Wikipedia:Reference desk/Archives/Computing/2009 February 7

Welcome to the Wikipedia Computing Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.

February 7

Multichannel audio from computer to amp

Hi. I have a rather basic amp that supports Dolby Digital. However, I am unable to get any audio from my computer to turn on the "Dolby Digital" mode of the amp. My sound card configuration has an area which allows one to test "which of the following formats your Digital Receiver is able to decode". It lists DTS Audio, Dolby Digital, and Microsoft WMA Pro Audio. When I test Dolby Digital, I see that my receiver goes into that mode (and that is the only test that succeeds). However, absolutely no media that I have played on my computer has put the receiver into DD mode. Is this because soundtracks are more often in DTS now? Is there some way in software to convert the audio signal for my amp (in real time?)? Does anyone have an example audio/media file they could point me to, encoded in DD5.1, that I could play on my system to confirm that my hardware/software will send the DD5.1 signal when it's available? Thanks...... Birchcliff (talk) 03:08, 7 February 2009 (UTC)

Hi, this is because your digital audio source has to be encoded using DD. There are some DVD's that have only the DD and some only DTs, some have both and some have only 2-channel stereo. I'm sure if you find a DVD that has DD-encoded audio, your DVD playing software (PowerDVD etc.) will send the correct signals to your amp to activate it. Sometimes this can even be forced using a setup function on your DVD content menu. Mass produced DVD players have this via setup functions that force one or the other, and I've even seem some that downsample from DTS to DD if your amp can't handle DTS. Of course, normal computer media such as mp3, wav, etc. are not DD-encoded and as such will only play 2-channel sources using a forced upsampling/emulation of 6 channel sound using software/soundcard setup. Certain divx movies (I think version 6 onwards) support 6 channel encoding, but I think you'd need some fancy AC3/FFD tweaking to actually activate DD on your amp... Sandman30s (talk) 13:35, 8 February 2009 (UTC)

What's the best way to share files between computers?

I'm not sure if what I'm talking about is a server, but I want to be able to have a continuously running computer at home which I can access from e.g. my school, my friend's place or China (I primarily use Linux, so naturally I would like to do this on a Linux OS). An example of what I'd like to do would for example be to be at my girlfriend's place and be able to access my music or movies from her place. If possible I also want to be able to add more files to my computer and changing existing files from afar. I heard you should use something like SSH for this but I know embarrassingly little about that. Can anyone tell me a good place to start? Do I need to pay money for a domain? --BiT (talk) 04:28, 7 February 2009 (UTC)

That's a lot of question wrapped up into a neat little package. Starting from the "client" computer, you first need a way to identify your server (which is an appropriate term here). If your ISP supplies a static IP address then you can just use that ID; if not, you'll probably want to use one of the online dynamic DNS services, which allows your computer to post its current IP address in a known location. So, once you have the "address" of your server, you need to ensure that your messages can get through. If you have a router on your internet connection, you'll need to enable port forwarding of the port that you decide to use (which is related to which software you want to run). Now that you can send messages to your server, you need software on the server to listen for the messages. An ssh daemon is a good choice; ssh encrypts your communications, allows you to open a remote terminal on the server, allows you to ssh tunnel many other services, and has free clients for most any OS. Finally, we can get to the part where you install file sharing software on the server. Samba is a good choice for interfacing with Windows machines—it functions like a Windows "network share". From the client machine, you'll need to open an ssh tunnel for access to the samba service, at which point you will be able to access your shared files. Another option is to set up a VPN (some routers support openVPN with DD-WRT firmware), which, once connected, allows the client to communicate with the server as if they were on the same network segment (allowing, for instance, the use of Samba mentioned above). – 74  05:25, 7 February 2009 (UTC)

Quite a lot of computer jargon you've got there :) even tough I'm rather computer literate I'm still a newbie at all this server stuff so posting some good tutorials or tips on how to do this would be helpful. Before some smarty pants gives me this link, I have looked for "How to make your own server", but didn't find what I was looking for. --BiT (talk) 01:26, 8 February 2009 (UTC)

An easier route might be to set up an SFTP server. --98.217.14.211 (talk) 14:28, 7 February 2009 (UTC)

Easier in what way? --BiT (talk) 01:26, 8 February 2009 (UTC)

I would suggest a portable hard drive. They come in big enough sizes to store all your music and loads of films, and are small enough to fit in your pocket.

I have a lot of portable hard drives and I do store all my music and films on them, but what's the fun in that. ;) --BiT (talk) 01:26, 8 February 2009 (UTC)

The above "jargon-y" post, as you call it, is most of what you want to do. Instead of Samba, you might want to just enable ftpd (the FTP server) on your linux computer at home, and on your router, open up the ports that ftpd is listening on, so you can "get in" from the outside. Note your IP address. It'll be numeric. Then you can FTP to your computer from anywhere and upload or download (or delete...) files. A few bad things about this include (a) your IP address might change at the whim of your ISP. You might not care about this. You could also get clever and write a little daemon that runs continuously on your linux box and uploads its current IP address to Google Docs every hour or something, so you could always check the docs to find out the current IP address. (b) With your FTP ports open it's likely they'll be found by bots, which will try and hack the password. Be clever about your usernames and passwords. Tempshill (talk) 03:45, 8 February 2009 (UTC)

Lets summarize the steps you need to take, and add some links:

1. First off, you want to install a Dynamic DNS client. Otherwise you'd need to know what IP-address your computer has in order to connect to it. Those can change often and are anyways hard to remember. If you use a dynamic dns service, your computer will have a web-address, like "something.no-ip.org" if you use the No-IP service (I've used it in the past and is very happy with it). A guide for setting up No-IP on your computer can be found here (if you use Ubuntu, otherwise google is your friend). It's very easy (the website has changed since the guide was written, but it's still not very hard), and very quick.
2. Now, you need to decide what service you want to use for accessing your files. To keep it simple just for now, lets use ftp. If you use Ubuntu, install the package "vsftpd" (type "sudo apt-get install vsftpd" in the terminal). Now, you will automatically be sharing everything contained in the "/home/ftp" folder.
3. Lastly, you need to forward the correct ports on your router. The ports you should open for ftp are 20 and 21. If you need help with that, let us know.

Now it should work. Go to another computer, type in ftp://[whateveraddressyouhave].no-ip.org (or whatever address your dynamic dns provider gave you) and you should see the contents of the folder /home/ftp.

You might decide that ftp isn't what you want, you want something else. You can try out SSH (which is a way so you can log in to a remote computer), Samba or even just installing a webserver, like Apache (it's much easier to do than you think on Ubuntu). You can easily google tutorials for how to install that stuff (it's essentially just a matter of installing the right package, it usually just works after that), there's plenty of them. If you need anymore help, just come back :) Belisarius (talk) 08:40, 9 February 2009 (UTC)

I'm going to try this :) thanks for the extremely detailed comments, they're almost a complete tutorial. I'll ask again here if I run into any problems. --BiT (talk) 14:50, 10 February 2009 (UTC)

GIMP (zooming into selection)

In Gimp 2.6, is there a way to easily zoom so an area you have selected takes up the whole window. Thanks, 82.32.53.160 (talk) 09:26, 7 February 2009 (UTC)

I don't know of a "zoom in on selected area" tool. It isn't very useful compared to the existing zoom tool (the magnifying glass in the toolbox). Select the magnifying glass. Then, click on the top-left corner of the area you want to zoom. Without letting up from the mouse button, drag a rectangle shape. When you let up off the mouse button, it will zoom in on the area you selected with the magnifying tool. -- kainaw™ 23:19, 7 February 2009 (UTC)

If you hold down CTRL (or was it alt? umm) and move the track wheel on your mouse it will zoom in or out. ---J.S (T/C/WRE) 20:25, 9 February 2009 (UTC)

Desktop Auto-Refresh in Vista

Just since yesterday, my Vista (Home Premium) has stopped displaying new icons and files in the desktop. I have to right-click and refresh every time I make any sort of change. This is a sudden thing, as I have not played around with any settings, nor have I downloaded any new software (besides VLC Player - but this has been happening since before then). Can anyone help out here, and show me how to sort this out (I'll be honest and say I don't want to reboot - only as a LAST resort). TIA. --KageTora (talk) 11:27, 7 February 2009 (UTC)

Why don't you want to reboot? This is the sort of glitch that probably would be fixed on a reboot, it's certainly not a Windows feature (there's a policy that that can hide all icons, but not disable the auto-refresh). However, you could attempt to restart Explorer, the main Windows interface. The easiest way to do this is to logoff and then log back on again, but if that's not an option for some reason you could take the more drastic option to kill it. To do this press Ctrl-Alt-Delete to get up the Task Manager and change to the "Processes" tab. Click "Image Name" to sort them alphabeticallly and right click any copies of explorer.exe and select "End Process". When you have killed them all DON'T close the task manager down, but instead from the File Menu select "File" menu and "New Task / Run". Type in: explorer - This will reload explorer. Some icons from the system tray may not display properly and I really would recommend rebooting as the primary method of seeing if this fixes it. ZX81 ^talk 12:01, 7 February 2009 (UTC)

Database question

I`m interested in starting a database to keep track of my purchases. It is entirely for personal use, which means it would be preferable if I didn`t have to place it online somewhere. I would like to store it on my own HDD and access it directly, via a graphic interface. -- 58.89.206.76 (talk) 13:35, 7 February 2009 (UTC)

How in particular do you intend to use this data? A simple solution would be to track the values in a spreadsheet, but that would limit your ability to do data-mining and report generation (though such data could be imported into a database at a later date). – 74  15:02, 7 February 2009 (UTC)

I agree. A spreadsheet is likely a better option for most operations. If you want to do odd things like find the total of all money spent on lunches at one particular restaurant on Tuesdays, then a db might make sense. If you're using a Windows computer, you likely already have Microsoft Excel as part of the Microsoft Office suite. StuRat (talk) 15:15, 7 February 2009 (UTC)

Even then, a little familiarity with Excel can get that kind of data (I use it for this purpose at tax time all the time—it's easy to say, "sort this by place I spent the money" and then take that smaller subset and say "sort by date"). Personally I think a db would be overkill for such a situation—the opportunity costs in learning how to use it and setting it up far outweigh the small performance benefits in this case. --98.217.14.211 (talk) 15:41, 7 February 2009 (UTC)

If you don't have Microsoft Office (or if you prefer to avoid Excel for some reason), there is a list of spreadsheet programs in the spreadsheet article, including several free alternatives. (The reference desk does not endorse any specific software.) – 74  15:46, 7 February 2009 (UTC)

I sometimes try to use somehting for personal use just so i have the experience of using it. Maybe he wants to do the same thing so he set a simple goal of setting up and maintaining a database just for the sole purpoose of being able to say that he has experience in doing so. To answer your question; Off the top of my head i can only think of OpenOffice as being a free solution, but you can aslo try Microsoft Sql, But i quest it really all depends on your goals. – Elliott  20:10, 7 February 2009 (UTC)

You should use Excel. Microsoft at one point found that a primary use of Excel for most people is "keeping lists of things", which is what I mostly use it for, too. Or you could use the free, inferior equivalent that's part of OpenOffice. Tempshill (talk) 03:34, 8 February 2009 (UTC)

Photoshop layers

The other day, I'm pretty sure I saw a "automatically select layer" option somewhere in Photoshop. It seems I've turned it off, and now can't find it to enable it. Can anyone help? Cheers. Cycle~ (talk) 15:33, 7 February 2009 (UTC)

When you click on the selection tool (or press v), a check box appears in the top panel for automatically selecting layers.--K;;m5m k;;m5m (talk) 17:01, 7 February 2009 (UTC)

Aha! Cheers. It seems I'd turned it on, but wanted it off. That's probably the only place I didn't look – I couldn't think of any search terms (for using the help file) that weren't ridiculously ambiguous. Cycle~ (talk) 18:48, 7 February 2009 (UTC)

Not a problem. Cheers.--K;;m5m k;;m5m (talk) 00:27, 8 February 2009 (UTC)

America's Army

Is it possible to play America's Army offline?--KageTora (talk) 15:52, 7 February 2009 (UTC)

I dont think so, From what i can tell it looks like its an online game. – Elliott  20:02, 7 February 2009 (UTC)

Yes, it seems that way. You spend two hours downloading various files and installing them, and you end up having to play online, anyway.--KageTora (talk) 23:17, 7 February 2009 (UTC)

Those files are for 3d rendering, you download them and install them so that you dont have to download and install them every time you want to play, it makes it easer on the end user(you) and the servers (to try and save on bandwidth) 01:28, 9 February 2009 (UTC) —Preceding unsigned comment added by E smith2000 (talk • contribs)

Mater to Energy conversion (Moved)

Moved to Reference_desk/Science#Mater_to_Energy_conversion

how good is pentium 4 at 3 ghz?

I am thinking of buying a used computer which is a pentium 4 at 3 ghz (with 1 gb of ram). What percentage of the performance could I get of a modern core 2 solo processor? —Preceding unsigned comment added by 82.124.81.87 (talk) 19:42, 7 February 2009 (UTC)

That sounds like my old computer. I use to have an emachine with a pent 4 / 3.06 Ghz with 1 gig of ram. I upgraded to a newer computer running an AMD 4200 / 2.4Ghz dual core with 2 gigs of ram, i did notice an increase in performance but that may be because i also upgraded to a raid 0, a better motherboard, faster networking card, and a much much better video card. I suppose it really depends on what you plan on doing with your computer. – Elliott  19:59, 7 February 2009 (UTC)

It's impossible to answer that question accurately since it will depend on many variables. What app are you talking about? What else are you going to change when you upgrade? Etc. However it is rather likely you will notice a big difference in performance if your app is CPU limited and this is even if your app is not multithreaded. Nil Einne (talk) 05:12, 8 February 2009 (UTC)

For anything short of gaming, graphics design and video editing the P4 3ghz will be an acceptable computer. Stick with XP or linux however. Vista won't be a good experience on a P4. ---J.S (T/C/WRE) 20:22, 9 February 2009 (UTC)

transparent fill in Paint.NET

Resolved

In Paint.NET how do you use the fill tool with transparency? For example removing a white background when pasting an image over another image? —Preceding unsigned comment added by 82.43.88.87 (talk) 22:29, 6 February 2009 (UTC)

I don't know Paint.NET very well but generally you don't fill with transparency; you use something like the magic wand selection tool (which selects based on color, just like Fill tools do), and then you delete the pixels, leaving transparency behind. --98.217.14.211 (talk) 22:42, 7 February 2009 (UTC)

Yes that's exactly what I was looking for, thanks so much

would a pentium 4 era motherboard would have USB 1 or USB 2

I'm thinking of buying a used computer which has a pentium IV 3ghz processor in it. Would that motherboard have a USB 1 or a USB 2 in it? Thanks! —Preceding unsigned comment added by 82.124.81.87 (talk) 21:29, 7 February 2009 (UTC) also - it has 4 memory slots. What do you think the maximum amount of RAM is that it would support? Thanks! —Preceding unsigned comment added by 82.124.81.87 (talk) 21:30, 7 February 2009 (UTC)

We would need to know more about the motherboard or the computer, like a model number or something. But i can tell you that Windows supports a max of 4gigs of ram. If this computer does not have USB 2.0 you can always buy a PCI card that does have USB 2.0– Elliott  21:47, 7 February 2009 (UTC)

Editing conflict :) Regarding the USB 2, probably, but it could go either way. Although USB 2 was out by the time the 3GHz chips came along, that doesn't necessarily mean the manufacturer put it into the computer. You could always add a USB2 PCI card if needed though. For the memory it could be anything from 512Mb to ~4Gb, quite probably around 2Gb. Without knowing the manufacturer/number there's no way to tell, but if you do have those details you can go to Crucial.com and run it through their site (or even better use the memory scanner if you have the actual PC). ZX81 ^talk 21:51, 7 February 2009 (UTC)

Virulent?

My favourite media news site, IGN, and all its affiliates give me a "Warning, this site may harm your computer" message from McAfee (my antivirus program). I use IGN and Rotten Tomatoes for everything, so I was wondering if this warning actually has any merit, as in does anyone else have the same problem? Is IGN actually distributing malware? BeefJeaunt (talk) 21:54, 7 February 2009 (UTC)

Probably not, but their ad servers probably do questionable things with cookies (tracking browsing behavior across sites, for example), which is probably what is setting it off. --98.217.14.211 (talk) 22:55, 7 February 2009 (UTC)

uTorrent Download Location

What is the default download location for uTorrent? I have just downloaded a file, and can't find it anywhere, even after using Explorer to search.--KageTora (talk) 23:51, 7 February 2009 (UTC)

Don't worry. I found it.--KageTora (talk) 23:54, 7 February 2009 (UTC)

it was in the last place you looked, wasn't it —Preceding unsigned comment added by 82.124.81.87 (talk) 00:15, 8 February 2009 (UTC)

Yes, who'd have thought it would be in a folder called 'Downloads'? You'd think it'd be easier than that!--KageTora (talk) 00:30, 8 February 2009 (UTC)