoedit ever did for me. —Ilmari Karonen (talk) 02:05, 11 February 2008 (UTC)

Good NNTP servers

Are there any good NNTP servers? ("good" includes being free of charge) --grawity ^{talk / PGP} 16:27, 5 February 2008 (UTC)

Who would give you a good service for free? Who is going to pay for terabytes of storage, servers, high-speed networks and support? Anyway, giganews (tier 1) is excellent for a decent cost IMO. Sandman30s (talk) 10:02, 6 February 2008 (UTC)

I'd recommend NewsHosting over Giganews, they are cheaper (from what I remember - neither site can be viewed on my current network) and have some other small things better than Giganews TheGreatZorko (talk) 12:47, 6 February 2008 (UTC)

Gee, I thought the answer was gonna be something like INN. --tcsetattr (talk / contribs) 21:32, 6 February 2008 (UTC)

Super Bowl Introduction Video

Right before the Super Bowl was an introduction video. It featured such scenes as The School of Athens and Martin Luther King Jr. in relief, and a television in an art gallery. I can't find the video to watch or save to my computer again, I'd like to have it. Any help? Mac Davis (talk) 18:20, 5 February 2008 (UTC)

Anything related to the Super Bowl is the property of the National Football League. And as they said during the game, "reproduction and distribution of any material (including the broadcast) is Illegal". I don't think you'll find help here, since most Wikipedia users are strict when it comes to what is free and what is not. — Kjammer  ⌂ 23:57, 5 February 2008 (UTC)

That's why I usually record the Superbowl while it's playing. Then I can get commercials, highlights, or whatever. This year, though, my TV tuner card for my computer was broken, so I didn't record it. Sorry. Try YouTube, Google Video, or something I do not endorse, a BitTorrent. Useight (talk) 01:46, 6 February 2008 (UTC)

MSN live messenger

hello,

iv asked this sort of question a few days ago but here we go again:

• i have windows XP normal edition thingy
• i had windows live messenger
• i deleated it using add/remove programs (i cant remember why)
• now i want to re-install it back onto my computer
• BUT when ive been onto the MS live website, clicked download and stuff....when it comes to installing it and the special windows live bok comes up it:

1. scanning/checking your computer for live products [there arent any!]
2. windows cant install this product
3. get help with this problem/try again later

This has been happening for about 2 weeks now and very annoying....

1. how do i fix the problem?
2. (are there similar messageing programs that will allow me to communicate with friends using windows live meaaenger?)

thanks, --The world tour (talk) 18:52, 5 February 2008 (UTC)

Pidgin (software) will do MSN IM. -- kainaw™ 19:02, 5 February 2008 (UTC)

DRM and Media Converter

I am about to (shame on me!) purchase this album, with these restrictions. I guess they come in MP3 format; if I were to convert them to WAVs and then back to MP3s using the above program, would the DRM protection be gone? Obviously I take full legal responsibility :D Porcupine (prickle me! · contribs · status) 19:19, 5 February 2008 (UTC)

Neither MP3 nor WAV format supports DRM. To be DRMed, they must be WMA (Windows Media) or M4A (iTunes).

"Obviously I take full legal responsibility" Yeah, sure you will.

Also, the "Usage rights" contains the line:

"CD Burning 10 The number of times this item may be burned to a CD"

So you can burn the song(s) to CD and rip them into a clean MP3 (or AAC or OGG or FLAC or WHATEVR).

--grawity ^{talk / PGP} 19:23, 5 February 2008 (UTC)

...but since the list says "Format: MP3", I have absolutely no idea how the restrictions will be enforced.

A tip: if the site requires some weird software to play your songs, don't install it until you r ead the license. --grawity ^{talk / PGP} 19:26, 5 February 2008 (UTC)

Right... I'll look into it. Would it really work to just burn and rip them, if they were DRMed? Would my original idea of converting to WAV/OGG or something and then back also work (being less CD-intensive :D)?Porcupine (prickle me! · contribs · status) 19:34, 5 February 2008 (UTC)

1. Once you burn a song into a CD (Audio CD, to be more exact), it's in pure plain CD-Audio format, and you can then rip the song back into any format you want. (And I don't think a CD-R would be that expensive.)

2. If you convert a song to a DRM-free format (WAV, MP3, OGG, FLAC), it loses any DRM. --grawity ^{talk / PGP} 19:40, 5 February 2008 (UTC)

OK, last queries here... first, when I download the music, will I get a license with it too, a "tangible" file, or is the protection in-built into the tracks (ignoring the MP3 issue, of course)? And secondly: why do people bother protecting files when they can easily be stripped of the DRM? It sounds silly! Porcupine (prickle me! · contribs · status) 19:43, 5 February 2008 (UTC)

1. If the file format supports DRM (examples are Windows Media WMV and iTunes M4A), then the file will be encrypted by the program and the key will be saved in your computer, and if the player finds the key + knows the algorithm, then the file is decrypted and played|burned. (You might want to read article on DRM.)

If the format doesn't support DRM, then it's just a file.

2. No idea why they do so. Maybe to make it harder? But even Sony (IIRC) suggests you to burn the song to CD and rip it if you want to use alternative players (Winamp, foobar2000, others). --grawity ^{talk / PGP} 20:02, 5 February 2008 (UTC)

Thanks for all your help - it's downloading now!! Porcupine (prickle me! · contribs · status) 20:09, 5 February 2008 (UTC)

Converting a file to WAV and then to MP3 does a lot more than "strip the DRM". You have a compressed version of the song to begin with, whether WMA or M4A. Whatever program you use to make a WAV file from that will necessarily have to "guess" at what the missing bits are. Then you will apply another round of compression to the WAV file, losing other bits. This is analogous to a document that has been photocopied several times; maybe you can still read the words, but it won't be the crisp clean text that was first produced. Depending on the type of music you are listening too and your own personal preferences, you might not hear or care about the results, but don't think you are getting an exact copy. --LarryMac | Talk 20:15, 5 February 2008 (UTC)

You're right - the difference was very noticeable! Would the CD-burning trick lose quality? Porcupine (prickle me! · contribs · status) 20:33, 5 February 2008 (UTC)

Yes, unfortunately, that is essentially the same process - compress/uncompress/compress. --LarryMac | Talk 20:38, 5 February 2008 (UTC)

Is there any lossless way to do it? And, having done these processes, is there any way I can check the DRM presence or not? --Porcupine (prickle me! · contribs · status) 20:41, 5 February 2008 (UTC)

Maybe I'm being terribly naive in this day and age, but are you sure these aren't simply legal restrictions without technological enforcement? I see nothing on the two pages you linked that directly suggests that they're using DRM. You haven't mentioned yet the file type of the songs you downloaded. If it's MP3, and you're using an ordinary MP3 player (not a special one they made you download), then as far as I can see there can't be any DRM involved. -- BenRG (talk) 21:10, 5 February 2008 (UTC)

They're MP3 files and I'm using WMP - is it true that MP3s cannot be DRMed? Porcupine (prickle me! · contribs · status) 21:27, 5 February 2008 (UTC)

That is correct. See Comparison of audio codecs. I can't access the site you first referenced, but I think BenRG may be correct. --LarryMac | Talk 21:41, 5 February 2008 (UTC)

Best part is, if it's unencrypted you can burn it to as many CDs as you want since there's no DMCA with its iron boot pressing down on your neck. IANAL but I seriously doubt they can just attach arbitrary conditions to mp3 files and expect them to be legally binding --:D\=< (talk) 23:50, 5 February 2008 (UTC)

The reality is that no files can be DRMed. MP3s just take out the middle man. --Sean 00:14, 6 February 2008 (UTC)

Ehhhhh what. Files can be DRMed (with varying degrees of effectiveness- microsoft's throwing hundreds of programmers at constantly changing the algorithm and pushing it with windows updates has made WMA digitally uncrackable iirc. And MP3 definitely don't plug the analog hole- why would you use analog if it's completely open anyway :D\=< (talk) 12:41, 6 February 2008 (UTC)

My point was that all DRM schemes fall down in the real world due to the analog hole, among other reasons. Throwing hundreds of programmers at that won't change it. --Sean 00:10, 7 February 2008 (UTC)