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May 9

iPad system requirements

What are the system requirements to enable an iPad to get up and running? Apple's website just says "internet access" (which I have) and "Syncing with iTunes on a Mac requires Mac: OS X v10.6.8 or later" [1]. It's that last part that worries me. Is syncing with iTunes required for the iPad to work at all? I only have an ancient PowerPC Mac running OS X 10.4. Thanks, --Viennese Waltz 13:18, 9 May 2013 (UTC)[reply]

The original iPhone, and (according to this, the original iPad) required iTunes to activate. But both that ref and this one say the newer iPads can be activated without a computer at all; but you do need a wireless network connection. Having a computer which will run iTunes does let you backup the iPad, and sync it with your existing music and movie collection. -- Finlay McWalterჷTalk 13:27, 9 May 2013 (UTC)[reply]

Great, thanks. --Viennese Waltz 13:40, 9 May 2013 (UTC)[reply]

Last year an iPad and then an iPhone both came into my possession. I activated the iPad with a Windows PC, then the iPhone I just used my WiFi to do it on the phone. Since then I've synced each with the PC about 3 times, and won't be bothering again. Any important documents and files are in the cloud, either through Apple iCloud, Dropbox, Google Drive, my work's email server or my own NAS drive. So, to answer your question, as Finlay says: no system is required, for activation or for general use, other than an internet connection. - Cucumber Mike (talk) 13:45, 9 May 2013 (UTC)[reply]

Checking grammar

Replaced to Language helpdesk --Larsnl (talk) 15:54, 9 May 2013 (UTC)[reply]

street fighter II for the mega drive

Hey, so, I got a sega mega drive (genesis) emmulator, and I got Street fighter II, reason is well partly because there is a street fighter ii machin that I found in an arcade and I wanna get super good before I challenge french Bobby at it, but also cause I figure it'd be good kicks whilst back here at Maison Snicks so basically I can't play two player just using my keyboard, it's clear insanity you need six buttons plus arrow keys, etc, so is there a way to either A) hook another keyboard up so someone else can play or B) plugging in two sega megadrive controlles into a PC? Any tips greatfully required - thanks all! Horatio Snickers (talk) 21:43, 9 May 2013 (UTC)[reply]

Which Megadrive/Genesis emulator are you using? Kega Fusion (the only one I've ever used...) apparently supports USB controllers though I'm not sure about actual Megadrive ones. You'd have to mod the cable to be USB, which I've seen done with NES controllers before so it probably is possible; though probably too much work. Having one player use a keyboard and another use a controller or both use controllers should work with that emulator. Good luck! --Yellow1996 (talk) 23:16, 9 May 2013 (UTC)[reply]

A) In Windows, you can connect multiple keyboards, just plug another keyboard into an available USB port on your computer. However, all the keyboards are merged together logically. Windows can't tell the "A" key on keyboard 1 is different from the "A" key on keyboard 2. So you'd still have to make sure the player 1 and player 2 keys are different, but maybe plugging in another keyboard might give two players a little more space (instead of trying to crowd around one shared keyboard).

B) You can find cables that have Genesis controller ports on one end and a USB cable on the other end. Do a Google search for Genesis USB. Look in your emulator's settings to make sure it supports controllers and lets you set up the buttons. --Bavi H (talk) 02:57, 10 May 2013 (UTC)[reply]

If the software doesn't support conrtollers natively, there's a program you can get (I think called Joy2Key, but I'm at work so can't check) which will map the controller inputs to keystrokes so that you can use normal keyboard bindings. MChesterMC (talk) 08:36, 10 May 2013 (UTC)[reply]

May 10

MP4

Windows Media Player won't let me play .mp4 files! So, does anyone know where I can download the codec needed to play my files on WMP? (I have Winamp as well but WMP is my preference ...) And one more thing: I don't want to download a giant codec package, only the one necessary for what I'm doing. Thanks! --Yellow1996 (talk) 00:10, 10 May 2013 (UTC)[reply]

".mp4" is a file extension, and by itself conveys no information. It usually implies that the file conforms to the MPEG 4 container format. Even that still isn't enough information to determine the codec of the file. (Often, the file extension additionally implies that the codec is MPEG 4 Part 10, or, "H.264" - but this is not universally true).

In my experience, I have found ffdshow (a Windows DirectShow plug-in for ffmpeg) to be the best all-around way to get most video files to play on Windows. It is a port of libavcodec, a free and open source library that implements the H.264 standard, as well as other common standard codecs. Nimur (talk) 01:42, 10 May 2013 (UTC)[reply]

I’d go with VLC media player if I were stuck on Windows. ¦ Reisio (talk) 07:03, 10 May 2013 (UTC)[reply]

Seconded. However, VLC does seem to have trouble with some files that the native Windows Media Player seems able to handle. I don't know if it's caused by improper coding or oddball codecs, but I keep both programs on hand for use; I can't trust either one 100%. 64.235.97.146 (talk) 19:58, 10 May 2013 (UTC)[reply]

Problem solved. Thanks, everyone! :) --Yellow1996 (talk) 01:46, 11 May 2013 (UTC)[reply]

RetroUI problems

I've been having a problem since I added RetroUI to my Windows 8 computer (I'm 5 days into the 7-day trial). After I boot, after the desktop appears, it takes a long time until I can use the computer. The mouse is not there, etc. The amount of time from when the desktop appears until I get control of the computer varies a lot, but I've measured it at up to 110 seconds. The RetroUI tech support thought that something was keeping it from starting. I'm using Avast and Malware Bytes, and I added everything in the RetroUI folder to the exclusion lists, and I still have the problem.

Does anyone have an idea about how to fix this? Bubba73 ^{You talkin' to me?} 05:38, 10 May 2013 (UTC)[reply]

Uninstall it and switch to Classic Shell; or better yet, switch to an altogether more sane OS. ¦ Reisio (talk) 07:01, 10 May 2013 (UTC)[reply]

I had been using Classic Shell before RetroUI. I think RetroUI is better, excpt for this startup problem. Bubba73 ^{You talkin' to me?} 14:59, 10 May 2013 (UTC)[reply]

One thing to be aware of with programs like RetroUI is that a lot of what they are doing is not based on any of the publicly documented APIs supported by Microsoft. This means that they're probably based on experimentation and assumptions of how things work in the OS rather than official facts stated by Microsoft. This can lead to unusual and hard-to-reproduce bugs when the software is run in the unique environment of systems other than the ones it was developed on. Microsoft is planning on releasing an update to Windows 8 before the end of the year that they claim will address a lot of the complaints. If you're still not happy with it then, there is always the option of downgrading to Windows 7. Right now it is selling for about $90 on Amazon in the US - a lot more than the $5 for RetroUI, but it also gets you back to the proper version of the interface RetroUI is trying to reproduce. 38.111.64.107 (talk) 18:59, 10 May 2013 (UTC)[reply]

I upgraded this computer from Win 7 to Win 8. I had the option of going back, but I decided not to. Bubba73 ^{You talkin' to me?} 23:56, 10 May 2013 (UTC)[reply]

Is there any good, easy way to do nominally GUI-oriented stuff in Windows?

I was surprised to find out that Ruby uses Tcl/Tk to do Windows GUI stuff. Why is a fancy language like this that aspires to have everything predefined by convention not offering its own simple set of commands to interface with the OS directly? More to the point, are there easy options in other languages (Lua, Perl) for basic navigation? For example:

I want to drag a file and drop it on some icon and have my script run, and have it receive as parameter(s) the name and location of the file dragged onto it.

I want to have an icon for Command that I can copy into that directory that opens in that directory, no CD required.

I want to have a function as simple to use as print() for a Lua program that can take a string of text and uses it to display/conceal/resize windows or add buttons, content, etc. into them as simply as you'd add a return with "/n".

Am I just clueless about options for stuff like this, or is there some huge cluster fuck in windows that is preventing people from making basic stuff like this, or has no programmer ever seen a need for any of these things? Wnt (talk) 13:03, 10 May 2013 (UTC)[reply]

I really don't understand your question at all. If you're asking "why does Ruby use a clunky old thing like Tk rather than Windows' own GUI framework", well I think that's because with Tk is particularly easy to get something basic working with just a few commands. The real Windows GUI is available to all programs, and all programming languages, from DLL files. It's certainly possible to write old-style win32 GUI programs in other languages (I've done this with win32gui in Python), but that's a tiresomely low-level API, so writing programs is a bit of a chore. Programs can also use higher level (which can mean less flexible) frameworks like WinForms (I've got a python program somewhere that does that too). These, and other APIs like Direct X are available to everyone - as a practical matter, someone usually has to write a little translation shim that bridges the gap between that language's data model and the native API (which are usually exported by DLLs using Microsoft's own x86 calling conventions). Other programs (e.g. Wireshark, Audacity) eschew the native API (which, after all, confines them to running only on Windows) and use cross-platform GUI toolkits like Swing (for Java), GTK, Qt, Tk, or WxWindows - these allow the same program to be compiled, with little change, on Windows, MacOS, Linux, etc. - at the expense of the resulting program looking slightly alien on every platform. But if your question really is just "GUI programming seems unduly complicated, tiresome, and obscurant", then yes, it is. GUIs are powerful, complex, concurrent, asynchronous, and graphical, so it's inevitable that programming one is going to be much harder than a simple interrogative textual Q&A. -- Finlay McWalterჷTalk 14:16, 10 May 2013 (UTC)[reply]

I'm getting the point that Tcl/Tk (and others) give a platform-independent GUI, but I still don't really understand why other languages wouldn't include these features directly, in an equally platform-independent way, and hopefully invent some new philosophies about how to make them better. Wnt (talk) 19:48, 10 May 2013 (UTC)[reply]

Tcl is beside the point - Ruby does not use Tcl. Ruby uses Tk, but can use other GUI frameworks too, and other languages can use Tk. You should not impute a particular preference in Ruby for Tk - its bundling is just a matter of convenience. Languages have to do lots of different things, and reimplementing their own way of doing everything, rather than using what's available on the system already, is often foolishness. GUIs are no different - language developers have enough work to do just developing their language and the core stuff that they can't get elsewhere. So they use existing GUI frameworks, either platform specific or multi-platform, to get stuff done. Strong coupling between a language and a GUI framework is usually a way to make a weak language and a weak GUI. Sometimes, as with Java's AWT or Swing, language developers have reluctantly had to also develop a GUI in parallel (particularly back in the 1990s when AWT and Swing were born), often because there wasn't a suitable multiplatform GUI that met their requirements. These days GTK and Qt in particular are very mature, and it is difficult to see why some language should reinvent those very fine wheels. Don't think that including stuff into a language "directly" is a good thing; it is usually not, and wise language designers try to keep their languages as small, and as task-directed, as possible. -- Finlay McWalterჷTalk 20:17, 10 May 2013 (UTC)[reply]

Possibly the easiest (and thus least flexible) way of doing very basic GUI tasks is Zenity which allows shell scripts to do some very basic dialog box ("do you want to wipe the disk?") type things. The practical utility of this on Windows is somewhat questionable - it does allow cmd.exe scripts some semblance of a a GUI, but working in that antediluvian horror is such a bother that GUIs are the least of someone's worries. Once someone migrated to Windows Powershell, which passes for a sane, modern shell, they get direct access to DLLs, and might as well just make Winforms calls like this. -- Finlay McWalterჷTalk 14:39, 10 May 2013 (UTC)[reply]

bokeh enhancement

artificial bokeh where there isn't any is probably the worst thing ever, say you have an image with bokeh and existing blur. Is there an algorithm to detect how blurred a part of an image is, and based on that, add existing blur? Can you turn an 85 f/2.8 image to an 85 f/1.4 image for instance? 137.54.31.42 (talk) 14:18, 10 May 2013 (UTC)[reply]

There is no such thing as "I' am aware of artificial bokeh" when it depends on your lens. You, as a photographer have full control - if you know how. Can you turn an 85 f/2.8 image to an 85 f/1.4 image for instance? No. --Aspro (talk) 18:08, 10 May 2013 (UTC)[reply]

Bokeh can be modeled as a point spread function whose parameters depend on distance to the camera aperture. You can in principle create an estimation algorithm to determine depth, and calculate an appropriate point-spread for that point, and then convolve the PSF with your input image. If you've followed the details, you will recognize this as an adaptive nonlinear filter; in other words, for a seemingly-simple task, you will need to run right up against the state-of-the-art in the mathematical theory and practice of signal processing.

Keep in mind that when you change the aperture size, you are not only changing depth of field (and therefore, the magnitude of the visual appearance of the bokeh); but you are also changing the total light collected; the focal properties of the lens; and you are potentially exposing more imperfections of the image-capture system. It is not sufficient to model the change in the PSF alone.

Here's a fun slide-deck from a 2008 conference, Modeling and Synthesis of Aperture Effects in Cameras. Nimur (talk) 18:23, 10 May 2013 (UTC)[reply]

what is innermetrix?

I just found innermetrix on my computer. What is it? Where did it come from and How did it get on my computer? How do I remove it?173.21.123.164 (talk) 17:44, 10 May 2013 (UTC)[reply]

Innermetrix is a firm of management consultants, and I can't find any other references to the word immediately. Are you sure that's the right spelling? Tevildo (talk) 18:33, 10 May 2013 (UTC)[reply]

Yeah I also did a search with different keywords and only turned up that site. Is it a program? Where did you find it? --Yellow1996 (talk) 02:47, 11 May 2013 (UTC)[reply]

May 11

Desktop backgrounds...(A more convenient way to switch them?)

Let's say I have a picture of oh...how about a generic landscape - in the daytime. Now let's say I have a picture of the same landscape, but at night-time. Is it possible to somehow make a keystroke combination so I could toggle between the two, without having to keep right-clicking and choosing "set as desktop background..."? This would be quite useful if I had a few different pictures I wanted to constantly switch between. Is this possible, with two, three, or many? Thanks! --Yellow1996 (talk) 02:42, 11 May 2013 (UTC)[reply]

On Linux, you could use nitrogen or feh to show a wallpaper, and set up a script with hotkeys to switch them. On Mac, the answer is almost certainly yes--there seem to be plenty of wallpaper managers which could be controlled in the same way. Anything else, and you're on your own. Henry ^Flower 15:33, 11 May 2013 (UTC)[reply]

Windows 7/8 does it automatically: http://windows.microsoft.com/en-ie/windows7/create-a-desktop-background-slide-show. - Cucumber Mike (talk) 16:09, 11 May 2013 (UTC)[reply]

Oh sorry guys, I forgot to mention I'm on Windows Vista. Is it possible on that OS? --Yellow1996 (talk) 19:00, 11 May 2013 (UTC)[reply]

If you don't wish to use a program designed specifically for this function, you can set a scheduled task to do it. Follow the instructions in part two of the first answer to this superuser question to create a vbscript to change the wallpaper based on the time. Now open task scheduler, and schedule this task to be run at the appropriate times. You'll also want it to be run shortly after logon to set the wallpaper when you turn on your computer. ⚠Efreak 09:58, 14 May 2013 (UTC)[reply]

Looks cool...but is there a way I could modify the code to make the wallpapers change with a keystroke combination rather than on a timer? --Yellow1996 (talk) 23:36, 14 May 2013 (UTC)[reply]

slow boot

This is related to the "RetroUI problem" above. I'm using Windows 8. I was using RetroUI, but after the desktop came up, it took about 110 seconds for RetroUI to load. Until then, the mouse cursor did not appear on the desktop.

Now I've removed RetroUI, but I have somewhat the same problem. Now after the desktop does appear, the mouse cursor shows up. However, no apps that I click on will come up. I can click on Computer, explore a drive, click on a batch file on the desktop, and do ctrl-alt-del. But nothing else works for 100-110 seconds after I get to the desktop, when my gadget appears and the rest of the icons appear on the taskbar. Then everything works. (Until this time the only two icons that appear are the "safely remove" and Malwarebytes.)

Any ideas of how to fix this? Bubba73 ^{You talkin' to me?} 04:17, 11 May 2013 (UTC)[reply]

It's possible that RetroUI wasn't completely removed from your system. Did you delete all the folders manually, or did you go to uninstall/remove programs? If you did the latter, search around and see if there is anything left over. I don't have experience with that particular software, but this has happened to me many times with other things and is quite a bother. If that doesn't work then I'd do a full computer scan. Good luck! --Yellow1996 (talk) 19:11, 11 May 2013 (UTC)[reply]

I did the regular uninstall in the control panel. I'm not sure if this was caused by RetroUI. I do a full virus scan each week and a full malware scan each week, with quick scans each day. I'll try a full scan. Bubba73 ^{You talkin' to me?} 23:31, 11 May 2013 (UTC)[reply]

The retroUI folder was still there, but I don't know if that was causing the problem. Anyhow, I deleted it. Bubba73 ^{You talkin' to me?} 23:58, 11 May 2013 (UTC)[reply]

In that case, I doubt it's a virus - this was probably all caused by RetroUI. Deleting the folder was a good idea; that could have been the issue. Does the problem persist after you deleted it? --Yellow1996 (talk) 17:37, 12 May 2013 (UTC)[reply]

I haven't booted again since I removed the folder. I ran both complete scans last night, but they found nothing. Bubba73 ^{You talkin' to me?} 21:54, 12 May 2013 (UTC)[reply]

Well at least we know it wasn't a virus at work there. But next time you're on the system in question see if the problem still exists - and hopefully it doesn't. --Yellow1996 (talk) 01:32, 13 May 2013 (UTC)[reply]

I'm back to using Classic Shell. It still takes a long time for the weather gadget and most of the icons to come up, plus a long time before IE will start. Bus some other programs will come up not too long after the desktop is visible - e.g. EditPad, Word, Thunderbird, and Firefox. I had been testing with IE because if the internet is down, it realizes it quicker and handles it more smoothly than Firefox. So maybe it is just taking a long time to boot. (It takes a long time with the dots are spinning too.) Bubba73 ^{You talkin' to me?} 02:24, 13 May 2013 (UTC)[reply]

Hmmm... that's quite puzzling. And this all started when you were trying out RetroUI? Switching back to Classic Shell was a good idea but I wonder why it's still so sluggish to boot. Perhaps registry errors? Fragmentation? Junk files? I'm just guessing, but those types of things could be causing you trouble...do you run fixer tools for stuff like that often? --Yellow1996 (talk) 16:21, 13 May 2013 (UTC)[reply]

Well, I'm not sure if it all started with the RetroUI trial. But one part certainly did - the mouse used to be usable right after I got to the desktop. With RetroUI, after I saw the desktop, the mouse cursor did not appear until RetroUI loaded, which was 100-110 seconds after the desktop came up. With RetroUI removed, the mouse comes up when the desktop does, but only some things will work when clicked on. For instance, if I click on IE nothing happens until it finishes the entire boot process (the rest of the icons appear in the tray and the weather gadget comes up) - then IE starts. I estimate that the entire boot process takes nearly 10 minutes, and this is a quad-core i7 with a 7200 RPM drive. I clean out junk files from time to time but I don't do registry cleanup anymore because I read that they really don't help much. Bubba73 ^{You talkin' to me?} 16:33, 13 May 2013 (UTC)[reply]

Okay, that definitely should not be happening on an i7. So if there already were problems before, they could have just gotten worse coincidentally when you were trying out RetroUI - while that software itself only caused your mouse troubles - therefore misleading us as to what the real problem is. If this is really annoying you/hindering stuff you are doing on the computer I would just take it in to a specialist to see if they can figure it out...though that can be expensive! --Yellow1996 (talk) 16:44, 13 May 2013 (UTC)[reply]

This computer came with Windows 7, upgraded to Windows 8. I didn't time it, but W8 seemed to boot faster than W7 - used to at least. I just rebooted and timed it (min:sec - elapsed time from restart).

0:00 restarting

0:45 blank screen

0:55 blue window logo, spinning dots

3:35 blue welcome screen, sound

3:50 desktop appears

6:25 completely finished booting

I didn't touch it in the process. Bubba73 ^{You talkin' to me?} 16:50, 13 May 2013 (UTC)[reply]

Wow. So the slowdown is definitely on the desktop! So does the computer have the same speed as before while you are doing things like browsing the internet and running programs (is the slowdown only in the booting process)? --Yellow1996 (talk) 16:57, 13 May 2013 (UTC)[reply]

I had something similar on a PC running XP. When I got it, it would be workable quickly. Subsequently it spent a long time on the "Loading Windows" or somesuch. I eventually traced it to having turned off bluetooth. It was obviously timing out trying to find it. Turn it back on and all was well. Could it be something similar? --Phil Holmes (talk) 17:03, 13 May 2013 (UTC)[reply]

Generally, after it finishes booting it seems OK. There are two little things compared to the way it was a couple of months ago: (1) every few minutes there are burps when playing back a sound file - itunes or YouTube, (2) every once in a while (maybe a few times per day), while typing, the letters I'm typing don't appear right away, but after a few seconds they suddenly appear. Bubba73 ^{You talkin' to me?} 17:09, 13 May 2013 (UTC)[reply]

Hmmm...your second thing happens to me sometimes as well; though that's to be expected from a 5-year-old laptop running Vista. I'd say my above advice to take it in if this is an urgent problem for you is what I'll stay on. --Yellow1996 (talk) 17:15, 13 May 2013 (UTC)[reply]

Have you checked what is running at start-up? I believe they moved the interface for that into the task manager, or you can probably find it by searching for startup. I would also check through the device manager and see if there is anything unusual - I don't know how RetroUI does its magic, but it is plausible that there could be a driver running in the background to help it out, and maybe it didn't uninstall properly, although I suspect that it would cause problems earlier in startup. You could also check the list of running services and see if any are related to RetroUI or other third-party software you have installed. 38.111.64.107 (talk) 11:45, 14 May 2013 (UTC)[reply]

I have several things starting up, but the Task Manager doesn't show anything for RetroUI - either running or in the startup list. Bubba73 ^{You talkin' to me?} 00:43, 17 May 2013 (UTC)[reply]

You can try searching your registry for any references to RetroUI. If nothing else works, you can refresh your PC: Windows 8 Tip: Reset or Refresh Your PC. A Quest For Knowledge (talk) 18:15, 17 May 2013 (UTC)[reply]

PHP geolocation consent on smartphones

In the hypothetical scenario where a friend's phone was stolen, would it be possible to send to that phone (via SMS or Whatsapp) a link to a webpage that geolocates the client, and if the thief clicked the link, the page could locate the phone without any other consent? Or would they get a popup saying something like "Do you want to share your location with [webpage]?" --Markr4 (talk) 09:32, 11 May 2013 (UTC)[reply]

It’s been a while since I looked into it, but IIRC you can do a number of things if GPS was left on or if you had preinstalled an application designed to deal with this type of situation. If your friend’s phone was stolen and it has any personal information on it and no locking mechanism (screen lock, password, etc.) whatsoever, the first thing you should do is call your provider and have them brick it. No phone is worth criminals having access to the kinds of information stored on them. ¦ Reisio (talk) 10:28, 11 May 2013 (UTC)[reply]

I don't really understand the suggestion here. In most places and countries, the most your provider can do if you report your phone as stolen is add the IMEI to a black list. (In some countries like the US, it's commonly said that the phone is bricked, but this seems unnecessary confusing in the context, even more so with smart phones where there's a lot you can do with the phone even if it no longer works with mobile networks.) In a number of countries these black lists are shared with all local providers. There have even been some attempts to develop shared international black lists, although I'm not sure how far these have got. Either way though, these stop criminals using the specific phone on mobile networks which is intended to discourage theft (although there's still the problem of people changing the IMEI), but don't achieve much else.

In particular they will not generally protect your personal information. If the information is stored on the phone, the fact that the phone is blacklisted is of no consequence since the information is still stored on the phone. A smart thief intent on stealing the info would likely disconnect the phone from all networks from the moment they can do so (to prevent tracking and also to reduce the possibility of an app activated remotely doing stuff) and then use forensic tools to backup all data from the phone and analyse it from there so the IMEI being black list is of no consequence, they won't even know it happened. A dumber thief may use the phone until it now longer works, and then try to recover the data, if they're careless they may have already killed some of it, but most of it will still be there.

For information stored remotely (i.e. in the cloud) but for which the password or some access code is stored, it's more complicated, but the phone being blacklist would not generally help much unless the service is intrinsically tied to the device which isn't very common. For such information, the more important thing to do would be to change the passwords for all these services. This would generally get round the problem of compromised passwords, and many services also kill all cookies and similar tokens when you change your password (unfortunately not all).

I'm not saying you shouldn't report your phone as stolen, a more important reason is not to blacklist the phone stolen, but ensure the mobile provider deregister or block the specific SIM card or connection between the phone and your mobile account. (I think you could normally tell the provider whether you want the IMEI blacklisted or not, so you're not forced to do both at the same time, but I'm not sure.) This stops them using services you may have to pay for and more importantly stops them spoofing you which can be important nowadays with the way some services including banks sending passwords or tokens to mobile phones. (It would also stop them trying to scam or just plain annoy your friends and relatives.)

Note however this could also be counter productive if you do have a lot of valuable information stored on the phone. As mentioned below, iPhone has a phone locator service. The Google Play store on Android phones generally allows remote authentication for the installation of apps (you choose to install the app on a browser while logged on and when the phone has network access it will download and install the app), so you can install either a locator app or a data deletion app. As most criminals don't really know what they're doing, quite a few will give the phone mobile network access (if you haven't disabled it, just turning on your phone or leaving it on will usually be enough if they don't do anything) enabling you to run these apps to either delete data (in the case of Android) or locate the phone and attempt recovery. Having it black listed will not generally stop it being used with wifi, but it may discourage the thief from using it.

Ultimately you'll have to make the choice between different factors at play. It may be that your network would be willing to partially block a phone or limit the ability of the thief to use services to ensure they don't spend too much money. In addition, you could disassociate the phone number from anyone services which may send passwords or tokens to it (in some cases this may result in a SMS notification being sent to your phone, but perhaps you can stop that if you report the reason is because of theft).

Nil Einne (talk) 03:34, 12 May 2013 (UTC)[reply]

For the iPhone there's Find My iPhone, which can also remotely lock the device. AndrewWTaylor (talk) 13:26, 11 May 2013 (UTC)[reply]

Whether a web page can see your location without asking permission is up to the browser. You could visit the web page beforehand and permanently approve it to see your location, but your scheme still requires a pretty dumb thief to work. I have no idea what percentage of thieves are that dumb.

There are apps that will autoreply with the phone's location to an SMS message containing a preset phrase, such as this one for Android. -- BenRG 07:22, 12 May 2013 (UTC)

GMAIL SETTINGS

I use Gmail.

How can I set the emails from unknown sources, received in the spam folder instead of inbox folder?
How can I block bogus/unwanted emails, not even received in the spam folder at all?
Even thought I requested, I don’t receive email updates from some blogs/web pages. How can I receive those email updates?

Please help me to solve the above problems. It may be due to that I am not familiar with the technical terms. Thank you.175.157.181.240 (talk) 10:22, 11 May 2013 (UTC)[reply]

Gmail has some kind of an automatic spam filter, although you can filter specific emails to automatically go to spam based on the sender. Some websites like Wikipedia itself have an option to turn on emails, but it varies by blog/website. Numbermaniac - T - C 10:26, 11 May 2013 (UTC)[reply]

May 12

May 13

E top-up and e-vouchers in the UK

How are E top-up cards and e-vouchers used in the United Kingdom for topping up mobile phone SIM card accounts?

I was not sure whether to ask this here or at the humanities reference desk (as it concerns finance), please move as necessary.

While looking for a Pay as You Go SIM card for use both in the UK and while roaming, I noticed the methods of topping up were quite limited (I am used to European SIM cards where I can top up at any TABAC or online with any credit card). Also, I had hoped that wikipedia would have had an article on the term E Top -up which is quite new to me. The related term e-voucher is also a redlink - the section in ORCA card appears specific to Washington State, USA.

Some websites partly explain the concept: [2], and [3]; but I was looking for how an E Top-up card is obtained and used by the end-user, and more background on the term and possible synonyms (for example "TopUp swipe card" from Vodafone sites). Ideally I would like to see a video of someone obtaining and using such a card with an ordnary non-smart mobile phone, or online in a browser.

I don't know the specifics of the system in the UK, but AFAIK in most places where such systems are used, they basically involve the person paying money (cash or possibly debit or even credit cards depending on what the norm in the local country and other factors) to whatever store offers the topup/reload vouchers, the store then entering the amount and the machine (in some cases it may be tied to the cashier machine) then prints the voucher with a unique number. The person can then either call a generally free number on their phone, follow the prompts (e.g. push 1 to topup, push 1 if you are using a topup voucher, enter the number and then press the hash key) and when down the system will likely tell them if their topup was successful, how much the topup was and what their current balance is (You successfully topped up your account with 20 dollars/pounds/whatever. You new balance is 44.96 dollars/pounds/whatever.) Alternative they can sent the topup number to a special SMS number and they will receive a reply telling them something similar to the voice service. I'm not sure that many bother with using online services for such vouchers but if they are possible, they would like involve logging on to your account and then selecting the topup with voucher option and entering the number. I'm not sure if it's common that you can topup other numbers with such vouchers although it may be possible if the voucher topup works exactly the same as with credit card etc. I think in most countries, normally people will just send the number by SMS if they want to gift someone a topup with a voucher, or give it in person.

In some cases you may also be able to buy the vouchers from vending machines, but particularly if vending machines accept credit or debit cards or something else which requires a network connection they may just ask you to enter the mobile number and then they tell the service to topup your number so you don't receive anything other than perhaps a receipt and an SMS when the topup has succeeded. Similar to the way ATM topups usually work AFAIK (although commonly you may also be able to tie a number to your ATM).

I'm not sure whether evoucher systems need a network connection. I originally thought they did since they got the unique topup number from the provider but on further consideration I think I'm mistaken, likely the machines can generate the number themselves and use a unique seed so the provider knows who it's from. (There will be some complexity in balancing the accounts since the machine and retailer will count the moment the voucher is produced, the provider only knows when it's used.) If they do and the machine only accepts cash, then perhaps it will have traditional topup vouchers so no network connection is needed but otherwise evoucher is a lot simpler since they only need electricity and someone to collect the cash every so often rather then also reloading the cards. It could of course be that both are in play depending on the country and provider or the machine can generate the numbers but does need regular reconciliation with the provider to reduce confusion from purchased but unused vouchers.

The top-up swipe card you refer to in the UK appears to be different from a voucher, from the description on the Vodafone site it sounds like you have a swipe card linked to your account which the retailer swipes to send the topup directly to your account so there's no voucher involved. Such a system definitely requires a network connection.

BTW, I'm pretty sure the evoucher is just a slightly modified version of the older system probably common in most countries (including Europe) where prepaid services were common using cards (vouchers) generally of the 'scratch and win' type (to ensure the card hasn't already been used before purchase) which is probably still somewhat common in some countries.

The advantage of the electronic system is you remove the need to keep any stock on hand of cards and all the problems associated thereof of needing to store, restock and manage stock levels to ensure you don't have too many or too few or they are lost or stolen, you may also be able to offer more values although I think many systems still only allow a small range of values for evouchers (i.e. you can't topup $24.53 and probably not even 24), however the range could be larger. From the providers POV, they don't have to produce the reload cards using reasonably high security systems (i.e. costly). Also for big retailers, they may let them tie it in to their checkout system so there's no need for separate machines or receipts. It also likely makes some degree of tracking easier since someone (as per my earlier comments on the network connection, it could be the provider, more likely the retailer or the machine) may keep records of precisely when the topup was purchased and the provider may keep records of what number if was used to reload. (And if they do use a unique seed, the provider can then ask or tell interested parties the retailer who has that seed for their records.) Besides the obvious and perhaps controversial use when the police are trying to track a mobile phone or tie it to a person, it would likely be useful in the even of disputes.

The main disadvantage compared to traditional cards is the cost of the machines (including maintenance etc) to generate the vouchers which someone has to pay (if the retailer integrates it in to their system then there's the cost of the integration). The machines at a minimum will also need electricity and likely the occasional refill of thermal paper. The machine will also likely take up more room in an accessible location (depending on the number on hand, the stock of cards may take up more room overall but these can be mostly stored elsewhere). And while you could print the vouchers and take them around, this would require a greater degree if trust compared to unscratched cards. Presuming they don't need a network connection or regular reconciliation with the provider, I suspect that vouchers from machines also have shorted expiry dates then cards (which could potentially never expire) to reduce the confusion from purchased and unused vouchers (particularly in the case of theft or alleged theft of the machine). And of course under either scenario, you may have to pay for the voucher the moment you print it out whereas I'm not so sure with cards and either way the retailer could likely return them unscratched and effectively not pay.

Either way, such vouchers do add cost but the overall advantage is that there's no need for credit cards or ATM cards or online banking or debit authorisation which not everyone may have or trust (in developing countries or 15 years ago even less so) which are usually required for alternative systems. And debit authorisation without online banking or similar is a complexity people may not want to deal with.

Note that if a network connection is available, instead of vouchers they could use a system whereby you enter your phone number similar to the way you do with ATMs and possibly some vending machines, that adds time while the checkout operator is waiting (even more so if the machine asks for it twice to reduce the possibility of errors) and considering some people don't know their number off hand and people may also be reluctant to enter their numbers if the retailer can see it. (The system used by Vodafone in the UK with swipe cards eliminates both problems.) It may be in some countries (and this would also apply to vending machines) that the voucher is familiar enough that most people prefer it even if there's no reason they couldn't just use an enter your number system. One obvious advantage of the voucher system is you can keep the number and not use it but have it on hand if it's ever needed (probably stored in your phone, particularly if it was printed on thermal paper), e.g. as a way of controlling usage. It also allows a simple networking based method of almost instant topups and credit where if a friend or someone who trusts you sells such vouchers you can SMS them and they can send you a voucher in reply and you can settle the transaction later. (They could also use send the topup directly to your phone but that would require them to have a network connection and even if they have a smart phone I don't think all providers make their commercial topup sites free. While they have to have the vouchers stored in their phone, once that's done there's a fair chance it'll also be faster to just send you a voucher then enter your number in to a topup site.)

One interesting point is that in some countries where provider enforcement of exact pricing is limited, you can sometimes purchase such vouchers (whether the cards or the evouchers) for slightly less than the face/topup value from certain retailers or perhaps from forums or other places. Although the amount saved is small since they don't actually earn much per transaction. (This can also happen with topup your phone directly systems, particularly if they allow value transfer cheaply and there's significant advantages to big topups.)

Nil Einne (talk) 04:27, 13 May 2013 (UTC)[reply]

Pioneer DDJ Ergo?

What's the difference between DDJ Ergo-V & DDJ Ergo-K? Which is better? 220.233.20.37 (talk) 08:47, 13 May 2013 (UTC)[reply]

The Ergo-V is given a 4.5/5 here but a 3.5/5 here. The Ergo-K has an average rating of 4/5 (based on 19 ratings) here. As for which is better, you should read through those pages and make the decision for yourself; as you probably know exactly what you want to get out of it. --Yellow1996 (talk) 16:31, 13 May 2013 (UTC)[reply]

GIF images/IE9 Favorites

This time, I've got two questions: 1) Why do some GIFs load in your default Internet browser rather than the usual picture-viewing interface? Is there a way to change this? 2) Is it possible - in IE9 - to check and see when you added a certain webpage to your favorites? Thanks! --Yellow1996 (talk) 16:15, 13 May 2013 (UTC)[reply]

Files do not load themselves; a user interacts with a user interface, causing the operating system to either directly or indirectly launch a computer program that loads the file. You may find our article on file association helpful. If you are using Windows, you may adjust settings using the default programs control-panel interface. Nimur (talk) 17:27, 13 May 2013 (UTC)[reply]

I tried to right-click and open the GIF file in Windows Live Photo Gallery (what I usually use) but it says that "Photo Gallery can't open this photo or video. The file may be unsupported, damaged or corrupted." - I'm fine viewing them in IE, it was just a curiosity question; but thank you anyway! :) also, does anyone know if my second scenario is possible? --Yellow1996 (talk) 17:36, 13 May 2013 (UTC)[reply]

If you're using Windows 7, this may help you. -- 140.202.10.130 (talk) 20:28, 13 May 2013 (UTC)[reply]

I'm actually on Vista - sorry (I really need to start specifying this.) But thank you for finding that info for me anyway. Like I said before, it's no big deal; I can view them in IE no problem. :) --Yellow1996 (talk) 01:24, 14 May 2013 (UTC)[reply]

I was assigned to write a program that resembles a "menu" in that there are a set of rectangles that change color when using arrow keys. There are two problems with my program and I can't figure out why:

Indented line

1. even though I used the "readkey" line twice (by writing "ch:= readkey; if ord(ch)=0 {or keypressed} then ch:= readkey" I still have to press arrow keys twice to make it work.

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2. When going from the first item of the "menu" to the last one by pressing the "↑" key, the first item remains colored although there's a "cleardevice" command at the beginning of the loop.

here's the (main part of the) program

initgraph(gd,gm,);
setbkcolor(0);
setcolor(10);
rectangle(200,100,400,400);
readln(n);
d:=300 div n;
for i:=0 to n-1 do rectangle(200,100+d*i,400,100+(i+1)*d);
y:=100+(d div 2);
floodfil(300,y,10);
Repeat
Begin
ch:=readkey;
if ord(ch)=0 then ch:=readkey;
cleardevice;
for i:=0 to n-1 do rectangle(200,100+d*i,400,100+(i+1)*d);
If ord(ch)=72 then if y-(d div2)>100 then y:=y-(d div 2) else y:=100+n*d-(d div 2);
If ord(ch)=80 then if y+(d div2)<400 then y:=y+(d div 2) else y:=100+(d div 2);
setcolor(10);
floodfill(300,y,10);
delay(60);
End;
until ord(ch)=27;
readln;
closegraph;

--Irrational number (talk) 21:58, 13 May 2013 (UTC)[reply]

I've added source-code formatting to your code for improved readability. Nimur (talk) 22:05, 13 May 2013 (UTC)[reply]

For #1 - it looks right to me (It has been long time since I've done this). For function keys and arrow keys, etc, ReadKey first returns a 0, then the next call returns a code to indicate the key: 72 for up arrow, 75 for left arrow, 77 for right arrow, and 80 for down arrow. (The 27 is for esc.) So it looks basically right to me, based on my memory. Trace through the program to see what is happening. Bubba73 ^{You talkin' to me?} 23:03, 13 May 2013 (UTC)[reply]

PS - I would keep track of a line number, have a routine to translate the line number into the coordinates, and have the arrow keys change the line number and then update the screen coordinates. Bubba73 ^{You talkin' to me?} 23:07, 13 May 2013 (UTC)[reply]

And you don't need the begin/end inside the repeat/until. Bubba73 ^{You talkin' to me?} 01:40, 14 May 2013 (UTC)[reply]

I have a couple of other thoughts. (1) is ch an 8-bit character or could it be a 16-bit unicode character? If it is 16-bit, that could be the problem. (2) I'd test reading the arrow:

ch := readkey;
if ch = chr( 0) then
begin
  ch := readkey;

  case ord( ch) of 
    75 : writeln( 'left arrow');
    77 : writeln( 'right arrow');
    else writeln( 'other'); 
  end;
end;

Bubba73 ^{You talkin' to me?} 04:06, 14 May 2013 (UTC)[reply]

May 14

Convertion of MNEMONICS

HOW TO CONVERT MNEMONICS INTO MACHINE CODE ?117.204.231.251 (talk) 07:49, 14 May 2013 (UTC)[reply]

Wikipedia:Reference desk/Computing