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Wikipedia:Reference desk/Archives/Computing/2007 December 9

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December 9

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svchost.exe

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I am using windows xp. How can I check my svchost has not been hijacked? it seems very busy.. Kittybrewster 02:03, 9 December 2007 (UTC)[reply]

Well, the obvious way is to run a virus and malware scanning program. Have you tried that? --24.147.86.187 (talk) 19:21, 9 December 2007 (UTC)[reply]

Ipod

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Whats the difference between a flash memory nano and a hard drive classic? —Preceding unsigned comment added by 222.154.102.58 (talk) 03:45, 9 December 2007 (UTC)[reply]

The classic iPod uses an actual hard drive with moving parts. It has higher storage, but is more vulnerable to corruption and damage. The flash memory of Nano iPods is lighter and less prone to magnetic damage. The density is less, so it can not hold as much information. However, the technology is rapidly advancing, and flash-based memory is already used in some laptops. Hope this answers your question. 76.99.111.234 (talk) 04:42, 9 December 2007 (UTC)[reply]
I believe that also Flash Memory uses a lot less power than a conventional Hard Drive as the flash memory does not need to 'move'. Don't quote me though :P Tiddly-Tom 10:23, 9 December 2007 (UTC)[reply]

School tracking program

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I heard that some schools are using programs or some way to monitor everything a user does on a network. How is this done? And if possible, are there any popular known programs that do this? Thanks, Valens Impérial Császár 93 04:32, 9 December 2007 (UTC)[reply]

On the internet? That's easy, Squid cache can log everything going through it. --antilivedT | C | G 06:19, 9 December 2007 (UTC)[reply]
Locally? If their code is running on the machines they can see whatever they want --ffroth 23:31, 9 December 2007 (UTC)[reply]
Yeah, my school watches what your doing on your pc. The system is called MyPC or something. When you go up to the main desk and look at the staff PC screens you can actually see hundreds of thumbnail images of all the computer screens they are connected to. So they can see everything your doing but I don't know if they can explorer the computer or just see what you can see at that moment. Hyper Girl (talk) 12:25, 12 December 2007 (UTC)[reply]

Graphics Cards

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Hi, I have this computer with the NVIDIA GeForce 8400 GS TurboCache with PureVideo technology graphics card. Is this sufficient for hi-end games or should I look to change it? Could anyone tell me if the motherboard could take 2 graphics cards as I have an old computer which had 2 graphics cards, I don't know how good but the other computer is but it is not very old and was pretty expensive. Also, I have 3GB of RAM - Do you know if I could stick in another 1GB and if it would be any advantage? (I am running Vista) My old computer was an Evesham Axis Dominator Plus if that helps. I couldn't easily find what graphics cards I had in my old computer, so if anyone knows it would be useful to know even if I could not put them into my new computer. Thanks, Tiddly-Tom 10:20, 9 December 2007 (UTC)[reply]

No 8400GS is a budget graphics card. Having 2 of them won't do you any good either. If you want a computer for gaming you really should be building it yourself. --antilivedT | C | G 10:41, 9 December 2007 (UTC)[reply]
I was not thinking of having two of them - but 2 of whatever is in my old PC which was sold as a gaming PC. Tiddly-Tom 10:46, 9 December 2007 (UTC)[reply]
On my mother board there is room for 4GB of RAM - is it worth taking some out of my old PC which is not used an put it in this one? Also, on my mother board there are:
  • 1x PCI Express 16X.
  • 1x PCI Express 1X.
  • 2x PCI.
I don't know what this means, could I have 2 graphics cards? —Preceding unsigned comment added by Tiddly Tom (talkcontribs) 10:56, 9 December 2007 (UTC)[reply]
The card you have has a pretty recent chipset - but it's the 'budget' version, which generally means it has slower pixel fill rates. Probably, your best bet with this card is to reduce your display resolution when playing games. Adding a second card (using the nVidia 'SLI' approach) will double your pixel fill rate and allow you to run at higher resolutions again. However, polygon rates will probably not improve any. You'd need to use both PCI-Express slots - but notice that one is a 16x slot and the other only 1x - so performance of the card in the second slot will not be good. Personally, I'd just drop my display resolution and wait until the next generation of cards appears sometime next year. But as usual, I have to point out that different games have bottlenecks in different places - if they are CPU-limited, then no amount of messing with the graphics card will help. If it's GPU/vertex limited then buying a higher end card will help, if it's GPU/fill-rate limited then adding a second card will help (and so will reducing display resolution). SteveBaker (talk) 15:13, 9 December 2007 (UTC)[reply]

I wrote a more detailed explanation of games performance on my private Wiki here: http://www.sjbaker.org/wiki/index.php?title=Graphics_cards_and_Games SteveBaker (talk) 17:31, 9 December 2007 (UTC)[reply]

What CPU do you have? If it's halfway decent get a 8800GT and be happy. -Wooty [Woot?] [Spam! Spam! Wonderful spam!] 20:52, 9 December 2007 (UTC)[reply]
Intel Core 2 Quad Q6600 (2.4gHz) - Another question - Do you know if there is a noticeable difference in picture quality between HDMI and DVI? Thank you. Tiddly-Tom 07:09, 10 December 2007 (UTC)[reply]
No difference, believe it or not, except that HDMI carries audio on the same cable, so it may help if you've got a cabling mess back there. -Wooty [Woot?] [Spam! Spam! Wonderful spam!] 10:56, 10 December 2007 (UTC)[reply]
The 8800GT would be a fantastic card to pair with that. It's pretty cheap and is only beaten by the 8800GTX and Ultra. Also if I recall correctly HDMI is just DVI with audio next to it.

WHOIS error

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On a WHOIS what does "ERROR: IP Range Reserved by IANA.org" mean? DuncanHill (talk) 13:43, 9 December 2007 (UTC)[reply]

Some IP blocks haven't been (and some won't ever be) assigned by IANA. So if you whois on 192.168.0.1 (part of a block of non-routable addresses intended for use inside intranets) you get back that the block is assigned to IANA. -- Finlay McWalter | Talk 13:46, 9 December 2007 (UTC)[reply]
I got it when doing a WHOIS for vandal 78.146.191.98. DuncanHill (talk) 13:48, 9 December 2007 (UTC)[reply]
Could it be that the lookup service you used wasn't good at handing non-US registrars? dnsstuff.com is, hands the query off to RIPE, and says the IP is part of a largeish block owned by Opal Telecommunications Plc in Manchester. -- Finlay McWalter | Talk 13:54, 9 December 2007 (UTC)[reply]
OK thanks - I just clicked on the first WHOIS thingy at the bottom of his talk page. DuncanHill (talk) 13:59, 9 December 2007 (UTC)[reply]

The WHOIS link on IP talkpages now goes through Sam Spade.org [1] instead of DNSstuff.com. Apparently, DNSstuff.com changed their business model some months ago. [2]. I'm not sure what this error means, as you can run the same IP through DNSstuff.com age get a valid return. For example; User talk:78.146.191.98 gives the error with Sam Spade [3] bur returns properly with DNSstuff [4]. --— Gadget850 (Ed) talk - 18:18, 9 December 2007 (UTC)[reply]


Pixelating SVG?

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I thought the whole point of SVG images was that they didn't pixelate and look all ugly when you blew them to big sizes. So what's going on here? —Angr If you've written a quality article... 20:55, 9 December 2007 (UTC)[reply]

You're blowing up a rasterized PNG made from the SVG. The actual PNG on the page that the page links to ([5]) is only 1024 pixels wide, but it is being displayed much wider than that. My guess is that there is a hard limit of some sort on the size of the PNGs that Wikipedia's SVG renderer is putting out. In other words, you aren't really blowing the SVG up to a large size: you're rasterizing it (using Wikipedia's internal rasterizer) as a 1024 pixel PNG and then blowing that up to 1500 pixels. --24.147.86.187 (talk) 21:45, 9 December 2007 (UTC)[reply]
Yes - I agree with 24.* but you can download the original SVG and display it in something like Inkscape and you'll get the benefit of zero pixellation. Wikipedia probably caps the size in order to prevent denial-of-service type attacks that you could cause by tying up it's CPU's and memory by demanding a 100,000 x 100,000 pixel display or something. SteveBaker (talk) 23:28, 9 December 2007 (UTC)[reply]
Ok, cool. Thanks for your help. —Angr If you've written a quality article... 05:25, 10 December 2007 (UTC)[reply]
Actually, as far as I can tell, if you go to the Image:USA_Counties.svg page and click on the link just beneath the picture, it actually does send the SVG file to your browser if it thinks you have an SVG-compatible browser (I have Firefox - so it does). This is especially obvious if you bring it up in the Konqueror browser because it draws SVG's V-e-r-y S-l-o-w-l-y so you can be 100% certain that it's not displaying a raster image. Wikipedia appears only to produce the cruddy PNG version for the preview or if it doesn't think your browser can display the SVG version. What puzzles me is why it displays the pixellated version in your sandbox - even though my browser can handle the SVG. Perhaps it's because you forced a particular resolution by telling it you wanted 1500 pixels. Weird. SteveBaker (talk) 00:25, 11 December 2007 (UTC)[reply]
I thought it automatically rasterizes unless you're accessing the actual file directly --ffroth 03:55, 11 December 2007 (UTC)[reply]
Right. It doesn't try to guess which browsers can support SVG natively; Mediawiki outputs it as PNG whenever it displays it on a page. --24.147.86.187 (talk) 18:50, 12 December 2007 (UTC)[reply]

Beep

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I've been trying to make my Java program beep by outputting (char)7, but I don't hear anything. My headphones work fine, since I can listen to music, so I figure it's something in the computer. Any ideas? Black Carrot (talk) 21:53, 9 December 2007 (UTC)[reply]

The BEL character outputs to the internal speaker, not the sound card. Many newer PCs don't have a speaker. --— Gadget850 (Ed) talk - 23:01, 9 December 2007 (UTC)[reply]
Also, it is your terminal emulator that issues the beep when it receives that character. So your terminal emulator may not support it or has it disabled. --Spoon! (talk) 23:06, 9 December 2007 (UTC)[reply]

What should I do to make it beep audibly, then? Black Carrot (talk) 23:11, 9 December 2007 (UTC)[reply]

As Spoon! notes, what a BEL does is up to the terminal emulator. For me (on XP) the Netbeans terminal ignores BEL, but the cmd.exe one beeps. To be fairly portable, use Toolkit.getDefaultToolkit().beep(); instead - that plays whatever the platform thinks an alert sound is (for me, on XP, it's a dull Bonk sound, as set by the sounds applet in the Windows Control Panel). If you want more control than that, you'll need to play a sound clip yourself using javax.sound - see http://java.sun.com/docs/books/tutorial/sound/playing.html -- Finlay McWalter | Talk 23:31, 9 December 2007 (UTC)[reply]
Thanks! That worked perfectly. Black Carrot (talk) 23:49, 9 December 2007 (UTC)[reply]

A non-beep sound would work, too. I'm just trying to get a rough metronome-type thing set up in it. Black Carrot (talk) 23:12, 9 December 2007 (UTC)[reply]

Here's a metronome that plays a WAV file every 1000 ms:
import java.io.*;
import javax.sound.sampled.*;
public class Main {
   public static void main(String[] args) {        
       try {    
           File infile = new File("C:/bip.wav");
           AudioInputStream stream = AudioSystem.getAudioInputStream(infile);
           DataLine.Info mydlinfo = new DataLine.Info(Clip.class, stream.getFormat());
           Clip myclip = (Clip) AudioSystem.getLine(mydlinfo);
           myclip.open(stream);
           for(int x=0; x<20; x++) { // 20 beeps
               myclip.setFramePosition(0);
               myclip.start();
               Thread.sleep(1000); // 1000ms == 1 second
           }
       } 
       catch (Exception e){
           System.out.println(e);
       }
   }
}
I made bip.wav using Audacity's generate function (sine wave, 0.1 seconds duration, 880Hz, amplitude 0.5). -- Finlay McWalter | Talk 00:10, 10 December 2007 (UTC)[reply]
Note, though, that your code only beeps approximately once a second, not exactly. The actual period is likely to be slightly longer, due to the time spent executing the loop, though it could also be shorter if Thread.sleep() was consistently returning early. If you want the average period to be exactly one second, which might be desirable for a metronome to keep it from drifting out of sync, you'd need to make the loop something like:
long nextBeep = System.currentTimeMillis();
for (int x = 0; x < 20; x++) {  // 20 beeps
    myclip.setFramePosition(0);
    myclip.start();
    nextBeep += 1000;  // 1000ms == 1 second
    long delay = nextBeep - System.currentTimeMillis();
    if (delay > 0)
        Thread.sleep(delay);
    else
        nextBeep = System.currentTimeMillis();  // we're late, catch up!
}
You may also wish to catch and do something useful with InterruptedException, e.g. to allow the user to stop the metronome. —Ilmari Karonen (talk) 01:03, 10 December 2007 (UTC)[reply]
THAT TAG IS AWESOME since when has wikipedia had that now?!?! --ffroth 07:42, 10 December 2007 (UTC)[reply]
Tag?? Thanks, Ilmari, that's helped a lot. Black Carrot (talk) 11:40, 10 December 2007 (UTC)[reply]
The source tag --03:56, 11 December 2007 (UTC) —Preceding unsigned comment added by Froth (talkcontribs)

b&

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Is there something on IRC that can tell you which channels you've been banned from? Vitriol (talk) 22:11, 9 December 2007 (UTC)[reply]

No. Change your hostmask to evade bans. Also, nobody says b&, it's called +b --ffroth 23:29, 9 December 2007 (UTC)[reply]

PSP VIDEO PROBLEM

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I have a video that is in, as it says in the properties, MPEG-4 (.mp4) format. It works on my PSP prefectly. I have another video that is in the exact same format as it says in the properties. However, this one isn;t supported by my PSP. I know that there are many different types of MPEG-4 subformats, such as part-14 and part-10, and I am under the understanding that the PSP only suports part-14. Maybe this is the problem, if the 2nd video is in part-10 or something. However, when I go to convert the 2nd video on PSP Video 9, it is not supported there, and it will not convert. What should I do, and why will it not play on my console? —Preceding unsigned comment added by 75.23.77.208 (talk) 23:54, 9 December 2007 (UTC)[reply]

mp4 is a container format. It's likely that the 2nd mp4 contains video in a format that your PSP cannot decompress --ffroth 00:00, 10 December 2007 (UTC)[reply]

How would I fix this? —Preceding unsigned comment added by 75.23.77.208 (talk) 00:02, 10 December 2007 (UTC)[reply]

Re-encode the video from one format to the other. What kind of computer do you have? It will affect what program will be the one you want to use. --24.147.86.187 (talk) 01:10, 10 December 2007 (UTC)[reply]