Wikipedia:Reference desk/Archives/Computing/2010 January 6

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January 6

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What program can be used to combine multiple PNG images into an animated GIF?

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I am looking for a program that can combine multiple PNG images into an animated GIF. Is there any free software on Windows or Mac I can use?--219.74.153.124 (talk) 01:31, 6 January 2010 (UTC)[reply]

The GIMP --Andreas Rejbrand (talk) 01:32, 6 January 2010 (UTC)[reply]
Tutorial --Mr.98 (talk) 02:51, 6 January 2010 (UTC)[reply]
ImageMagick can do it from the command line. Instructions. --Mr.98 (talk) 02:53, 6 January 2010 (UTC)[reply]

Bill Gates's code

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When's the last time Bill Gates himself wrote code for a Microsoft product?20.137.18.50 (talk) 13:24, 6 January 2010 (UTC)[reply]

Our article suggests that he was actively writing code for Microsoft products until around 1989. Ale_Jrbtalk 13:55, 6 January 2010 (UTC)[reply]
Of note, that claim is not backed in any way by the reference. The reference doesn't mention that Bill Gates ever wrote a single bit of code. In my opinion, we've had about 30 years of revisionist history to turn Bill into a great programmer when it all started as Bill being a great businessman with a mediocre product that other programmers wrote. -- kainaw 15:24, 6 January 2010 (UTC)[reply]
In fact it does; consider reading the reference more carefully? Check out (use 'Find') "Question about Bill’s programming." on the reference, where he states that his code last went live 8 years from when the speech was made, which was in 1997. Either way, if you have an issue with a reference, you should take it up on the relevant talk page rather than posting about it on the reference desk. Cheers, Ale_Jrbtalk 18:49, 6 January 2010 (UTC)[reply]
On a somewhat tangential note, according to Herb Sutter (who is definitely a competent coder), Gates is "a sharp guy with a broad and deep background and incisive questions", and made a remark about him "gesturing and making comments about simulating lambdas using macros instead of baking them into [C++0x], and variable capture consequences" at a technical review.[1] decltype (talk) 09:48, 8 January 2010 (UTC)[reply]
I'm also not convinced that Paul Allen & Monte Davidoff did all the programming for Altair BASIC and Bill Gates was just "great businessman with a mediocre product that other programmers wrote". Particularly since Paul Allen seems to have been the one meeting MIT (i.e. it doesn't seem BG was doing all the businessman side there). Both I believe came from relatively rich families (which isn't surprising since they went to a private school with computers in the 60-70s), so I don't see any reason there either. And also "Later, they made a bet on who could write the shortest bootstrap program. Gates won". If Paul and Monte really did all the programming, then I'm not particular sure why Paul let him hang around, and how he won the contest (unless you think both were just great businessmen and crap programmers).
Also I seem to remember Gates hacked into his school computer and changes his grades, probably not a particular difficult task and maybe not one requiring programming, but it does suggest he had some technical skills.
To be blunt and without intending to offend Kainaw or imply this was his? intention, it seems to me it's more likely the reverse. Bill Gates was a decent programmer, perhaps not the best, and a great businessman. Probably as a better businessman then a programmer, overtime he concentrated on the business side (although it's my impression that included evaluating code and programmers, I've heard in a mostly positive way that Bill Gates was an extemely perhaps excessively harsh critic, in a Ubuntu forum too so it doesn't seem like they had reason to lie) because that was his forte and however dubious some of his and Microsoft's tactics/actions may have been, he was still a decent programmer in his time.
People who don't like him and/or Microsoft like to ignore that he did have decent products which in the early days he was partially responsible for coding and like to think he just got lucky because of stupid rivals and being in the right place in the right time and was great (albeit perhaps ethically dubious in some instances) businessman with great marketing. Both of these obviously have some truth, but to put them down to the sole reason for MS's and BG's success is IMHO stretching. (I like to say the same about Intel and Apple as well but and infact think it's often more true for both albeit in different ways then for Microsoft but acknowledge they did have good products too.)
In fact I would go as far as to say, without meaning to include anyone in particular that in his prime he was probably at least as good as if not a better programmer then many programmers here; if any meaningful comparison can be made (probably the best is comparing the level of his skill compared to the average of peers for both) given the difference in time frames of the programming work.
P.S. I see from File:Altair Basic Sign.jpg he wrote the runtime stuff. I don't know if you can get access to the entire code, perhaps it's visible in the museum but if you can you can evaluate some of his earliest work for yourself unless you believe in 1975 they decided to lie about what Bill Gates actually did so they could spread a myth about him being a good programmer.
If you want to be ethically dubious and perhaps risk legal trouble, I know some Microsoft source code has leaked. I don't know if any of this includes anything with Bill Gates's work but if it does you could try and evaluate it yourself. Obviously it may be difficult to work out who wrote what I presume there may be some comments, headers etc of stuff he mostly or completely wrote, presuming you don't believe they decided to lie in their internal code to spread the myth (I guess to employees) that BG was a decent programmer.
Nil Einne (talk) 11:40, 8 January 2010 (UTC)[reply]

Linux based operating system emulator

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Back in the early '80's in the days of the Atari ST-1024 a Company out of Jacksonville, Florida (or Jacksonville Beach) developed an emulator for the Atari to allow it to run MSDOS programs on top of its TOS operating system. Is there a similar emulator existing today that will allow Windows applications such as Excel and Word and other windows based programs to run on top of the Linux operating system? 71.100.3.13 (talk) 14:29, 6 January 2010 (UTC) [reply]

Yes, see Wine (software). Another approach is using full virtualization software such as VMware Workstation to boot a copy of Windows inside Linux. -- Coneslayer (talk) 14:42, 6 January 2010 (UTC)[reply]

Computer's Clock Reset

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A couple of days ago, I noticed my computer's clock was wrong (fast by 5 or 6 hours), then when I came to reset it, I found the date was Friday, 22nd December 2006. It was making it difficult to visit websites because I had to authenticate certificates for them. Does anyone know what has happened here? I've reset the clock and restarted the machine and done a virus check with AVG and nothing has been found. Any information at all would be appreciated. --KageTora - (影虎) (Talk?) 18:27, 6 January 2010 (UTC)[reply]

Maybe the little coin-sized battery in your computer is almost dead. 20.137.18.50 (talk) 18:33, 6 January 2010 (UTC)[reply]
Seriously? I've been using laptops for over 10 years, and I've never heard of that before. --KageTora - (影虎) (Talk?) 18:41, 6 January 2010 (UTC)[reply]
It's very possible that I'm completely wrong, but the factory yields of the CMOS battery makers probably aren't exactly 100%.20.137.18.50 (talk) 18:50, 6 January 2010 (UTC)[reply]
The voltage of the CMOS battery of my Dell dropped below acceptable levels already after two or three years, making the clock loose the track of time if I disconnected the PC from the power grid. So it appears not to be very uncommon. --Andreas Rejbrand (talk) 19:09, 6 January 2010 (UTC)[reply]
I concur, it's most likely the little battery on the motherboard. Comet Tuttle (talk) 20:30, 6 January 2010 (UTC)[reply]

Funnily enough, it did actually happen after unplugging the computer and leaving it unplugged for a number of hours. Maybe this is something to do with my warranty running out last month and not being renewed...... :) Cheers! --KageTora - (影虎) (Talk?) 21:13, 6 January 2010 (UTC)[reply]

Actually, we have an article on this: Nonvolatile BIOS memory. That little motherboard clock battery is totally unrelated to your laptop's normal battery. If you unplug a PC (and yank the laptop battery, if it's a laptop) and leave it unplugged for a year and then plug it in and boot up, the clock will be correct, and it's because of that little motherboard battery. So, whether you let the laptop unplugged or not is irrelevant. The battery just decided to wear out, of its own accord. Comet Tuttle (talk) 00:48, 7 January 2010 (UTC)[reply]
so, is this user-serviceable? Can I just replace it myself or do I have to go through all the rigmarole of sending it off to be replaced (paying lots of cash because my guarantee ran out last month)? Can't I just go into a shop and get a battery then put it in myself? It's a HP G60, if that's any help. --KageTora - (影虎) (Talk?) 12:37, 7 January 2010 (UTC)[reply]

You can get a CR2032 at most grocery stores.20.137.18.50 (talk) 12:45, 7 January 2010 (UTC)[reply]

Thanks. So that is the one I need for a HP G60? Cheers! --KageTora - (影虎) (Talk?) 13:45, 7 January 2010 (UTC)[reply]

For a laptop, it will probably requre some disassembly to get to the battery. You probably want to verify the type of battery first and how to replace it. Check HP's support site and forums. Astronaut (talk) 14:40, 7 January 2010 (UTC)[reply]
Agreed; on a desktop computer it's really easy for a user to swap out his battery; but I have never done it on a laptop and remember being unable to disassemble my last laptop, for fear of breaking the plastic case; so you should contact HP and find out. Comet Tuttle (talk) 19:23, 8 January 2010 (UTC)[reply]
On my HP Pavilion dv6000 it is easy to replace the CMOS battery. --Andreas Rejbrand (talk) 22:57, 8 January 2010 (UTC)[reply]

Uncompromised computer

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If I had the resources to create and build an uncompromised computer to replicate the higher functions of the human brain what would those uncompromises be? 71.100.3.13 (talk) 20:59, 6 January 2010 (UTC) [reply]

Since we don't know how the brain actually works, how can we possibly hope to build a machine to replicate it? It's not a question of compromise, having better resources will not help until we have much better understanding. Theresa Knott | token threats 21:07, 6 January 2010 (UTC)[reply]
True, though there are at least a few things that would help it operate in a manner more closely resembling the human brain. Most of these are done in "hardware" in the human brain, but a computer could simulate most of them with software.
  1. Dynamic rewiring: The brain forms new connections and prunes old ones as part of the learning process. Any attempt to fully simulate a human brain would need to do the same
  2. "Voting" for signal transmission: In cases where more than one neuron connect to another neuron, the signal is transmitted based on a kind of vote; if only one neuron is "on" and several are "off", then the signal is often dropped (this is a drastic oversimplification)
  3. Massively multi-threaded: While the thread of consciousness is a single thread (or close to it), a lot of stuff is going on in the background. For example, when you overhear your name in a crowded room, multiple unconscious processes are involved in buffering the input, parsing it into words, identifying the key word, etc. And that's ignoring the fact that you could be engaged in dancing, having a conversation, etc., all of which involved numerous unconscious processes beyond the mere conscious decision to engage in the activity.
Now, it's entirely possible to limit your definition: Humans develop mental shortcuts as they learn something new, which is part of why the rewiring is necessary. A computer might recompute the result from scratch every time, so rewiring is unnecessary. In any event, Theresa is right; we don't know enough about the details of human brain function to replicate it exactly. It's not purely a technological problem; no matter how much hardware you throw at it, you still need more advanced neuroscience to figure out what exactly you are trying to emulate. —ShadowRanger (talk|stalk) 21:35, 6 January 2010 (UTC)[reply]

webcam as security

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i've had a quick search on the internet and i'm none-the-wiser, i'm pretty confused by IT at the best of times. so if anybody can help me pls do! my car has been vandalised a few times over the past 2 months so i thought a webcam would help me get some evidence. however i've only seen high end webcams advertising that they have software 'designed' for home security. can i buy a low end webcam such as this [2] and use some freeware software to save say 1 image every second to my HD? ty in advance 87.113.113.221 (talk) 21:16, 6 January 2010 (UTC)[reply]

There is a lot of webcam software available for any cam you can plug into your computer. You will want one that archives old photos (instead of just replacing the current photo). The quality of the webcam will decide how useful it is. For example, a low quality webcam that doesn't see anything when it is dark will be rather useless for catching people vandalizing a car outside at night. -- kainaw 22:01, 6 January 2010 (UTC)[reply]
Also you have to be aware of the zoom the fixed lens of an inexpensive web cam has. While outdoor web cams may have a lens that allows for a 150 deg viewing angle an indoor web cam may limit you to only 70 deg. On top of that you can not depend on a one frame per second rate to show the vandal actually vandalizing which defers the evidence you could have to circumstantial. Most security cameras rely on motion detection to assure that a single frame will show the vandal vandalizing. Another issue is whether your inexpensive camera has an infrared filter. If it does so you can remove it to see at night in dim light then you will have to sacrifice color. 71.100.3.13 (talk) 22:15, 6 January 2010 (UTC) [reply]
motion is one program, but linux only. --91.145.88.2 (talk) 22:08, 6 January 2010 (UTC)[reply]
The homecamera.com service, which is free at the moment, supports saving video clips and images to your account page on their website. (The fact that it's on their website seems useful in the home or office situation, so if an intruder walks in and steals the computer that has the webcam, he hasn't also stolen the video clips or images that the webcam just took of him.) I have not found what I want personally, which is a free piece of software that just saves 1 image per second, or whatever, to a remote computer. Comet Tuttle (talk) 22:30, 6 January 2010 (UTC)[reply]
Timelapse is very easy to do using a large variety of programs. Windows XP SP2 for instance included Movie Maker and while the worst possible software Mirosoft has ever included still can be used for time lapse. Movie maker also has the capability of pseudo motion detection processing of the pictures taken of which it will make an avi file. It, however, uses a lot of hard drive space but may work for an hour or so while you are out shopping. 71.100.3.13 (talk) 22:47, 6 January 2010 (UTC) [reply]
That's a fairly trivial script, at least on Linux - fswebcam to grab the image, ncftpput or scp to push to the web server, running under a cron schedule. -- Finlay McWalterTalk 23:14, 6 January 2010 (UTC

that's a lot of helpful info ty all. i have a security light which means i should be ok without IR, and i do have a partition set aside with linux installed so maybe it's time i worked out how to use it :-) really struggling for money atm so it seems a budget cam (other than it's field of view) should be okish i appreciate your advice

ty all

not sure why my 'ty all' is in a separate box but it was heartfelt :-) 87.113.113.221 (talk) 00:46, 7 January 2010 (UTC)[reply]

Because you started the line with a space :-) --Phil Holmes (talk) 10:54, 7 January 2010 (UTC)[reply]

I tried to ask Yahoo Answers, but

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it was too long and was way over the character limit. And besides, the people on sites like that are stupid. Wikipedians are much smarter and more helpful.

Here's my question:

What software (preferably free and quick) would be able to convert a .avi video file with a DIVX3 codec to a file that could be read by an Xbox 360? 96.255.178.76 (talk) 22:40, 6 January 2010 (UTC)[reply]

FFMPEG, which can run on your Windows or Linux PC, can convert video to and from many formats. An XBox360 should be able to play MP4 formats. Alternatively, you can follow the specific instructions in Xbox 360 conversion guide. Nimur (talk) 23:07, 6 January 2010 (UTC)[reply]
Another option may be IRFAN but I'm not sure about xbox conversion. 71.100.3.13 (talk) 03:09, 7 January 2010 (UTC) [reply]
Thanks. I considered Irfan but remember using it a while ago, didn't like it and wasn't sure what format to use. Nimur's advice seems great. Thanks! 96.255.178.76 (talk) 01:52, 8 January 2010 (UTC)[reply]

FORTRAN-90 Array Syntax

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I came across some unusual array syntax in some 11-year old Fortran 90 code. It's causing a segfault, presumably because the array index is accessing out-of-bounds. Unfortunately, the code is accessing the array elements in vector syntax that I am not familiar with.

  write_subroutine( cmplx(x(::N0,:), y(::N0,:)),  N1*N2*8 );

N0, N1, and N2 are constants. write_subroutine works properly if the input is valid. Clearly, something with the double-colon syntax is accessing invalid parts of vectors x and y. What is this double-colon vector syntax? I'm inclined to believe that it is accessing the vector in strides of N0 (that is, every N0'th element of the entire vector), but if that is the case, how am I getting a segfault? I can't find documentation for this weird vector syntax. Any Fortran90 vector gurus know what the :: syntax actually means? Nimur (talk) 23:14, 6 January 2010 (UTC)[reply]

windows vista problem, application wont launch, side-by-side configuration incorrect

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hey i need help guys please. when i try to launch the application i get this error: the application has failed to start because its side-by-side configuration is incorrect. Please see the application event log for more detail. so i check the event log and it says: Activation context generation failed for "(file)". Dependent Assembly Microsoft.VC90.MFC,processorArchitecture="x86",publicKeyToken="1fc8b3b9a1e18e3b",type="win32",version="9.0.21022.8" could not be found. Please use sxstrace.exe for detailed diagnosis. what is going on?? ive never had this happen before.--Longhorns666 (talk) 23:16, 6 January 2010 (UTC)[reply]

and i use sxstrace.exe, but the command prompt appears for 1 second and then disappears, so i cant even use it!--Longhorns666 (talk) 23:17, 6 January 2010 (UTC)[reply]

(1) What application? (2) Googling "sxstrace.exe" yields, among other things, this link, which is a forum in which the "side-by-side" error is mentioned — any help there? (3) When the command prompt appears in Windows and disappears immediately, the fix is to instead run cmd.exe and from the command prompt, run your app (in this case, just type sxstrace.exe). When the executable is done you'll remain at the command prompt so you can look at the output of your app. Comet Tuttle (talk) 00:44, 7 January 2010 (UTC)[reply]