Wikipedia:Reference desk/Archives/Computing/2012 March 28

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March 28

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ps3 superwihte option

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I have my ps3 hooked up to my 23 hp monitor over hdmi-dvi and been wondering as to what this option is better set to (that is Y Pb / Cb Pr / Cr Super-White (HDMI)) I got that RGB should be set to full if it's to be connected to a pc monitor, deep color hdmi- also should be auto, but this(Super-White ), is it better off being left off or on???

thanks — Preceding unsigned comment added by 77.35.25.237 (talk) 06:19, 28 March 2012 (UTC)[reply]

The only thing I can recomend is trying it and seeing what you like the best. Mrlittleirish 08:05, 28 March 2012 (UTC)[reply]

i just wanna know whether deep color output and that superwhite shit affect games if theyre only there for bluerayss and other media video than i could care less what they do

If I understand it correctly, it shouldn't affect games either way. If I'm wrong, and superwhite does require extra graphics processing, and you see a lag while playing games with it on, then turn it back off. StuRat (talk) 18:04, 28 March 2012 (UTC)[reply]

TMP???.EXE issue

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Since I did a full OS reinstall, my temp directory is crawling with EXE files, named tmp100.exe, tmp163.exe, and so on. Only some 3-digit numbers appear, but it goes on and on. Is that a virus?

The TMP EXEs degrade performance and occupy more RAM than the OS itself (XP). They keep popping up after deletion if at all possible; they are quite malicious in that they seem to trick Explorer most of the time into displaying nonsensical message boxes. For example, that TMP100 (rather than TMP100.EXE!) "cannot be deleted... check if the drive is neither full" (it's only half full btw, nothing more) "nor read-only" (it's an ordinary HDD, even Bill Gates knows that they aren't read-only media) "and if it is in use by another process" (so even the OS can't say which one is the process which keeps hugging the file -- WTF???) I can reboot and delete the files then, but what I really want is to kill the process which keeps downloading EXEs without my say-so, even if it's not a virus. 217.251.154.175 (talk) 11:24, 28 March 2012 (UTC)[reply]

Did you reinstall from official Microsoft media, or from something you got off the internet? 87.114.248.222 (talk) 12:00, 28 March 2012 (UTC)[reply]
That error message is uninformative, but common, and consistent with the files being legitimate. When you say that they're taking up RAM, do you mean that they're actually running, according to Task Manager? Anyway, don't randomly delete files in system directories; you should run a reputable anti-malware program instead. I believe that some people here have good suggestions. Paul (Stansifer) 18:58, 28 March 2012 (UTC)[reply]
This says it is malware. Run a good anti-malware program. Bubba73 You talkin' to me? 00:27, 29 March 2012 (UTC)[reply]
Uh... that site is an obvious scam. If you download the proffered "Fix-tmp100.exe" and run it, then you'll probably have malware. -- BenRG (talk) 02:41, 29 March 2012 (UTC)[reply]
[1] finds a very old malware with such a file name. However I agree with 87 here, you need to work out how you got this rather then just trying to kill a few of the symptoms, particularly if you don't know enough to work out how to delete the files or find the process spawing the files yourself. If for example you install Windows XP from some random media you got off the internet and didn't in any way try to verify the authenticity of what you downloaded, then it's easily possible the installation was screwed from the beginning and it's unlikely to be a good idea to try to save it. Nil Einne (talk) 04:10, 29 March 2012 (UTC)[reply]

87.114.248.222: XP from genuine Microsoft CD, and most programs (VLC, Winamp, Firefox and OpenOffice) from magazine DVD.

Paul: They are not in the system directory, but in the temp directory. Timestamps indicate they are downloaded while I'm dialed-up. Some appear in the process list, and I can kill the processes with no noticeable effect (except RAM and CPU usage, which is quite noticeable).

Oh, and if the OS cannot even pinpoint if it's running out of HDD space, experiencing a write error, or the file is already open (which would be detected before there is an actual access on the media), I doubt that the EXE files are anywhere good at all. They don't give the correct file name either.

Bubba73: What to say about that, besides Wikipedia:WHACK! ;)

Nil Einne: the media were genuine. The only EXEs I downloaded were Povray, Fractint, and some drivers. I'll have a look at the link you provided.

217.251.166.4 (talk) 05:25, 29 March 2012 (UTC)[reply]

For the record, I have the following files from yesterday: tmp166.exe tmp168.exe tmp163.exe tmp167.exe tmp161.exe tmp165.exe, in that order. I could delete all of them without any issues, probably because they are from yesterday's Windows session. None were running today. 217.251.160.76 (talk) 05:31, 29 March 2012 (UTC)[reply]

"When I was dialed up". You're on dialup then I take it? Is your XP fully up to date? Do you have a decent firewall? An out of date copy of XP will be compromised within minutes of going onto the internet, without you having to do anything, and the updates you will have to download are probably quite huge for a dialup user. If I were you I'd try and get a copy of Windows XP with SP3 preinstalled from somewhere reliable. 192.84.79.2 (talk) 10:33, 29 March 2012 (UTC)[reply]

You should run an anti-malware program. The error message is perfectly normal, but the fact that executables with those names are running is a bad sign. There's no point in attempting to fix the problem manually unless you're an expert. Paul (Stansifer) 20:23, 29 March 2012 (UTC)[reply]

Isn't there anything in-between? Like something to keep programs creating EXE files unless the user tells them to do so (which will amount to blocking all non-setup programs -- I don't code on my machine, or even ALL programs once the installation is complete). I'll try to get SP3 rather than SP2, but from what I've noticed, Bill Gates doesn't seem to close security holes anyway, just replace them with newer holes which the hackers don't know. One week later, they find out, and the process repeats itself...
"The error message is perfectly normal"? I'd say we used to have better error messages in the DOS years. At least we were asked if we wanted to "Retry/Abort/Ignore", rather than to press a nonsensical "OK" button for something that's not at all OK. If that's "normal" behavior, I have to wonder if Micro$oft ever uses its own products... but i digress...
I'll reinstall from a SP3 CD and see if that helps. By then, the topic will probably have fallen off the top of the reference desk. Will I have to start another topic or add to this one?
217.251.152.159 (talk) 05:30, 30 March 2012 (UTC)[reply]
Having malware on your machine is a serious problem, often in non-visible ways. Don't treat just the obvious symptoms. Also, service packs primarily consist of security refinements, so it is prudent to keep up-to-date, even though it is annoying. Paul (Stansifer) 14:26, 30 March 2012 (UTC)[reply]
Reinstalled. The issue seems resolved for now, but I still have to reinstall the applications and some drivers. BTW, I used a "XP+SP3" CD (as the IP user called it, "Windows XP with SP3 preinstalled"), only that it was not "from somewhere reliable", but from Micro$oft. LOL.
BTW, how would XP be "compromised within minutes of going onto the internet"? IMO that's an overstatement.
It's not like it would broadcast that a fresh copy of XP just went on-line, how would malware find it then? Or did you mean it would be infected that fast on certain obscure warez sitez? If it were like that, I'd re-reinstall XP without any SPs, as they only seem to double the boot time, and occupy twice as much RAM and HDD space (SP3 vs. SP0). The only web sites I use are WP, Commons, Yahoo, povray.org, Flicker, and the official sites of other software (mainly drivers), and I don't accept ANY mail with attachments. 217.251.158.24 (talk)
I don't know whether that's true or not, but it's not too implausible, given that the attackers have access to botnets which can just try every single IP address. For example, yesterday there were about a hundred malicious attempts to SSH into the machine I'm writing on. Attacks on vulnerable Windows services might be even more common, seeing as there are probably more newly-installed XP machines than Unix machines with root remote login enabled and guessable passwords. Paul (Stansifer) 18:33, 2 April 2012 (UTC)[reply]

name of deciding input for a logic gate

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What is the name for the logic input which decides the o/p of a logic gate? for example, a logic zero effectively decides the o/p of an and gate irrespective of other inputs. 117.230.35.251 (talk) 15:56, 28 March 2012 (UTC)[reply]

Image processing- Applying a gradient of defocus through an image

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Hi,

I'm looking to apply a blurring of an image so that the top appears sharp and in focus and the bottom blurry with a nice linearity in-between.

I understand that blurring can be performed by applying a Gaussian blur kernel, however I'm not sure how to weight this like I mentioned.

Would anyone know how or know of any resources which discuss how this may be done? — Preceding unsigned comment added by Kingstonjr (talkcontribs) 17:27, 28 March 2012 (UTC)[reply]

Are you looking to write your own program to do this, write a macro for an existing app, or use an existing tool ? And is this a one-time thing, or do you need to do this regularly ? StuRat (talk) 17:58, 28 March 2012 (UTC)[reply]
Sounds very much like your requiring the techniques used in sudo-tilt -shift. [2]. The best free software for doing this is GIMP (GNU Image Manipulation Program) [3] Does Gaussian blur, and everything, other than make you a really good cup tea (or coffee).--Aspro (talk) 18:18, 28 March 2012 (UTC)[reply]
Hi, well at the moment I'm using a combination of Python and ImageJ, ideally I'd like to code my own program for this in python as part of an existing program, but I won't be turning out high volumes of images so this doesn't need to be done at high frequency. KingstonJr (talk) 18:28, 28 March 2012 (UTC)[reply]
OK, for a high volume I was going to suggest an editable graph where you can adjust the exact rate of blurring as a function of vertical distance (similar to how many systems allow you to adjust brightness, colors, etc.), but for a low volume I'd just hard-code the rate of blurring and rewrite it when you need to change it. StuRat (talk) 18:35, 28 March 2012 (UTC)[reply]
OK thanks, so how exactly do I do that, I have a depth map varying vertically from 0 to 255 do I apply a Gaussian convolution kernel on that and then multiply onto my sample image? KingstonJr (talk) 18:44, 28 March 2012 (UTC)[reply]
I'm not familiar with the "Gaussian convolution kernel", but I'd assume it has variables for both the amount of blur between adjacent pixels and/or the distance at which pixels are blurred together. So, each of those variables would then change linearly. Not sure how they handle edges and corners, though, as there you lack some of the neighboring pixels to blur with. Cropping the pic a bit on all sides might be needed there, with more blurring requiring more cropping. StuRat (talk) 18:50, 28 March 2012 (UTC)[reply]
More theory than you ever wanted! On non-stationary convolution and inverse convolution. Because the gaussian kernel is so trivial, you probably won't have stability issues, but as always, check the math to ensure whatever algorithmically-generated coefficients you create are sensible. Nimur (talk) 18:57, 28 March 2012 (UTC)[reply]
And, an efficient implementation in FORTRAN. Source code is available. If you don't care about efficiency, you can avoid the helix, and use a simple 2D FIR filter with a gaussian kernel with a 2-dimensional python array. In truth, it's debatable which will run faster, on modern hardware, due to memory locality and caches. Nimur (talk) 19:07, 28 March 2012 (UTC)[reply]
And, for the less-technical user, here's a cheat, from a GIMP user's forum post: duplicate your layer; use a strong blur; and alpha-blend it on top of the original un-blurred layer, using a gradient alpha mask. This is not identical to a position-weighted blur; but it's visually similar, and easier to make happen without writing a GIMP plugin. Nimur (talk) 19:48, 28 March 2012 (UTC)[reply]

Is there a phone app that detects being inside polite areas, and auto-silence the phone?

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How such an app would work: The app works with your phone's GPS to detect that you're inside a symphony hall, school building, church, or other structures where higher manners are expected. Once you are, it automatically switches your ringer to vibrate (or silent, depending on preferences set.)

Is there such an app in existence out there? (Preferably for Android phones?)

If not, what would it take to program said app? What new advances would it require to make this possible? --129.130.18.69 (talk) 21:09, 28 March 2012 (UTC)[reply]

Sort of. Apps exist, such as Tasker, Llama and Locale that allow you to manage aspects of your Android phone based on predefined locations. So, if you want your phone to turn the ringer off when you get to work, you set 'Work' as a location, and tell it to be silent when you are at the location 'Work'. With this function, you could set all the places you might be likely to visit and need to be quiet, and set the phone to be silent when you are there. But if you wanted to go to the next step, and pro-actively determine the type of location you are in, and manage the phone based on that, these apps won't help. However, Tasker is slightly more powerful than the other two listed, and allows a large amount of customisation. If you have some coding knowledge, it might be possible to design some system that polls the location, checks the coordinates to see if your location includes any 'quiet places', and then mutes the phone. You can get information on developing with Tasker at http://tasker.dinglisch.net/. I suspect, though, that this might be a rather ambitious project! - Cucumber Mike (talk) 21:41, 28 March 2012 (UTC)[reply]
(ec with Mike) As to the last part of your question - I made the same complaint back in 2006. Potentially, things are better now, because so many people carry smart phones for which apps like the one you describe could reasonably be written. A modern smartphone usually has Bluetooth and WiFi capability, so one could implement a scheme where a given Wifi SSID (or something comparable on Bluetooth) could be taken as a signal to mute. There's always the risk some prankster uses that to disable ringing in other, non-quiet locations, or some business like a mini-mall with daft ideas misuses it or mis-installs it (so you miss a call because some crank who owns a laundromat is bleeding the "go silent" SSID out over the shared parking lot). A better regulated system (say with a cryptographic exchange) where the senders were available only to institutions with some reasonable need for one (after all, if you don't trust the system, you'll uninstall the app) might be sensible. Say you rent out the "go silent" emitters, and the proceeds go to some worthy charity. -- Finlay McWalterTalk 21:47, 28 March 2012 (UTC)[reply]
And someone in that Slashdot discussion (ah, back when Slashdot was worthwhile) linked to this 2000 article about the Q-Zone technology, which is pretty much what you're after. I can't find any mention of (that) Q-Zone (at least under that name), suggesting it didn't fly. -- Finlay McWalterTalk 22:01, 28 March 2012 (UTC)[reply]
I had an idea. How about using Tasker in conjunction with Foursquare to give you nearby venues in specific categories. Then, if you are <100m from a venue whose category = 'school', 'church', etc, it will mute the phone. Here's a script to allow auto-checkin - you might be able to modify that to check for a venue's category. Documentation on Foursquare's api is here - I'm afraid you'll have to get someone else to help with the coding if needed - that's a bit out of my league! - Cucumber Mike (talk) 22:53, 28 March 2012 (UTC)[reply]
One issue I see is that this is likely to depend on time, location within the building (if you're even within the building) and person. For example, a priest or minister in their office or whatever may not want their phone to be on silent unless they're meeting someone or if there is a mass or similar in progress even if that is part of the church. And while a student or parent may want their phone to be silent most of the time, and a teacher may want it on silent while in a classroom, depending on the the etiquette they may not want it while in the teachers lounge or their office, let alone a principal. Even a student may want it on at some times. Nil Einne (talk) 23:52, 28 March 2012 (UTC)[reply]

GNU/Linux: ln -s dereference "."

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When I type

ln -s ./Interface ~/.wine/drive_c/Interface

I get a symlink that points to itself. How do I specify to ln that by "." I mean the current working directory (meaning that it should resolve "." before building the symlink, rather than leaving it to be resolved when the link is followed)? NeonMerlin 23:26, 28 March 2012 (UTC)[reply]

You can't do that with a "." because the symlink target is always interpreted relative to the directory that holds the link. The symlink as stored on disk won't remember where you were sitting when you created the link, so you have to include that path to "get back here from there" as part of the symlink target. The easiest way is to use the absolute path of your current directory, which you can get from the shell variable $PWD.
ln -s $PWD/Interface ~/.wine/drive_c/Interface
If you don't like that, you have to imagine that you're already in the ~/.wine/drive_c directory, and write the path you'd use to get back to where you are now. If you're currently in ~/foo you could do
ln -s ../../foo/Interface ~/.wine/drive_c/Interface
That can be easier to understand if you cd to the ~/.wine/drive_c directory and run
ln -s ../../foo/Interface Interface
which you can abbreviate as
ln -s ../../foo/Interface .
68.60.252.82 (talk) 01:15, 29 March 2012 (UTC)[reply]