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September 29

clip pages from a PDF

Is there a free or low-cost program (for Windows) to copy a page or range of pages from a PDF to another (PDF) file? Bubba73 ^{You talkin' to me?} 00:27, 29 September 2011 (UTC)

If you're not afraid of the command prompt, you can do this with pdftk. An example from the web site:

pdftk A=one.pdf B=two.pdf cat A1-7 B1-5 A8 output combined.pdf

copies pages 1–7 of one.pdf, pages 1–5 of two.pdf, and page 8 of one.pdf, in that order, to combined.pdf. There are GUI frontends for pdftk as well. -- BenRG (talk) 01:53, 29 September 2011 (UTC)

This will probably be used a limited number of times, so command line is probably OK. Thanks. Bubba73 ^{You talkin' to me?} 02:04, 29 September 2011 (UTC)

If the command prompt gets you down, google "pdftk GUI" and you'll find graphical versions of the same program. --Mr.98 (talk) 11:28, 29 September 2011 (UTC)

Another good tool is PDFfill Tools.You can use it to split, reorder, merge, etc PDF documents. - Akamad (talk) 02:12, 29 September 2011 (UTC)

Thank you, PFDFill Tools works very nicely.

Resolved

Bubba73 ^{You talkin' to me?} 15:36, 29 September 2011 (UTC)

.com domain names of countries

Hi, I m wondering if any country can demand to appropriate a .com name with its name ? For my case, tunisie.com where owned by the Tunsian government and used for ben Ali propaganda [1]. But after the Tunsian Revolution, I don't know why, the domain became free and a French company has reserved the domain [2] and created a tourist website (www.tunisie.com). Can the Tunisian government take back the domain name ? How ? --Helmoony (talk) 02:40, 29 September 2011 (UTC)

Unlikely. This is discussed at Trademark#Domain names, Uniform Domain-Name Dispute-Resolution Policy, Cybersquatting and Anticybersquatting Consumer Protection Act. The legal issues (not policy issues) in France like those involved in AFNIC cases are also relevant since a dispute could be brought under French law if the company currently in control of the domain name is French and the registrar Gandi is also French [3], and we don't really cover that part. Generally, there is some protection for trademarks & service marks and in some places for personal names but no protection for geographical indicators/identifiers. It seems there have been proposal to extend protection to geographical indicators/identifiers but they've been rejected [4] [5]. This seems to be affirmed by recent cases e.g. [6]. From [7] it seems there have been some successful cases with geographical identifiers/indicators but only when trademarks were also involved.

The onlymost likely chance of success I can imagine is if there was something dodgy involving the French company gaining the domain name. For example, if it was transferred by rogue Tunisian government agents to the French company (probably for a payment/bribe) then the Tunisian government may be able to argue the original transfer was illegal and should be reversed but I don't really know how likely that is to succeed. If it was simply a case of the domain name expiring because the government didn't renew it then the only option is likely to be for a negotiated transfer which will depend entirely on the current owner of the domain name.

Edit: Thinking further perhaps I was too quick to dismiss one possible avenue. Since the French do tend to care about geographical identifiers/indicators, it's possible a dispute in a French court will succeed. I can't find much info in English on French law surrounding domain names, in particular whether there's any protection of all geographical identifiers/indicators (as opposed to those like Champagne, Wiener etc that may be specifically protected).I found [8] which suggests there is some protection although it's a bit unclear whether it applies to country names from the summary there and it seems to largely concern .fr domain names. And it's a new law as a result of the old law being overturned in court so hasn't been tested yet. I haven't yet found any recent info on how disputes like those involving .com domain names have been handled in French courts. Note that since the owner appear to be running a legitimate related business from the domain name, this will make a case more difficult.

Nil Einne (talk) 03:51, 29 September 2011 (UTC)

P.S. I just remembered [9] (admitedly old now) and while looking in to that I also found [10] which reaffirms what I was saying about the unlikelyhood of success for anything other then the possibility under French law or if there was a dodgy transfer.

Nil Einne (talk) 05:13, 29 September 2011 (UTC)

Thank you a lot. I m gonna make what is necessary to persuade Tunisian authorities to try something legal in France. Thank you a lot for the references. --Helmoony (talk) 22:07, 29 September 2011 (UTC)

Iteration over an infinite grid

I have a problem where I need to find a configuration of points on a grid. Instead of trying them manually, I'm trying to test cases with Python until I find a working one. Say I have 4 points. I can't simply nest for-loops, because there is an infinite number of lattice points that the 4th point could go on, and I would never change the other 3 points. How could I properly iterate through these cases? I thought of restricting it to a grid, and if no match is found, increasing the grid by one in each dimension, but that would cause a lot of redundancy, because there are many cases in an n x n grid that would fit in an n-1 x n-1 grid. It'd be possible to exclude those cases, but it'd be great if there were a more elegant solution. Does anyone know of a good method? KyuubiSeal (talk) 04:59, 29 September 2011 (UTC) for j=1 to i;

Make the limit of each iteration be the current setting of the previous iteration variable:

for i=1 to n;for j=1 to i; for k=1 to j; for l=1 to k do test (i,j,k,l)

or whatever you language syntax is. n can be infinity if it does not matter if you never terminate. Graeme Bartlett (talk) 09:40, 29 September 2011 (UTC)

That assumes the problem is symmetric in i,j,k,l. You will never test (1,1,1,2), for example, but you don't need to if testing (2,1,1,1) gives you the same answer. For a non-symmetric problem, iterate across points with a constant sum s=i+j+k+l:

for s=0 to n; for i=0 to s;for j=0 to s-i; for k=0 to s-i-j do test (i,j,k,s-i-j-k). Gandalf61 (talk) 10:17, 29 September 2011 (UTC)

That's really concise. :D Also, it'd work well with recursion, so I don't need to have 8 nested for-loops (2 for each axis). Thanks! KyuubiSeal (talk) 12:47, 29 September 2011 (UTC)

Can you tell us something about the points and the test performed ? If you know the distance of the points from one another, for example, then a different method might be more efficient. And can the test only be performed with all 4 points, or is there a subtest that could be used to establish that 3 of the points are correct, before adding the 4th ? If so, we could greatly improve the efficiency again. StuRat (talk) 17:04, 29 September 2011 (UTC)

It's one of the "place n dots to get a rows of b" problems. KyuubiSeal (talk) 17:26, 30 September 2011 (UTC)

are computer font formats vectors?

Do opentype and other formats use vectorized system?Exx8 (talk) —Preceding undated comment added 15:07, 29 September 2011 (UTC).

Yes. Anything based on TrueType is going to be vector based (aka scalable). -- kainaw™ 15:28, 29 September 2011 (UTC)

A great majority of TrueType fonts are spline (vector) only, but the TTF and OpenType formats accommodate sbit data, which means multiple scalable data bitmaps can be embedded into the TrueType file, and it's possible to have a TTF that has only bitmap data. This is especially useful for small-size screen fonts where the hand-wrought work of a human designer gives a better result than would the rasterised output generated by evaluating only a spline representation. Being TrueType even bitmap support is rather complicated - bitmap data itself is stored in bdat (or something else with MS stuff), and there's a bunch of other sections in the TTF file format to define mapping etc. of sbit data. This discussion suggests that enabling ClearType (which is the default, I think, for most recent Windows systems with suitable displays) disabled effective rendering of bitmaps embedded in TTFs. I can't find a useful .ttf file dissector, and my cursory attempt to write one myself using FreeType2 foundered on the relevant section of the tutorial not being written yet. If I figure it out tomorrow I'll post something here. It'd be interesting to run it on a recent Windows install and see what fonts, if any, retain sbit data. In particular, is Terminal still bundled with Vista/7 and if so is it still one of the old bitmap-only font formats that shipped with Win98 or is it an sbit TTF. (I don't have windows to hand to look right now). -- 2.122.75.122 (talk) 23:56, 29 September 2011 (UTC) (Finlay McWalter, still logged out)

Photo sharing website

I'm looking for a website or service to help me with the following situation: I went on holiday with a group of friends, and we each took a bunch of photographs. I'd like to have everyone share their photos with everyone else, but privately (ie I wouldn't like them to be uploaded to e.g. Facebook). MobileMe used to have a service whereby someone could create a photo album, protected by a password, which anyone who knew the password could access (to see the photos, or download them in one go as a ZIP file) and upload to. Unfortunately, MobileMe is no longer open to new registrations. Do you know of any alternatives? I'm fairly computer literate, but my friends are... less so..., so simplicity would be a plus! :)

Thanks a lot in advance! — QuantumEleven 15:53, 29 September 2011 (UTC)

I think Flickr should meet your requirements. Any/all pictures uploaded can be marked a private, but available to friends and/or family. You can also create a group which would require a moderator's approval to join. This might be problematic if any of your group already use Flickr, however. --LarryMac | Talk 20:10, 29 September 2011 (UTC)

Dynamic online polling system?

My research institute has a student-run seminar series and we want other students to be able to put forward a) topics b) questions to be answered by people presenting the topics and c) votes for topics. Does anyone know of an online polling system that would let us query students in that way? --129.215.47.59 (talk) 16:04, 29 September 2011 (UTC)

September 30

How do I edit a template?

I tired to edit the template on mass murderers [11], following an RFC [12]. It ruined the Kip Kinkel article. What am I doing wrong? Noloop (talk) 02:26, 30 September 2011 (UTC)

If you ask this question on Wikipedia:Help desk you may get a better response; that's the place for asking questions about how to edit Wikipedia. --Colapeninsula (talk) 10:21, 30 September 2011 (UTC)

You messed up the }} for the end of the #if. Graeme Bartlett (talk) 12:14, 30 September 2011 (UTC)

multiple user e-mail account

Hello. I need to find a web-based e-mail service that allows multiple people on different computers to access a single account. My personal account is on gmail, but its terms of use say that multiple users accessing from different locations is not allowed. What I need is an account that allows four or five people in widely diverse locations to send and receive at the same address. Any recommendations? Thank you. — Michael J 12:54, 30 September 2011 (UTC)

Isn't delegation the answer? You set up the account you want to use - then delegate it to the four or five people? --Cameron Scott (talk) 13:51, 30 September 2011 (UTC)

That works only if everyone who needs to access the account uses gmail for their own account, which is not the case. It doesn't have to be gmail; we just need to have an e-mail address that a small group of people can access, not just an individual. No one of us will have priority over the others. — Michael J 07:06, 1 October 2011 (UTC)

I'm not sure how you'd do that - it's a receipt for disaster anyway for various legal reasons. --Cameron Scott (talk) 10:30, 1 October 2011 (UTC)

OK, thank you. I guess if it can't be done, it can't be done. (But Mr. Scott, I don't quite follow why you believe it would be dangerous.) — Michael J 17:19, 1 October 2011 (UTC)

Wall St. Tickers

Have any of the computers which control the displays of the ticker symbols and numbers at the big exchanges like the NYSE or the NASDAQ, the displays that the significant traders pay attention to and make decisions off of, ever been hacked or displayed wrong numbers at any time? 20.137.18.50 (talk) 14:45, 30 September 2011 (UTC)

Traders do not care what the stock-price says on any ticker. Traders pay attention to bids and call from other registered brokers. The ticker is sort of a time-averaged history or weighted moving average of recent executions weighted by volume. At any given instant, any trader may bid or offer at any price they like. Whether they make a sale at that price depends only on two factors: whether another broker has made a corresponding bid or offer at that price, and the precedence rules that the stock exchange sets for bid/offer exchange.

A more realistic question is: "has any broker ever executed a trade that they wished they had not, due to computer error (including unauthorized access)?" The answer is, "probably every five minutes." Nimur (talk) 17:56, 30 September 2011 (UTC)

Relatedly, wasn't there a case about a year ago (maybe less) of a reasonably large stock market dip being caused (or alleged to be caused) by a computer error? --Mr.98 (talk) 18:00, 30 September 2011 (UTC)

There was something early this year with the London Stock Exchange when they migrated to Linux [13] [14] [15] [16]. I don't know how big of an issue it was, though — frankie (talk) 18:23, 30 September 2011 (UTC)

Flash crash is probably what you are thinking of. Dragons flight (talk) 18:27, 30 September 2011 (UTC)

Yes, that must be it. I didn't know it had been given a rhyming name already. :-) --Mr.98 (talk) 14:31, 1 October 2011 (UTC)

Privacy and Encryption

Being a bit more than paranoid about privacy (in the context of digital security), I find myself annoyed when I have to send some private data over the internet. Let's say I have to send a couple of pictures or some excel sheet with personal financial data to a friend. I can attach them to an email or (if the file is rather large like 1GB) use a service like yousendit. What irks me is that anyone and everyone that info is going to pass through electronically, will keep a copy of the data. And it will lurk around and it will stay there for years...perhaps forever. Google will archive it and someone can see it twenty years later (rather easily I think). To turn the data into meaningless stream of bits, encryption is the obvious answer. Unfortunately the people I am communicating with are not too computer savvy (and not nearly as paranoid about security as I am) so I can't trust them to implement a protocol properly. My question is, is there some sort of a software which can just encrypt any kind of data with something strong like AES-256 but make the output file into an executable (recipients are using windows) so that the decryption algorithm is included with the file. The recipient just downloads the file (a single executable), double-clicks it, types in the key, and voila the pictures are dumped in the folder. I know about winrar but it doesn't really give you a choice of algorithms/strengths to use. In fact I don't even know what algorithm it uses (does anyone know) but it definitely does have the advantage of splitting up the file into smaller chunks. It is also proprietary and just like how the experts have drilled into my head, I try very hard to stay from these proprietary black boxes (no real cryptographer believes in security by obscurity). Its probably super weak and for all I know (remember I am paranoid) there's probably a back-door built into it leaking info to winrar and/or the NSA. I would prefer something small, simple, possibly free and open source. Seems like something like this should already be out there and I will trust open source a bit more (thinking more people would have looked at it so its much harder to build a trap in it). Seems like something easy too. Just something a notch below from writing my own software. I would write my own software but lack the computer science knowledge and the expertise in cryptography to write a safe secure efficient implementation. Something which gives you a choice of algorithms and key strength would be absolutely ideal. Thanks you.128.138.138.122 (talk) 22:02, 30 September 2011 (UTC)

This is not as simple as you want for your non-computer-geek friends, but I would educate them about TrueCrypt and use that. Or WinRAR, where this page says it uses AES encryption with a 128-bit key. Comet Tuttle (talk) 22:25, 30 September 2011 (UTC)

7zip supports AES-256. I don't know about self-extracting exes but it's very easy to install the program in a few seconds, open the encrypted file, enter password, and extract. TrueCrypt is more advanced and designed for strong encryption. It creates virtual encrypted drives with a lot of options for cryptographic algorithms. Both programs are free and open source. AvrillirvA (talk) 22:31, 30 September 2011 (UTC)

If the recipient doesn't use 7-Zip or WinRAR but does use WinZip, you can send an AES-encrypted ZIP. You need to be careful here because there's an older, insecure ZIP encryption standard (not AES-based) that some open-source tools will use if you request "encryption", without so much as a warning. I think that 7-Zip does support AES in ZIP.

(ZIP AES is not proprietary; it's publicly documented as part of the official ZIP standard. RAR's AES implementation is also "documented" in the official UnRAR source code, and I think people have analyzed it. It's fine, as far as I know, though there were weaknesses in earlier versions of the RAR format.) -- BenRG (talk) 00:01, 1 October 2011 (UTC)

Microsoft provide encryption within their applications (including Excel), and this might be sufficient for your purposes, though it is not as secure as some of the above suggestions. I use Word's and Excel's encryption for sending confidential documents, but I haven't fully tested whether Word encrypts embedded images. In all cases, you will need to send the password by a secure method independent of the internet. If you are looking twenty years ahead, then I suggest some form of lengthy "one-time pad" encryption (e.g. your favourite novel with an added lengthy randomiser) because future computer power for cracking existing encryption is unknown. On the subject of paranoia, does anyone know which of the commercially available encryption software packages contains a "back door"? Dbfirs 09:28, 1 October 2011 (UTC)

One-time pads are virtually useless. The hard part of encryption is key management, i.e., making sure the key is available to the good guys when needed, but never available to the bad guys. A one-time pad has to be machine-readable and has to be stored in a location that's inaccessible to the bad guys, and if you can do that then you might as well store the document itself in the same place, unencrypted. A novel can't function as a one-time pad because it isn't random. One-time pads have to consist entirely of independent random bits.

I don't know if Microsoft Office's encryption is any good. It wasn't in the old days (nor was ZIP's), but times have changed.

Your question about back doors is too broad to be answered. There are a lot of snake-oil products out there designed by well-meaning but incompetent people. These products don't have deliberate back doors but might as well because they're very insecure. Excluding those products, I think that most cryptographic software can be trusted. It's much harder than you might think to design a back door into a cryptosystem without people catching on. -- BenRG (talk) 02:52, 2 October 2011 (UTC)

I mentioned one-time pads because they are uncrackable, but I agree that their usefulness is limited, and that a novel is not ideal as a substitute for a one-time pad, though with appropriate randomisation it can be almost impossible to crack without inside knowledge. The problem with current encryption methods is that they assume limited computing power. This might change unexpectedly in 20 years.

By "back door", I was thinking of something like the old Novell network software in which a carefully timed sequence of key presses during boot-up gave admin access without logon, or the "spare password" built into some software for maintenance purposes. Rumours that the NSA have a back door to Microsoft encryption are probably false since their powerful computers can probably crack the encryption (64-bit?formerly 40-bit) in a reasonable very short time. From Office 2007 onwards, Microsoft claim to uses 128 bit AES encryption, and this should be reasonably secure with a decent password. Dbfirs 12:32, 2 October 2011 (UTC)

What of _NSAKEY?Smallman12q (talk) 14:23, 3 October 2011 (UTC)

I had thought encryption would be part of the Office Open XML standard but it seems it's not, it's a Microsoft addition [17]. Either way of course, Microsoft's implementation is closed sourced and proprietary. Microsoft does say they use AES although you can change encryption method [18]. Because of the commercial interest, flaws in Office encryption implementations are usually found if they exist but I believe for Office 2003 (when properly set up, not with the default settings) and the Office Open XML present in 2007 and 2010 encryption there is currently no known flaws [19] [20]. Nil Einne (talk) 05:54, 3 October 2011 (UTC)

Thanks for the interesting links. I've corrected my comments above based on your research. Dbfirs 07:17, 3 October 2011 (UTC)

You're probably looking for something like AxCrypt which creates a password protected executable.Smallman12q (talk) 14:23, 3 October 2011 (UTC)

October 1

Vulnerabilities in find and workarounds

I'm aware of the inherent vulnerability using find and -exec, as it's discussed ([21]) elsewhere. So for a workaround, a few questions. 1) Is there a convenient list of all bash tokens that could be used for escaping and exploits like this? In other words, can someone point me either to some regexes that sterilize things for the command line or at least the list so I can write them myself? and 2) Is there a simple way for me to call an abitrary command-line program without dealing with the shell. Like in perl for instance I seem to remember hearing that this was possible. Any other practical workarounds would be useful too. Shadowjams (talk) 00:32, 1 October 2011 (UTC)

At the shell prompt, (in bash), type man builtins to get a complete listing of all shell built-ins, special-characters, and commands.

The safest thing to do is to use file-permissions to deny a script from accessing, executing, editing, deleting, or copying files that it doesn't have permission for. Often, this means creating a separate user-account with the minimum permissions you need for the script; this allows Unix to sandbox the script-process for you (automatically eliminating an entire class of security-risks).

Perl can execute shell commands in several ways; the easiest is to use the ` character, documented here (as PERLOP `STRING`); or the similar system and exec commands. Perl isn't necessarily safer - if you don't know what the script is doing, translating it to another language sure doesn't help. Nimur (talk) 01:15, 1 October 2011 (UTC)

No, you shouldn't use backticks (`) for this because it invokes shell command parsing, which is precisely what the OP wants to avoid. You should use system with more than one argument.

I'm not sure I understand the question, though, because find -exec doesn't use shell parsing either. If you look at the linked page, the problems are (1) filenames that begin with - being interpreted as options, which has nothing to do with the shell, and (2) explicitly executing the shell with -exec sh -c "...". To avoid the first problem you have to read the documentation for the particular utility you're using, since the exact treatment of command-line arguments is program-specific. Many (not all) utilities accept -- as a signal that all later arguments are file names, not options. To avoid the second problem, just don't explicitly invoke the shell.

I would strongly suggest avoiding shell utilities in favor of a decent programming language with a large selection of library routines. Perl is okay, but ever since I learned Python I've stopped using Perl for this kind of thing. In Python you can get find-like functionality with os.walk:

      import os

      size = 0

      for dirpath, dirnames, filenames in os.walk('.'):
          for filename in filenames:
              if filename.endswith('.zip'):
                  size += os.stat(os.path.join(dirpath, filename)).st_size

      print(size)

This prints the total size in bytes of all files with names ending in .zip below the current directory. (Not that that's what you wanted to do, but I wanted a nontrivial example.) The point is that you can do a lot of things without invoking command-line utilities at all, and thus you avoid having to stringify the command arguments and parse the output, and all of the security risks and bugs associated with that process. -- BenRG (talk) 03:37, 1 October 2011 (UTC)

Both excellent answers, thank you. That covers pretty much all the issues I was wondering about. Shadowjams (talk) 03:53, 3 October 2011 (UTC)

Torrents - are these just pure leechers?

When you're seeding a torrent and you see peers downloading lots of data from you, but their completed percentage never rises above 0.0% - are these typically users who have modified their client (or are using a hacked client) to make it report incorrect stats to avoid having to upload anything? i.e. being pretty much a textbook leech (I'm using uTorrent, btw)? I've noticed a few of these on my torrents recently and have considered blocking those specific IPs. --Kurt Shaped Box (talk) 01:30, 1 October 2011 (UTC)

Not necessarily. At least some clients, as a bandwidth optimization, don't report the acquisition of a block to a peer that is known to already have that block. (See "HAVE suppression" in the spec here.) -- BenRG (talk) 03:40, 1 October 2011 (UTC)

You can modify how much you upload by right clicking the torrent and choosing how much you can upload, it's not a hack. Bluefist ^talk 17:10, 6 October 2011 (UTC)

Looking for spam

Hello. I'm doing an assignment for which I need a fairly large sample of junk email. Viagra ads, enlarge your manhood, Nigerian scam... everything is fine. Is there some service from which I could retrieve such sample? 88.112.55.242 (talk) 07:57, 1 October 2011 (UTC)

Simply register a domain name (and get your ISP to host it and forward any emails), sign up for some (free?) porn, join a warez forum, and express an interest in buying drugs over the internet. It won't be long before your mailbox will be flooded with more than enough spam to keep you busy for years. Responding to any of the spam will almost certainly increase the amount and variety of spam. In case it is not obvious, never actually give anyone information about your bank account and use a disposable email account for your research. Astronaut (talk) 09:36, 1 October 2011 (UTC)

There are dozens of spam collections on the internet for testing algorithms. [22], [23], [24], to give just a few examples. gnfnrf (talk) 14:28, 1 October 2011 (UTC)

Turning off Search Indexer

Microsoft's Search Indexer appears to be quite a resource hog on my Windows Vista laptop, and I almost never need to search for things - I'm quite organised and I have a good memory. I'm hoping I can free up some resources by stopping the indexer, without it breaking something else. Older versions of Windows had a way to turn off the Search Indexer, but I cannot find the control in Vista. So where has it been moved to?

Type services.msc into the start menu search box or command prompt, find the entry called "Windows Search" and double click it, set "Startup type" to disabled and click "stop". AvrillirvA (talk) 10:27, 1 October 2011 (UTC)

Learning PHP

After half a year of learning XHTML, CSS and JavaScript, it is time to pick up PHP. For files on localhost, can I use my own computer as a server? Do I need to install extra software, such as a PHP interpreter? — Preceding unsigned comment added by 59.189.219.114 (talk) 13:53, 1 October 2011 (UTC)

Yes, you'll need to install server software. When I did this (five years ago) I chose XAMPP, or in fact xampplite which is smaller. (It's Apache, really.) You can start the server, test some PHP locally, and stop the server when you're finished.  Card Zero  (talk) 14:15, 1 October 2011 (UTC)

Depending on what your operating system is, you'll need to install LAMP, WAMP, or XAMPP. Then, you start the webserver on your computer and access the PHP pages with a web browser connecting to localhost. -- kainaw™ 14:25, 1 October 2011 (UTC)

(edit conflict) There are lots of bundled packages of Apache, MySQL, and PHP. Depending on your OS, they are called WAMPs, LAMPs, or MAMPs. (Why we have three separate articles for what are essentially the same concepts, but on different OSes, I do not really know.) There are oodles to choose from. On my Mac I use XAMPP and have never had troubles with it. On my work PC I use EasyPHP and it works fine. --Mr.98 (talk) 14:27, 1 October 2011 (UTC)

making a film

So, I wanted to fit a bunch of pictures together to create a short film, like a slide show, but a bit quicker than I expect they could manage, and whilst experimenting with my video editor (avidemux), I found that I could open pictures in that and stitch them together into just such a film. However, if I try to add a picture that is not the only one in the folder, it adds the whole contents of that folder, but with all but the first in the wrong colours, all bright and jumbled up instead. if I move things in and out of the folder one by one, it can only find the last one, so no easy way around that. And now it turns out, if I save it and load it again, it all comes up in the wrong colours anyway, and with all coloured dots over the pictures as well. Meanwhile, even the right colour images are of a rather lower quality than they were originally.

So, firstly, is there any way I can stop it doing all of these, and actually put the film together like this? If not, is there anything else I can get that would do a better job?

148.197.81.179 (talk) 19:31, 1 October 2011 (UTC)

http://electron.mit.edu/~gsteele/ffmpeg/ ¦ Reisio (talk) 19:50, 1 October 2011 (UTC)

I'm afraid that just looks like a long string of random letters and words to me, I have no idea what I am supposed to do with this, or even if it is something that can do what I want or merely a description of a program that exists elsewhere. 148.197.81.179 (talk) 12:14, 2 October 2011 (UTC)

How to view .TIF (.tif) files?

I downloaded the 25,000*16,000 resolution wallpapers for the Rage video game. I'm wondering what software can open these pics? Does anyone know? 65.66.126.217 (talk) 21:03, 1 October 2011 (UTC)

Assuming Windows XP / Vista / 7, MS Paint should be able to open them and convent them to jpg or something else more suitable. AvrillirvA (talk) 21:02, 1 October 2011 (UTC)

Well, I'm on Vista and MS Paint wasn't able to open them. Paint displays the following.

"Paint cannot open this file. This is not a valid bitmap file, or its format is not currently supported." 65.66.126.217 (talk) 21:09, 1 October 2011 (UTC)

Hmm. Try IrfanView, it should be able to open almost any image format AvrillirvA (talk) 21:17, 1 October 2011 (UTC)

Hey thanks AvrillirvA, that's an impressive software. CHRISTIANgamer97 (talk) 04:03, 2 October 2011 (UTC)

Download the smaller versions if you want smaller ones. There's one that's 2560x1600 and it's probably still bigger than you'll need. ¦ Reisio (talk) 23:30, 1 October 2011 (UTC)

Backing up/cloning a failing hard drive

A computer that I have is complaining of "imminent hard drive failure." I take it to mean that the hard drive is failing the BIOS's health checks. You can still make it boot to Windows but some files may not be reliably readable.

How do you back up or clone a failing hard drive before it fails completely? --71.185.179.174 (talk) 23:24, 1 October 2011 (UTC)

I'd use SystemRescueCD and ddrescue, but only if you're having trouble copying personal data — the OS files aren't worth it. ¦ Reisio (talk) 23:35, 1 October 2011 (UTC)

October 2

Telnet port numbers

I'm pointing out here and now that this is a homework question. Don't you wish all homework questions were that blatant about it? The question asks if clients A and B initiate telnet connections to server S at about the same time, what source and destination port numbers would A, B, and S use. Wouldn't A & B both use port 23 since that's the default port for telnet? It then goes on to ask whether the ports would be the same or different based on whether the connections (A and B) were coming from the same or different hosts. Wouldn't it work in a similar fashion to HTTP and its use of port 80? I can't seem to find the text relating to this and don't recall reading it. Thanks for any assistance, Dismas|^(talk) 02:54, 2 October 2011 (UTC)

Hi Dismas. Clients A and B would send packets to port 23 on Server S. However, they would each send these packets from a different randomly-generated source port. You can see this if you open two command prompts by going to Start → Run... → cmd twice and typing telnet towel.blinkenlights.nl into one of the windows. In the other window, you type netstat -an and you'll see each TCP/IP connection to your computer. Look for the connection with the destination port like this: 94.142.241.111:23. That number is a socket — an IP address followed by a colon and the port number. But, in short, port numbers are pre-determined for the server (for the listening application). They are not pre-determined for the client application. As for the second question, they would also be different, even if they were coming from the same computer. Operating systems determine the return path by using different port numbers. One telnet session may have the return address of 192.168.1.100:5000 and another 192.168.1.100:5001. If the telnet server sends a packet to 192.168.1.100:5000, your computer will know that the packet is destined for the first telnet session.—Best Dog Ever (talk) 04:59, 2 October 2011 (UTC)

For more about the client port selection, see Ephemeral port. Unilynx (talk) 13:39, 2 October 2011 (UTC)

Thanks to you both! A much better explanation than what my teacher normally gives me! Dismas|^(talk) 02:55, 3 October 2011 (UTC)

What may be missing from a complete picture is that while the server is listen()ing on port 23, as soon as it accept()s the connection, a new ephemeral port is created to handle that particular TCP connection. So while connections are initiated at port 23, none of them occupies it permanently. --Stephan Schulz (talk) 20:15, 3 October 2011 (UTC)

What? The connection is permanently identified by the (sourceaddr,sourceport,destaddr,destport) tuple. One of those numbers is 23. Run netstat if you don't believe me. 67.162.90.113 (talk) 23:29, 3 October 2011 (UTC)

I always assumed that the new socket returned by accept() also implied a new port. Seems that I was wrong. Thanks for enlightening me. BTW, I ran netstat on an ssh connection, given that the number of open telnet ports is really quite limited nowadays ;-) --Stephan Schulz (talk) 13:26, 4 October 2011 (UTC)

YPbPr Problem

Hello all.

I've got a slight problem related to my old TV. See, for a few years now, I've been playing my Xbox on this fairly old TV, on standard resolution. As the TV's about 3 years old, I'd assumed it couldn't display HD. But this morning, I noticed a little sticker on the front that says 'HD Ready'. Now the problem is, I've got an Xbox HD cable, which I worked out is a YPbPr cable. The table on HD Ready says that if the TV says it is HD Ready, it must be able to accept YPbPr input, and indeed, when I cycle through the channels, there is one labelled 'YPbPr'. The problem is, I can't see where I should plug my YpbPr cables in. Here's a picture of the back: http://www.flickr.com/photos/68190540@N04/6203422208/lightbox/ (Apologies for the terrible quality). But basically, there's an input marked DVI (I understand that is an HD computer cable), One marked D-SUB, one called PC Audio, A yellow (I think S-Video?) and two sound input, and A scart input. There's no YPbPr input that I can see. Do I need to buy a signal transformer of some sort? Thanks. 92.7.30.242 (talk) 10:56, 2 October 2011 (UTC)

Also, here's the product details: http://www.ciao.co.uk/Swisstec_J19_1__6615521 . Any help is appreciated! 92.7.30.242 (talk) 10:58, 2 October 2011 (UTC)

Are you sure the cable is YPbPr? The colour of the three plugs should be a guide so if you have red, white and yellow that is just sound + composite analogue video. Do the TV's menus or the user manual give you any information about switching one of the labelled inputs to YPbPr? Sometimes, the SCART connector can be set to receive composite or some kind of component video (though perhaps not YPbPr). It also depends on which type of Xbox you have: this one: Xbox, or this one: Xbox 360 as to what output it is capable of producing. Astronaut (talk) 16:05, 2 October 2011 (UTC)

It seems that your TV doesn't actually have a YPbPr input. I've helped someone set up an XBox before. I think it has an HDMI output that carries digital video & audio to a TV that has an HDMI input. In your case, you have only a DVI input but no HDMI. Maybe you can look into getting a HDMI-to-DVI adapter. The audio may not work, as DVI is video-only, at least the older implementations are. If the audio doesn't work, you can use analog or optical audio, but there's some complication. Once you plug in an HDMI cable, you cannot plug in the original analog A/V connector. There are slim audio adapters that can plug into the analog A/V output connector even with an HDMI cable plugged in. People have invented hacks to work around the plug interference problem without an adapter, but that involves removing the plastic housing of the standard A/V cable. See [25]. If this seems a bit complicated, I'll admit it is, but I don't have another suggestion. Good luck. --72.94.148.76 (talk) 16:19, 2 October 2011 (UTC)

Some TVs have YPbPr via the scart. I would check your manual to see if there is any mention of it. BTW, does your TV say HD ready or does it have the HD ready logo in the above article? If it's the former, this may not mean the same thing as implied by the logo. Nil Einne (talk) 16:40, 2 October 2011 (UTC)

On closer inspection, although on flicking through the channels it just says 'YPbPr', when you look in the menu, it says 'D-Sub (YPbPr)'. So i guess I'm going to have to get one of these : http://forums.bit-tech.net/showthread.php?t=154360 . Incidentally, it's a 360, and definitely YPbPr cables; they're red, green, and blue. 92.7.30.242 (talk) 17:39, 2 October 2011 (UTC)

I once owned a television in which the component inputs were striped downward across the same plugs as the composite inputs (which ran across). Looking at your photos, though, this doesn't seem to be the case. And as an aside (mainly to other answerers, not the OP), early XBox 360s did not have HDMI, it was added with the Zephyr series motherboards. See Xbox 360 hardware for details. gnfnrf (talk) 04:07, 3 October 2011 (UTC)

Right, the cables have arrived, I have hooked it all up, and my Xbox is now displaying in glorious HD! Thank you everyone who answered this question, I know that having to do tech support must be pretty annoying. Could someone please mark this as resolved? 92.7.31.251 (talk) 18:51, 4 October 2011 (UTC)

October 3

How do I make Windows MediaPlayer12 the default player again

Resolved

How do I reclaim all the file types, that MSMediaPlayer can handle, to play in MediaPlayer as default again?
(I use Windows Media Player 12 under Windows7Home).
--89.9.63.203 (talk) 06:05, 3 October 2011 (UTC)

Start -> Control Panel -> Programs / Default Programs -> Set your default programs -> Windows Media Player -> Set this program as default AvrillirvA (talk) 21:50, 3 October 2011 (UTC)

Perfect! Thank you! :-)
-- (OP) 46.212.181.97 (talk) 13:43, 4 October 2011 (UTC)

How to link two combo boxes (access 2007)?

I have a table with some fields and one of them is a combo box. I have created a form for this .

I add another field with combo box. How can i make , that when i select a combo box (example state) the other

combo only lets me choose cities from that state ?-- first question

Related to the first --- I also did some testing , like creating 2 tables (one state the other city) , and i have linked them with ID - state ID (one to many).

In the state table , it shows me with a plus + , the cities that i want. But i want to see them in a form , wich is not related to the two tables.

So i use combo box form control in the form , to select the field for state , and another combo for the city. I see the states with the first

combo box , but when i choose the other (city combo) it shows me all cities...... PLEASE HELP...

Thank u in advance .79.106.5.224 (talk) 06:57, 3 October 2011 (UTC)

Here's a way to do it with only one extra table:

1. Create a table called tblCities with text fields name and state (and add a primary key column if you want one). Populate it with some data (e.g. San Francisco/CA, Boston/MA, whatever).

2. In your form, create your two combo boxes. I will refer to them a cboState and cboCity. For cboState, set its Rowsource to SELECT tblCities.state FROM tblCities GROUP BY tblCities.state ORDER BY tblCities.state;. This will make it list all of the states in alphabetical order, but only list one of each state.

3. For cboCity, set the Rowsource to SELECT tblCities.name FROM tblCities WHERE ((tblCities.state)=[cboState]) ORDER BY tblCities.name;. This just means, select all the names (in alphabetical order) from the cities table where the state value is the same as whatever is selected in cboState.

4. Now, one last thing. By default cboCity will not update when you change the state. So we have to tell it to do this manually. Click on cboState, go into the Properties window, and then click on Events, then click in the space for on change and click the button with the three dots that appears, then choose "code builder." This will open the VBA editor.

4. Your screen should have your cursor just after a place that says Private Sub cboState_Change(). Add the following one line of code below this line: cboCity.Requery. Then save and close the VBA editor. This just means, every time cboState is changed, it should cause cboCity to refresh its options.

Let me know if that works for you. Now if you wanted to link back to the cities table for your data, it is slightly more tricky — you need to add a primary key field to that table, and have that primary key be linked to the cboCity combo box (you don't need to link the state combo box to anything because it is implied by whatever city it is, in this scheme). If you need the above modified for that purpose, just let me know. --Mr.98 (talk) 12:59, 3 October 2011 (UTC)

In-browser PDF display

A lot of my workflow relies on various PHP/Javascript programs I have made that display alongside PDFs in a browser window. I had made these programs to be compatible with Adobe Reader.

I run a Mac with OS X 10.6.8, using Safari 5.1 as my primary browser.

So I was somewhat surprised recently when Safari stopped using Adobe's plugin to display PDFs. At first I thought I had done something wrong, but now I see that this is a major compatibility problem with Adobe Reader and Safari 5.1.

Instead of opening a PDF in the Adobe plugin, it now sometimes displays a PDF with a minimal of editing features (it doesn't even display page numbers, which I need for my work), and the default Safari PDF reader does not recognize any hashtags like #page=, which used to make the Adobe Reader PDFs jump to whatever page I told it to.

So I'm looking for a PDF reader that can do four things, in descending importance:

1. Display in browser in OS X 10.6, either in Safari 5.1, or Firefox, or Chrome.

2. When viewing the PDF, it needs to have some easy, straightforward sort of way to see the page numbers, adjust the zoom, things like that. Adobe Reader's default tool bar at the top worked fine for this.

3. Ideally, extra bonus, it would be great if there was some way to programmatically (e.g. with a hashtag or Javascript) be able to tell the reader to jump to a given page (e.g. #page=5). I don't care how it does this — I'm happy to make small adjustments in my code to whatever the method is — but it needs some way of doing this. (This is because I deal with big databases that are indexed to various pages within these giant PDFs, and I need to be able to quickly see page 135 or whatever without too much hassle or tabbing back and forth.)

4. Can handle very large PDFs relatively fast — most of the PDFs I am using are between 20 and 150 MB in size, and some PDF readers (like the Preview application for the Mac) take forever to try and cache all thumbnails or other things, and are thus super slow. (The PDFs are composed of lots of grayscale photographs, primarily.)

Any suggestions? --Mr.98 (talk) 12:14, 3 October 2011 (UTC)

You could load it via swishpaper or flashpaper, of course then you're relying on Adobe Flash. The only fullproof thing I can think of is fully converting away from any binary format, to ordinary HTML. I feel your pain, man. ¦ Reisio (talk) 18:12, 3 October 2011 (UTC)

HTML would really not work. I don't mind relying on Adobe if it works, but I don't think SwishPaper or FlashPaper are fast enough to serve as an on-the-fly PDF reader, are they? --Mr.98 (talk) 20:01, 3 October 2011 (UTC)

You might want to take a look at pdf.js. It's very primitive in a lot of ways, but (a) it does do the page-number-as-anchor thing that you want, and (b) being written in JavaScript, you don't have to muck around with browser plug-ins. The demo seems to be very slow, but it's under active development (the main repo seems to be getting commits every day, even on weekends). Paul (Stansifer) 19:29, 3 October 2011 (UTC)

That's an interesting idea. I'm a little skeptical it will be able to handle my files without blowing up my browser, but it might be worth a shot... --Mr.98 (talk) 21:48, 3 October 2011 (UTC)

Although the default Chrome PDF reader does recognize #page tags, it inexplicably doesn't show page numbers. I swear I read somewhere that it was based on FoxIt, the only Windows PDF reader that doesn't suck monkey nuts, but unfortunately the full version of FoxIt doesn't seem to be available for the Mac OS. Have you tried skim? Maybe worth a go. Other than that.. why not downgrade? It's not like every new revision of the Mac OS gets worse as in Windows, but there have been inadvisable upgrades before (7.6 to 8.0, for example). Nevard (talk) 23:45, 4 October 2011 (UTC)

Odd Problem with Cell in Excel 2007

I copypasted the contents of a comment in the margin of an .rtf file from Word 2007 directly into a cell in Excel 2007. Now I want to remove the comment, as it has since become irrelevant. However, I can't. I can't even select the cell anymore. Is there anything I should do here? KägeTorä - (影虎) (TALK) 14:10, 3 October 2011 (UTC)

Have you tried deleting the entire row or entire column in which the cell lies? One thing I have learned to do in Excel is that when pasting and weird stuff happens, I first "Undo" ... then I select the destination cell, click up in the text area as though I wanted to type something into the cell, and then choose Paste. This tends to paste just text and does not attempt to paste text formatting. Comet Tuttle (talk) 16:06, 3 October 2011 (UTC)

I have tried to delete the row, but it won't let me. Clicking on the row, just highlights the first cell, unlike normally were it highlights the entire line. KägeTorä - (影虎) (TALK) 17:16, 3 October 2011 (UTC)

1: Try Shift+Space to select the entire row. 2: If you can't select the cell, maybe the protection settings got turned on? --Bavi H (talk) 23:58, 3 October 2011 (UTC)

You could also try including the rows above and below in your selection to be deleted (having copied necessary data elsewhere first of course). Dbfirs 08:49, 4 October 2011 (UTC)

I can't select the cell, or delete the row/coloumn (it just deletes the first cell in each row/column). I suspect this may be due to some pre-formatting that my agent has done. But they can't get rid of the comment, and nor can I. KägeTorä - (影虎) (TALK) 11:51, 4 October 2011 (UTC)

As a last resort, if this is is possible for your sheet, you could try exporting to CSV (comma separated variables) which you could edit in a text editor (such as notepad) if necessary, then re-import to a new sheet. Dbfirs 15:51, 4 October 2011 (UTC)

RSS for Reference desk?

How can I subscribe to Wikipedia:Reference_desk questions? I love to read it.

Yes, I can add this it to my watchlist, but its not comfortable enough. - Ewigekrieg (talk) 15:51, 3 October 2011 (UTC)

There is an ATOM feed for the changes to any page - go to the history of that page and there's a link to the ATOM syndication on the bar on the left - for this page it's this. I think if you substitute feed=rss for feed=atom in that URL that should give you RSS (but most syndication clients will take ATOM too now). 2.122.75.122 (talk) 16:25, 3 October 2011 (UTC)

Windows script

I need to rename a number (ca. 1000) of files in windows (XP). Is there a way to automate this? All files are of the form "x_y.jpeg" with "x" and "y" numbers. I want them to be renamed to "y_x.jpeg". So for instance, "1_2.jpeg" should be renamed to "2_1.jpeg", or "12_34.jpeg" should be renamed to "34_12.jpeg". Can I do this automatically in windows only or do I need to install an addition program? If so, how do I go about it? bamse (talk) 15:55, 3 October 2011 (UTC)

Here is how to do it in PowerShell

   Get-ChildItem -Path "C:\Users\Santa\Pictures\" -Filter "*.jpeg" | % {
       $file = $_
       $parts = $file.Name.Split("_")
       $new = $parts[1] + "_" + $parts[0] + $file.Extension
       $file.FullName
       Rename-Item -Path $file.FullName -NewName $new
   }

TheGrimme (talk) 17:49, 3 October 2011 (UTC)

Hugging my rename 's/(.*?)_(.*?).jpeg/\2_\1.jpeg/g' *.jpeg right about now. ¦ Reisio (talk) 18:22, 3 October 2011 (UTC)

Thanks, TheGrimme. The script returns "y.jpeg_x.jpeg" instead of "y_x.jpeg", which is irrelevant for my purpose, so no need to fix it. bamse (talk) 22:02, 3 October 2011 (UTC)

XP TO ME

Is there a program to makes Windows Xp recolonize Windows ME? — Preceding unsigned comment added by 98.71.63.46 (talk) 16:13, 3 October 2011 (UTC)

I sure hope there isn't — what do you even want it for? ¦ Reisio (talk) 18:23, 3 October 2011 (UTC)

Do you mean install over? If so, see the following page: [26].--Best Dog Ever (talk) 19:17, 3 October 2011 (UTC)

No I mean like how Vista can recolonize XP's language. — Preceding unsigned comment added by 98.71.63.46 (talk) 01:03, 4 October 2011 (UTC)

Query, what do you mean by "recolonize"? Do you mean run a program written for one operating system run under another? ie. recognize not "recolonize"? 220.101.24.249 (talk) 01:54, 4 October 2011 (UTC)

Operating systems cannot colonize or recolonize. You are obviously using a word that you don't know the definition of or you are trying to spell a word you cannot spell and typing an entirely different word. Unless you can define what you intend "recolonize" to mean, no answer can be given. If you insist on using "recolonize", it is apparent that this question is intended to be nonsense and will not be answered. -- kainaw™ 13:44, 4 October 2011 (UTC)

If you're talking about programming languages, you should know that operating systems do not have associated programming languages. (Individual compilers and libraries must support specific programming languages, but XP and ME are similar enough that pretty much anything that supports one will support the other.) Paul (Stansifer) 15:45, 4 October 2011 (UTC)

October 4

Output smartphone to monitor

Most smartphone owners want the ability to output their device display to a monitor as well as maintain their input capabilities, essentially allowing the user to "dock" with a monitor. Which smartphones allow you to do this in the easiest manner, and what's holding up wireless smartphone to monitor docking? Viriditas (talk) 03:24, 4 October 2011 (UTC)

There are a small number of Android phones that have an HDMI output. Many modern monitors and TVs will take an HDMI input. This fact is typically mentioned in Comparison_of_Android_devices, but be careful, some of them will only output hdmi in certain situations, and some of them will blank the output if you're watching a copy-protected movie. So don't base buying decisions on that list alone.

I'm not a 100% sure that "most smartphone owners" want this functionality. In my experience most people couldn't care less about this functionality. It's mostly just us developers who find it handy. APL (talk) 09:56, 4 October 2011 (UTC)

I'm fully aware of the Android functionality, but the HDMI is useless. Nobody wants that. People want wireless smartphone to monitor docking. The cloud computing model implies that devices will be used to view, not store data, which is fine when we're mobile, but when we get into a car, we want our phone to connect to the speakerphone, and when we get home, it would be convenient to dock the phone to a large monitor if needed. If you're at all familiar with human computer interaction, then you know that people interact with technology in the same way that they have relationships with their jackets, their briefcase, purses, and other possessions they lug around. People don't want multiple devices, they want one universal device that can be integrated into their daily life and interact wirelessly with other devices and technology. With the cloud computing model, this means smartphones become primarily viewing devices, with the data living in the clouds. This implies that the ultimate working and entertainment environment would be able to connect with the device to enlarge the viewing experience. Wireless smartphone to monitor docking is exactly what users want because it gives them the ultimate mobile experience. In the corporate world, this means you can go from cubicle to office to meeting room to the car and just about anywhere without having to use anything but your smartphone to facilitate data viewing. Viriditas (talk) 02:12, 5 October 2011 (UTC)

Lots of Android phones have HDMI out these days, but hardly any have 1080 lines as opposed to 720. I'm going to hold out for 1080. 71.141.89.0 (talk) 11:11, 4 October 2011 (UTC)

Agree with APL's second paragraph. Even with tablets it doesn't seem that important to most people. Nil Einne (talk) 12:51, 4 October 2011 (UTC)

I'm afraid you're wrong. Try to pay attention to how people use technology. Viriditas (talk)

I do hence why I know you're wrong, in fact you seem to have completely misunderstood what cloud computing is about. (In fact what you're suggesting seems to be the pre-cloud computing model where the phone was supposed to be the central computer because it had all the content.) In the cloud computing model the phone is just one way to access the content and apps, that's in fact one of the key points. No one wants to need their phone to view stuff on the monitor, particularly not when their phone battery life means they get perhaps 2 hours of viewing if they're lucky or they need to connect their mobile to a power source. (Even worse of course if you're using some kind of wireless 'docking' which implies the phone not only need to pointless retrieve the content from the cloud when the monitor could do that itself, their phone probably has to re-encode it to serve to the monitor. I'm presuming you do appreciate uncompressed 1080p50 needs about 2.5 Gbit/s bandwidth so serving it uncompressed wirelessly as HDMI and every other physical interconnection method does is unrealistic, you'd need to compress it in real time and worry about the sync, latency and power issues that entails.) They'd much rather their monitor has direct access to the content and apps via the cloud, with the phone completely uninvolved or at most used to control the monitor if that is needed, probably with a well designed interface intended for the purpose rather then simply a duplication of what's on the monitor. In the corporate world, this means you go to another office or a meeting room and your content is already there whether or not you have your phone, it's on, it has battery life or whatever, that's one of the key points of the cloud computing model. (Good way to impress your boss, NOT: Sorry but we need to end this meeting, my phone's battery is running low and even though my content is all on this fancy cloud you're paying for, I still can't show it to you without my phone. Even better if your phone automatically displays a text message and the whole room sees the private text message from your partner.) You may use your phone to control the content, but may be not, it depends entirely on the meeting room and what you're doing. Again, even if you do use your phone to control the content, often you will prefer a well designed interface rather then one simply duplicating what you're presenting, for example it means you can fix problems without having to show the whole room. Of course, as always, if you have any actual evidence for your claim, you're welcome to present it. But it seems it may help if you follow your own advice, the best evidence of course is ask any non-geek with a smart phone and most geeks as well and they'd think your suggestion is strange or frankly dumb. (Given how much success they've had, looking at Apple is likely a decent bet, and their cloud computing model is definitely not one where the phone is the centre of everything but rather one like I suggested where the phone is just one of the devices you can use to access your content and apps with the content and apps ideally automatically and always being there for any device.) Perhaps thinking about what you're suggesting would also help. Games and apps are one of the hot features for phones but trying to control most of these using your touch screen phone while viewing a monitor doesn't work very well. Browsing the internet using your phone works slightly better but will still often be limiting, many would much rather have a keyboard and mouse and ditch the phone completely. Ditto for composing documents etc. Really it's primarily listening to and viewing media (audio, photos and videos, personal and public) where you people may want their phones involved when they are using a monitor although again they'll often prefer a suitable interface intended for control rather then a simple duplication of what's on the monitor. Nil Einne (talk) 10:55, 5 October 2011 (UTC)

Regenerative Keyboarding

Why hasn't anyone apparently conceived of regenerative keyboarding, especially when speaking of laptops? When the energy from typing on keys gets recaptured, it goes back to the battery to recharge it (or speed along the recharging if it's plugged in.)

How would a laptop keyboard be made to recapture the energy given by the fingers clacking on the keys and give it to the battery, and why haven't such keyboards been made yet? What kinds of challenges would need to be overcome to make them? --70.179.176.157 (talk) 06:57, 4 October 2011 (UTC)

The amount of energy you could retrieve from keypresses would be so small it's difficult to see how that could power anything, let alone a laptop.--Shantavira|^{feed me} 07:20, 4 October 2011 (UTC)

Lots of people have conceived of it. Googling generating energy from keyboard returns a lot of discussion. Here is a NY Times article about Compaq patenting a method to extend battery life. But as already mentioned, you're not going to be able to power your laptop solely by keystrokes, not unless its power requirements are dramatically reduced. --Colapeninsula (talk) 10:03, 4 October 2011 (UTC)

You'd need to know a few things first:

1. How much energy could be captured from one keypress (this is probably variable depending on how difficult you want to make pressing keys to be)

2. How many key presses on average people use per hour or so (this probably varies a lot with different type of uses — browsing the internet uses very few, for example)

3. How much energy per hour the computer requires (it would be great to correlate this with the different types of uses)

The odds are that 3 dwarfs the product of 1 and 2, in the way that adding a bike pedal to a car for recharging the battery would not get you very much actual energy. The amount of watts generated by human power is generally pretty low compared to our standard level of energy consumption, as anyone who has slaved over various exercise equipment that tells you such things would know. You could try to decrease 3 by making the computer extremely energy efficient, but even then, it seems unlikely to me that key pressing would be more advantageous than, say, cranking a handle (per the OLPC XO-1), which is probably a more efficient way to transfer force than moving keys a 10th of an inch. --Mr.98 (talk) 14:05, 4 October 2011 (UTC)

On a stationary handbike, I can burn calories at a rate of roughly 30 or 40W, but it's tiring, and I probably couldn't keep going at that rate for more than 15 minutes. If the device could 100% efficiently capture that energy (which it can't), it could just about power my laptop. Typing probably takes a couple orders of magnitude less power, and people don't type continuously, so there just isn't enough energy to make an appreciable difference, even if efficiency weren't a problem. Paul (Stansifer) 14:27, 4 October 2011 (UTC)

Kinetically-regenerative phones

When users place phones in their pockets, the movements from walking and etc. would involve energy. Couldn't a kinetic energy-recapturing mechanism be miniaturized enough to be placed in phones so that their batteries can last longer (or even be recharged with more juice) thanks to this? What engineering challenges would need to be overcome in order for this regenerative system to work? --70.179.176.157 (talk) 06:57, 4 October 2011 (UTC)

Yes, you are referring to a motion-powered charger. These are still in their infancy, and the amount of energy they capture is very small, but if applied over a sustained period it could be useful. However, you would have to do an awful lot of walking to recharge a battery.--Shantavira|^{feed me} 07:31, 4 October 2011 (UTC)

For one, I think phones would have to consume a lot less energy for it to be worthwhile. Even self-winding watches will run down if you don't lead an active life, and watches take very little energy to run. APL (talk) 09:51, 4 October 2011 (UTC)

While I don't have any actual power numbers, this sort of thing is probably possible with phone technology available today- you could probably add motion charging to a proper cell phone like a Nokia 1200 to bring standby life to three weeks or a month. Switch to an e-ink screen like the Motorola FONE to save even more power, and use the latest battery technology, and maybe you'd never have to recharge if you lived an active enough life. But then you'd be looking at a price point similar to or in excess of that of a lot of flashy smartphones for something that is just an honest phone. The market for such phones among people who are actually two weeks away from a wall jack or genset just isn't that great. Nevard (talk) 23:20, 4 October 2011 (UTC)

BlackBerry not updating Facebook

My BlackBerry Bold has very suddenly stopped updating Facebook via the 'Social feeds' app – it says it's done it. It updates Twitter fine. But the Facebook posts just don't appear. I've tried logging out and in again. No luck. Can anyone advise...? ╟─TreasuryTag►voice vote─╢ 10:30, 4 October 2011 (UTC)

And the relevance this has to Wikipedia is...? (FWIW, iPhone app isn't updating either) The Rambling Man (talk) 12:41, 4 October 2011 (UTC)

It's a computing-related question - seems reasonable enough to me. AndrewWTaylor (talk) 12:48, 4 October 2011 (UTC)

Indeed ... this is the Reference Desk, not the Help Desk - questions posted here don't have to about Wikipedia. Gandalf61 (talk) 12:49, 4 October 2011 (UTC)

Working on iPhone again. What a useful thread! The Rambling Man (talk) 13:54, 4 October 2011 (UTC)

meta discussion moved to WT:RD
The following discussion has been closed. Please do not modify it.
Question: is this just a chat-board that has no relevance to Wikipedia at all, other than dubious links to, say, Facebook (although not in this case)? Presumably the aim here would be to link responses to Wikipedia articles? So questions like "my app doesn't work" surely don't belong here? The Rambling Man (talk) 16:48, 4 October 2011 (UTC) There is a link to the Ref Desk Guidelines in the header. Beyond that, any discussion should take place on the Talk page. --LarryMac | Talk 17:05, 4 October 2011 (UTC) Gotcha. So whenever an app fails to work on a Blackberry or an iPhone we should entertain a thread here. That doesn't happen too often, after all.... The Rambling Man (talk) 17:08, 4 October 2011 (UTC) What's the matter with you? This is the computing RefDesk. Furthermore, you've been told something that you're experienced enough to know anyway: that if you wish to discuss the functions and concept of the RefDesk, WT:RD is ready and waiting. This isn't the place to do it. ╟─TreasuryTag►Acting Returning Officer─╢ 17:15, 4 October 2011 (UTC) Nothing, just surprised we waste resources here by answering "why doesn't my app work?" questions which clearly have no interest in improving Wikipedia. A total waste of time. The Rambling Man (talk) 17:17, 4 October 2011 (UTC) You want me to say it again? I'll say it again. You've been told something that you're experienced enough to know anyway: that if you wish to discuss the functions and concept of the RefDesk, WT:RD is ready and waiting. This isn't the place to do it. ╟─TreasuryTag►CANUKUS─╢ 17:18, 4 October 2011 (UTC) Done already. Surprised someone with your "experience" needs to ask why a particular "app" stops working for a few hours. On the other hand, not that surprised. The Rambling Man (talk) 17:20, 4 October 2011 (UTC) I don't have to justify myself to you, particularly over such a trivial non-issue. If you aren't interested in providing helpful responses then the RefDesk probably isn't the best environment for you. ╟─TreasuryTag►Counsellor of State─╢ 17:24, 4 October 2011 (UTC) Ironic. The Rambling Man (talk) 17:30, 4 October 2011 (UTC) I wasn't "hiding my behaviour" (per your helpful edit summary), I was doing as you asked, and moving to the talk page. The Rambling Man (talk) 17:37, 4 October 2011 (UTC)

Signal boost for samsung intensity

I want to know if theres anyway i can boost my cell signal for my samsung intensity 2. I do NOT want to buy anything to do this. I have seen people boosting cell signals with wire stuck in the antenna jack but my phone does not have one. I want to know if there is some way to boost my signal strength without an antenna jack (I am somewhat okay with opening it up to do this. I unscrewed it and opened it up today but wasnt able to tell which part was the antenna.) — Preceding unsigned comment added by 99.89.176.228 (talk) 21:40, 4 October 2011 (UTC)

Since nobody else has answered, I'll suggest that as far as I know it might be possible to improve reception by lengthening the antenna (some people suggest simply inserting a USB cable in the USB socket), but not the transmission strength as this is controlled automatically. (Transmission might even be adversely affected by doing this.) If you Google "how to boost cell signal" you will find plenty of tips (some of which might void your warranty).--Shantavira|^{feed me} 16:15, 5 October 2011 (UTC)

WiFi USB 5dbi

If you compare a WiFi USB adapter (5dbi) to a normal plain laptop wifi, how much is the difference in distance? Quest09 (talk) 23:07, 4 October 2011 (UTC)

October 5

Recently I downloaded a "SystemRescueCD" (systemrescuecd-x86-2.3.1.iso) from "www.sysresccd.org/". It took several hours and about 352 Mb of bandwidth measured using a utility called NetWorx . However, when it finished saving to my HDD as a Disc Image File it was only "14.1 MB (14,876,672 bytes)". Has my download failed (seems likely) or is there another explanation for this? 220.101 talk^\Contribs(aka user:220.101.28.25) 02:09, 5 October 2011 (UTC)

md5sum systemrescuecd-x86-2.3.1.iso — if it doesn't spit out 8813aa38506f6e6be1c02e871eb898ca, then the image is no good. ¦ Reisio (talk) 11:34, 5 October 2011 (UTC)

If an A.I.'s objective is to improve itself, couldn't that speed up and spiral out of control?

Say a new supercomputer that's not built yet will have the objective to find quicker, easier and lower-cost ways to clean up the planet and bring harmony/eudaimonia to the whole human race. While on the quest to find these solutions, it's also given a secondary objective to improve itself (its algorithms, processes, hardware composition, et al.) so that it can teach/equip itself to heal humanity even faster.

Once it starts on its secondary objective, wouldn't it then gain the ability to work faster, even on its own secondary objective? Therefore, when it improves itself even faster, it not only accelerates its own self-improvement, but it accelerates the acceleration of its own self-improvement. This would be something of a recursive feedback loop.

What happens if said loop gets out of control? What is that phenomenon called, and what else will come out of this when this happens? How do we keep control of this phenomenon? --70.179.161.22 (talk) 11:55, 5 October 2011 (UTC)

We make sure we build in the Three Laws of Robotics. Mitch Ames (talk) 12:40, 5 October 2011 (UTC)

And an off switch! ;) - 220.101 talk^\Contribs 13:11, 5 October 2011 (UTC)

I think it is a legitimate concern. As far as I know nobody has ever designed a system that works that way -- it would be like having a computer that is capable of swapping boards inside its box and editing its own boot ROM: the danger of instability would be pretty high. I'm not aware of a name for that sort of instability, though -- I expect Douglas Hofstadter would call it a kindo of strange loop. Looie496 (talk) 13:46, 5 October 2011 (UTC)

See technological singularity. --Goodbye Galaxy (talk) 14:36, 5 October 2011 (UTC)

It's hard to imagine a singularity happening. After decades of research, we have not come to a good understanding of how intelligence works, and so we don't have anything like a roadmap for producing a generally intelligent program. If, after a couple of centuries, we were able to produce a program as smart as a human, it wouldn't contribute any more to the research effort than raising a kid who grows up to be an AI researcher. We would need to produce something not as smart as a human genius, but far superior to one in order for this to happen. Paul (Stansifer) 16:04, 5 October 2011 (UTC)

I'm not sure I find this a compelling line of analysis, though I am myself suspicious of Kurzweil's singularity for another reason (viz.: most exponential processes, in the real world, hit practical problems pretty quickly, and go from being a hockey-stick to being an S-curve; it's not clear to me what the "resource" would be that exponential AI growth would run out of, but there is likely something out that that would serve as a cap, in the same way that quantum mechanics threatens to eventually put a stop to a strict definition of Moore's law). I find our mere decades of research to have been pretty fruitful so far (a decade is a long time to an individual human.. but not even that long; I can still remember what I was doing a decade ago quite vividly!). And the major difference between raising an AI researching human and writing an AI program is that once you have the program, you can duplicate it with a negligible amount of additional resources. The same cannot be said for the human! --Mr.98 (talk) 16:16, 5 October 2011 (UTC)

The Science Fiction author Vernor Vinge has written several works dealing with the technological singularity, but most pertinently to the OP's query, his novel A Fire Upon the Deep explicitly portrays problems caused to advanced AIs by their exponential self-increasing intelligence, and may therefore be of interest. {The poster formerly known as 87.81.230.195} 90.193.78.36 (talk) 17:23, 5 October 2011 (UTC)

Are there any reputable, free RAM "scrubbers" out there?

They would operate like (and hopefully better than) MemTurbo except that I would like a free utility. (MemTurbo is paid.)

Since my computer seems to keep running slow no matter what I try to close, minimize, etc., I need to find a good scrubber of RAM so that after it does its work, it runs faster than before it started.

So could someone please point me in the right direction? Thanks in advance! --70.179.161.22 (talk) 13:24, 5 October 2011 (UTC)

To point you in the right direction, "scrubbing" RAM does not, and can not, improve your computer's performance. Such programs are proverbial snake oil. Ensure that you are not running any unwanted programs that consume processor and memory resources. If your computer is still running below your expectations, you probably have to upgrade to newer hardware. Nimur (talk) 13:31, 5 October 2011 (UTC)

Come back, QEMM, all is forgiven. --Tagishsimon (talk) 15:05, 5 October 2011 (UTC)