Wikipedia:Reference desk/Archives/Computing/2013 September 1

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September 1

Resetting modem and wireless router

Resetting my modem and wireless router seems to clear up internet connectivity problems a good 95-99% of the time -- my question is how and why, if anyone happens to know off-hand. What the mechanism is. Thanks. Vranak (talk) 00:38, 1 September 2013 (UTC)

Perhaps you get a new IP address. Perhaps a bug has resulted in an inconsistent state between your modem and the other end of the connection. Resetting will start that off again, and normally it should work for a while before a bug strikes again. Graeme Bartlett (talk) 11:10, 1 September 2013 (UTC)

Interesting. Do you know of any way that I might diagnose or fix such a bug? This has been a chronic problem for years and it never occurred to me that it might be permanently fixable. Vranak (talk) 19:45, 1 September 2013 (UTC)

I can only speak for one particular router I used to own, but I used to have to restart it due to the Routing table filling up and not clearing correctly, for some reason. This was listed as an issue with the particular modem, I didn't work it out for myself. The solution for me was to get a new router. Now, if you have a modem AND a wireless router, you can do some troubleshooting to work out if it is one device or both playing up. First thing I would do is plug a computer directly into the router so that you are connected to LAN rather then WLAN port. WLAN would probably be the most common cause of problems. Wait until you are having internet issues and try the LAN connection, if it also has issues, you rule out WLAN as the cause. Then, see if you can connect a computer directly into your modem, wait until you have problems and see if the computer connected directly to the modem is affected. That way you can rule out the router. But I suspect the modem is probably the least likely culprit. These days, you can get pretty good modem wireless routers in one device, whether you are on cable or ADSL, that's what I've got and I don't remember restarting my router since i plugged it in probably a year ago. Vespine (talk) 00:06, 3 September 2013 (UTC)

There is a chance that the modem vendor could have a new microcode for your box on their web site, so you should take a look. However in many cases they will have moved on to a new product and will no longer support the old unit. You may be able to view the status of things on the modem by way of a web page, or SNMP requests (which will need more software to exploit). However any bug may not be immediately evident, but you may see counters not increasing when you expect. Without having access to what the ISP thinks is going on for your device you are partly blinded. You could work your way up through the network layers to try to figure out what is broken. But the effort to professionally debug your issue probably costs more than buying a new device. Graeme Bartlett (talk) 09:12, 4 September 2013 (UTC)

Java library for animated SVG graphics

I need a java library that can view with animated SVG graphics. More specifically, it needs to be able to tell what color a given point has at a given time. I also need some instruction on how to download the necessary libraries onto Eclipse.

I need a program that can make animated SVG files.

Any suggestions? — DanielLC 03:14, 1 September 2013 (UTC)

Batik is the leading SVG library for Java. It supports rendering SVGs into a Java2D Graphics contexts, which would allow you to sample pixels. It supports animation done in JavaScript by using Rhino; I don't know about its support for CSS and SMIL animation. Batik also supports creating SVGs. You should probably ask on the Batik list about specifics, and how to set Eclipse up for it. -- Finlay McWalterჷTalk 11:59, 1 September 2013 (UTC)

Do you have to render an entire frame to get one pixel? I am making an entire image each frame, albeit one without regularly spaced pixels, or even pixels that appear at the same time in the animation. I'm trying to show relativistic effects. I suppose it might be possible to get it to work if I offset the image and only ask for a 1 by 1 image, as long as anti-aliasing doesn't get in the way. — DanielLC 21:13, 1 September 2013 (UTC)

If all you want to do is to get pixel color at x,y coordinates you may not need a library, but implementing an algorithm that yields the result will still be lengthy. 190.60.93.218 (talk) 15:00, 3 September 2013 (UTC)

What to do with hard drive strike?

In trying to find an article about read heads striking a hard drive, I searched for hard drive strike and found both Head crash and Click of death. I'd like to make hard drive strike a bluelink, but what is best?

• Redirect to head crash, since the term normally means that
• Redirect to click of death, since the term normally means that
• Make a disambiguation page, since the term can often mean either one
• Make it a bluelink that does something else
• Leave a redlink, because it's not a plausible search term

I think we can here ignore the "We don't answer requests for opinions, predictions or debate" bit, because I'm basically asking for information on what's most commonly meant by "hard drive strike". Nyttend (talk) 04:31, 1 September 2013 (UTC)

I'm not familiar with the term, and google returns nothing useful for it. Maybe nothing is commonly meant by it. Do you have a link you can provide where it is used? RudolfRed (talk) 05:24, 1 September 2013 (UTC)

No. When trying to find an article about the concept, my first thought was "hard drive strike", analogous to "prop strike" in aircraft, when the propellor hits the ground. I have no clue how many other people use it; that's why I offered "leave a redlink" as an option. Nyttend (talk) 17:31, 1 September 2013 (UTC)

While it seems to me this question is better addressed elsewhere, I'm with RudolfRed here. I've never heard the term used before despite being well aware of head crashes and if there's no results for it I don't think we should make a redirect. Redirects are cheap and I support many redirects for spelling etc but I also think we shouldn't redirect if it's going to confuse which means unless it's obvious there should be some mention of the term. And despite the connection to 'prop strike' I don't think this is obvious enough (head strike perhaps). Nil Einne (talk) 13:05, 4 September 2013 (UTC)

I would rather redirect it to the more general term Hard disk failure, if we make a redirect at all. That would cover both the head crash and the click of death. - ¡Ouch! (^{hurt me} / _{more pain}) 06:10, 5 September 2013 (UTC)

Hard disk drive failure actually; Hard disk failure is another redirect.

Resizing (cutting down) screen protectors

I purchased 3 really cheap, as in heavily discounted, iPod screen protectors. I want to know if it is practical to cut them down to fit smaller screens, like a Digital camera, Blackberry or Mp3 player. As they are so cheap it doesn't matter if it doesn't work, or if I have to experiment & waste one. Anyone tried this or have any suggestions? --220 of ^Borg 05:13, 1 September 2013 (UTC)

I've done that before without issue; there's nothing special about the edge of a screen protector. Naturally it's much easier to cut it while it's still on the backing material. -- Finlay McWalterჷTalk 11:45, 1 September 2013 (UTC)

For sure - you shouldn't run into any problems. It's basically like cutting a large piece of glass to fit a smaller window. --.Yellow1996.^(ЬMИED¡) 17:42, 1 September 2013 (UTC)

Good to know that it's possible and can be done, though. But that's what I mostly expected. Thanks Finlay and Yellow. I think I paid about A$1.40! 220 of ^Borg 19:02, 1 September 2013 (UTC)

So much? Nil Einne (talk) 20:08, 1 September 2013 (UTC)

If they're Apple-official screen protectors, then I bet that's more than a bargain! --.Yellow1996.^(ЬMИED¡) 01:30, 2 September 2013 (UTC)

Let's not vilify Apple too much now. I recently saw the price for two screen protectors for an HTC Rhyme and the price was something like US$12. Dismas|^(talk) 01:33, 2 September 2013 (UTC)

Screen protectors are like printer cables. If you buy them at the same time as the phone you're going to pay a ridiculous price for them, but if you buy them at a place that doesn't sell phones you'll only pay a couple bucks. APL (talk) 13:46, 3 September 2013 (UTC)

Not 'Apple-official' Yellow1996. i'Coustic brand Part № IC097 for 5th Gen Ipod Touch(2012). On 'clearance' at Targét. There are generic protectors available, and they are 'cut to size', harking back to my original enquiry.--220 of ^Borg 20:29, 3 September 2013 (UTC)

Ah - thanks for the clarification. But now I'm curious as to how much Official Apple screen protectors cost... ;) --.Yellow1996.^(ЬMИED¡) 01:03, 4 September 2013 (UTC)

Guess- more than anyone else's, and if they're nearly the same size as Apples' they'll start litigating! :-D --220 of ^Borg 12:38, 4 September 2013 (UTC)

Are they're bought from a large retail store in which case I guess the price isn't too bad. I bought 3 or 5 from eBay for one or two US cents once, to be fair this was an auction one of the ones some sellers sell to get or improve their feedback so you may have to bid a few different times before you win which may be too annoying for many but when I looked you could get 5 for US$1.00 (probably less, this was the cheapest I noticed per quantity although you could also spend AUD1.00 for 3). Of course you have to wait for it to arrive from HK/China but it shouldn't take that long in Australia. Nil Einne (talk) 13:20, 4 September 2013 (UTC)

CAD$24.95 for one. --.Yellow1996.^(ЬMИED¡) 15:28, 4 September 2013 (UTC)

python sockets

i'm somewhat new to network programing, but i have a fair amount of experience programing in python, as well as protocols. in the socket module, i was wondering what the "setsockopt" method for socket objects does. thanks, 70.114.248.114 (talk) 09:03, 1 September 2013 (UTC)

If you are on any kind of UNIX, type man setsockopt into the shell. If not, try Googling "man setsockopt" - it will bring up a UNIX (or Linux) manual page among the first hits. Setsockopt is a UNIX system call that allows the setting of various socket options. It e.g. allows address reuse (so that multiple processes can get a UDP data stream), linger time (how long TCP will wait before it releases the socket), enables broadcast, and so on. Many of the functions in the Python OS and network related modules are simply thin wrappers around the underlying UNIX/Posix system calls. --Stephan Schulz (talk) 09:19, 1 September 2013 (UTC)

Windows' Winsock library, which underlies Python's socket library on Windows, roughly apes the same Berkeley sockets library from which modern POSIX sockets descend. So, broadly, socket.setsockopt works on Windows much as it does on Linux. Microsoft's documentation for the native setsockopt is here. -- Finlay McWalterჷTalk 10:39, 1 September 2013 (UTC)

Telephone numbers

If phone companies reuse numbers, does that mean if someone changed their number due to unwanted advertisement calls or text, the person the number was reassigned to would continue to receive these? Clover345 (talk) 17:26, 1 September 2013 (UTC)

If the number was on someone's robocall list, then I guess they probably would continue to get the unwanted advertisements. If it was an actual person they might stop if they found out the number had changed owners... though maybe not. --.Yellow1996.^(ЬMИED¡) 17:45, 1 September 2013 (UTC)

Yes, for instance there are multiple threads on Vodafone's customer forums about this very issue. A lot of providers hold off on recycling numbers for at least six months to try to prevent this but that won't prevent any persistant callers with out of date records. Nanonic (talk) 19:39, 1 September 2013 (UTC)

This is solely a matter of demand for numbers. Carriers don't want you calling up complaining you are getting wrong numbers, it wastes your time and theirs. New York Telephone, back before it was part of Verizon, would standardly keep phone numbers out of circulation for a minimum of one year. Once they were required to "share" their network with other "carriers" that went down to 3 months, then one month in a lot of cases. μηδείς (talk) 22:00, 1 September 2013 (UTC)

It happened to me. I got the number from a bankrupt home construction company, and would keep getting calls like this: "You installed a deck for us ten years ago, but now it needs repairs". To add insult to injury, the phone company tried to make me pay for their $500 full-page yellow pages ad. StuRat (talk) 00:29, 2 September 2013 (UTC)

computers

how do I safely remove everything from my computer and only put back the things I want? — Preceding unsigned comment added by 108.74.164.239 (talk) 19:28, 1 September 2013 (UTC)

Are you referring to the hardware or the software? And could you be more detailed in what you're trying to achieve? Dismas|^(talk) 19:47, 1 September 2013 (UTC)

I assume they mean software. First I'd back everything up to an external USB hard drive. (Around $100, depending on the size, if you don't already have one.) You can then re-install the operating system, and all the updates for it, which will wipe the install hard drive clean (although not clean enough if you are worried about bad guys getting ahold of it, in which case more severe actions are required). You can manually re-initialize any other hard disk (except for the external hard disk containing your backup, of course.) Any data (songs, photos, text files) can then be copied back directly, or just accessed from the external hard drive, as needed. As for programs, most of those will need to be reinstalled from either disk or the Internet, as copying them breaks their software keys, etc. Note that this entire process will take hours, perhaps days, to complete. StuRat (talk) 00:50, 2 September 2013 (UTC)

StuRat beat me to it! ;) Basically external HDDs are a very useful thing to have when doing something like this (assuming, of course, you mean software); I purchased a 1TB USB hard drive for about CAD$70 a couple years ago. They can probably be found for cheaper now. --.Yellow1996.^(ЬMИED¡) 01:34, 2 September 2013 (UTC)

For uploading videos to Facebook or YouTube: .wmv or .mpg (MPEG)?

Which of the 2 video formats shoud I use to have a better video, or visual, quality after I upload a video to Facebook or YouTube? I know that WMV is for computer use and internet streaming and .mpg is for video CDs among a few other things, but they both can be uploaded to and played on the Internet. Willminator (talk) 20:12, 1 September 2013 (UTC)

Generally WMV will give you better quality for the same file size. Which combination of size and quality you get in each case depends on exact settings though. If you already have the video in one of those formats (or any other that YouTube accepts) and it isn't prohibitively large, then upload what you have. You will never gain quality by changing the format. KarlLohmann (talk) 21:28, 1 September 2013 (UTC)

I have a software called Format Factory that converts one format to another format. I put some videos from my camcorder to my computer, editted them in Windows Movie Maker, and then published to my computer, which was automatically published as .wmv. On Format Factory I converted the .wmv file to an mpg file, so I got 2 copies of my Windows Movie. The .mpg movie copy turned out to be smaller in size than the .wmv movie for some reason (Why?). So, I'm trying to decide which of the 2 movies to upload on the Internet for better quality. Willminator (talk) 02:12, 2 September 2013 (UTC)

In this case, the .wmv is likely to be better. Converting to .mpg cannot exract more quality than was present in the original .wmv. Consider the analogy of copying out a handwritten work. If the original is in poor enough handwriting to be near-illegible, then getting someone to copy it out in neater handwriting is only going to be good as far as the copier can read the original. If the original should read "orange", but looks like "orovje", then all you end up with is "orovje" in very neat handwiting. MChesterMC (talk) 09:30, 2 September 2013 (UTC)

I'd personally suggest, if available, the H.264 format. Containers like .avi, .m4v, and .mp4 are all able to use H.264, and it's the format that YouTube itself processes to. Many editing and post-processing applications will allow you to render and export in H.264 especially optimised for YouTube, including iMovie and Premier Pro. If not H.264, I'd suggest another MPEG format (H.264 is part of MPEG's work) over WMV, as it's industry standard and it's what WMV is based upon. WMV is non-standardised, so can cause transcoding errors and lossy playback if not processed correctly.  drewmunn  talk  21:36, 1 September 2013 (UTC)

...But be prepared to wait a long time in the uploading process! (Unless YouTube's uploading service has drastically changed over the past couple years); I used to be a heavy user years back, and one time I waited 40+ minutes for a thirty second AVI file to upload! Though, of course, if high-quality video is a must, then there's really no other way than to wait. --.Yellow1996.^(ЬMИED¡) 01:37, 2 September 2013 (UTC)

.avi isn't the best container out there, I prefer .m4v and .mov by far. With a H.264 .mov, it'll upload in 1080p (or higher, in the old days, when I did upload a 2K once) and process it in not much slower than real-time. The actual upload process will differ depending on your personal upload connection, but as AVI stores each frame with so much data, it takes a long time for the upload to complete. I personally never use AVI any more; if I want to store as much as possible per frame, I'll use DPX, but for final exports, .mov is wonderful, and .m4v is still easily usable.  drewmunn  talk  10:34, 2 September 2013 (UTC)

Yeah I like .MOVs as well. That's actually what I ended up converting those AVIs to in order to get better upload time (though the quality was degraded, it wasn't unacceptable.) I personally use the wonderful Total Video Converter aww no article?! ;) (not free!) to do all my converting over the last few years, and I love it; though the media player that's bundled with it isn't very good. --.Yellow1996.^(ЬMИED¡) 16:09, 2 September 2013 (UTC)

I've got Adobe Media Encoder (through my work; I wouldn't pay that much just for a hobby!), but before that I could never find a good encoder. It's a shame I didn't know about Total then…  drewmunn  talk  16:19, 2 September 2013 (UTC)

Yes it's quite nice (except the media player, as I mentioned above...) and offers pretty much every possibility in terms of converting that you could want; and as an added bonus it does a very good job of it! ;) --.Yellow1996.^(ЬMИED¡) 16:38, 2 September 2013 (UTC)

So I just uploaded both videos to Facebook. I noticed that the video screen of the .wmv video is larger than the video screen of the .mpg video. It's not like that in my computer where the screens are of the same size. Why? Is it Facebook automatically trying to improve the video quality by making the .mpg video smaller? Willminator (talk) 19:23, 2 September 2013 (UTC)

Pretty much. Your WMV is higher quality, and therefore can be displayed larger than your MPEG, which is of lower quality. Your computer's media player is displaying them at the same size by default - if you put them side by side then you'd probably notice that the WMV looks better (I know Windows Media Player does this.) Showing it smaller is displaying it at it's intended resolution; if you made it bigger it would probably be all pixelated/have noticeable quality degredation... --.Yellow1996.^(ЬMИED¡) 01:01, 3 September 2013 (UTC)

But I bet it's possible one could still tell the difference in quality between the 2 in terms of crispiness and brightness despite the wmv being displayed larger than the mpeg, right? Willminator (talk) 12:39, 3 September 2013 (UTC)

More than likely. Especially if this is a real-life video; not something like a cartoon. --.Yellow1996.^(ЬMИED¡) 16:01, 3 September 2013 (UTC)