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January 13

distinguish sound files

I know I already asked this, but I'm hoping there might be someone here today who has an answer.

I have sound files from field recordings that I recently found are not identical to their back-up copies despite having the same time stamp. (I discovered this when I scanned my comp for duplicate files.) I'm afraid that some program I used to listen to them may have made changes, though I never saved anything. This won't matter if it's metadata, but I wonder if some got slightly corrupted. I need to send copies to various archives, and am not sure which copy to rely on. Is there any free/shareware out there that will show me where the differences are? — kwami (talk) 22:59, 5 January 2011 (UTC)

As I mentioned before, if you can checksum the files, you can establish exactly-identical files. Similarly, checksumming the data portions of the files but excluding the metadata could establish exactly-identical audio data. For "almost identical" audio, the situation is much harder. This could be the case if the mp3 or file were transcoded - even if there is no perceptible change in audio quality.

Both Audacity and GNU Octave can plot, display, visualize, and manipulate audio files from standard formats. You can load audio files in Octave with auload:

% Example GNU Octave script to load and compare two WAV files:
[data1,fs1] = auload("file1.wav");
[data2,fs2] = auload("file2.wav");

% Check that the sampling rate and file sizes are identical
assert(fs1,fs2);
assert(size(data1), size(data2));

%Plot the residual error between the two audio signals
resid = data2-data1;
plot(resid);

If the audio is identical, the residual should be exactly zero; if the audio files are similar, the residual should be small. You can use ffmpeg to convert mp3 to wav files before diffing them. (I've thought about diffing the compressed data; but arguably, it is really best to decode it first, and then perform comparisons. It is best to diff an uncompressed waveform decoded by a standard tool - ffmpeg - because different decoders may produce different waveforms from the same mp3 data. Any tool that reverses the lossless coding of an mp3 must apply interpolations and to some extent, an heuristic algorithm. By using a standard tool like ffmpeg up front, we avoid hassles and get a uniform waveform). You can convert files from mp3 to wav easily using this command:

ffmpeg -i file.mp3 file.wav

If you are familiar with more sophisticated audio signal processing, you can design a program to check if the audio has been "trivially" altered, such as changing the volume, adding or removing a delay, and so on, using xcorr and other more complex audio processing. Unfortunately, because sampled audio is complicated, there is not an easier way to determine "almost" identical files. You could also investigate using a binary diff tool, but I have never found those to be very helpful. You could also wrap these conversions and comparisons into an Octave or other script. Nimur (talk) 23:30, 12 January 2011 (UTC)

As mentioned compression changes are more difficult to detect, but one potential (it a little work intensive) solution to other concerns would be to load both into a program like Goldwave (and I presume Audacity would have a similar capability), which will show the exact waveform. First check the attributes of the file for bit-rate, length, ect. then zoom in to a reasonable view that allows you to visually compare. It would be easy to do the things mentioned by Nimur (if the volume was increased, the peaks will be higher, a delay or echo will result in slightly shifted peaks or echo spikes. It might be a worthwhile way to quickly see if anything has been done 65.29.47.55 (talk) 22:13, 13 January 2011 (UTC)

Thank you, Nimur and anon! I'll try this out. I have .wav files which have not been intentionally altered since they were recorded (Marantz digital recorder); all I have done is transfer them from one drive to another, and play them with programs like SoundForge and PRAAT. — kwami (talk) 23:57, 13 January 2011 (UTC)

Big files and Fraps!

Hi, I use a program called "Fraps" to record and save videos of games that I play. I store the videos on my hard drive to later edit and upload to youtube. The only problem is that the video files end up way too large and they take up over 200 gigs on my hard drive. What are some programs that will help me scale down the size of the files without losing the high quality of the videos? What is the best program for this and whats the best free program for this?(I might be willing to pay some cash if the free programs prove to be too infective). I'd really appreciate some help and thank you for your time. :) (Ahalol123 (talk) 00:10, 13 January 2011 (UTC))

If you have money, Adobe Premiere will do this. Whether or not you have money, the free program VLC media player will do this, too. Of course, compression comes at a cost. You can tweak the video compression settings as you like to choose the tradeoffs between quality and file size — the higher the quality, the higher the file size will be. In your shoes, I would try several of the VLC settings using the highest quality compression settings possible and I think you'll be pleased. Comet Tuttle (talk) 00:17, 13 January 2011 (UTC)

Converting the video to XviD or h264 or something similar will drastically reduce the filesize. See Avidemux, Handbrake, MEncoder and Category:Free_video_conversion_software 82.44.55.25 (talk) 00:20, 13 January 2011 (UTC)

Thanks for all the help! I really appreciate it! My computer already has Adobe premiere installed, so money isn't really a problem. I'll try out both and see how good they work because I'm only really looking for the most efficient and quick program to use as I have a lot of files. Thanks again for the support! (Ahalol123 (talk) 00:30, 13 January 2011 (UTC))

Depending on what version of Premiere you are running, you may want to be sure to choose "Adobe Video Encoder" (or a similar item under the File menu) rather than "Save As" or "Export" — the former gives you the flexibility and codec options you'd expect. Comet Tuttle (talk) 22:44, 13 January 2011 (UTC)

FFMPEG, and the user-friendly version provided with the WinFF user-interface, are free software. FFMPEG supports conversion to and from almost all major formats. It is the core video engine used in almost all free and commercial (in modified form) video processors and players; so using FFMPEG nearly guarantees compatibility with most video players. Nimur (talk) 01:01, 13 January 2011 (UTC)

There's a lot of suggestions here, which one is the best? Thanks again for all the help. (Ahalol123 (talk) 02:15, 14 January 2011 (UTC))

I'm pretty sure every program listed above (excluding Adobe and maybe mencoder) uses FFMPEG "under the hood." So, you'll get the same results. HandBrake, WinFF, and so forth do have some value-add, being a bit easier to use (ffmpeg is a command-line tool); so it's a matter of your preference. In my opinion, the command-line interface is very easy to use; here are instructions for starters. Nimur (talk) 04:44, 14 January 2011 (UTC)

I tried using VLC media player and Virtualdub but I couldn't figure out how to do it properly, and then I used WinFF like you said but it took an extremly long time to compress and I was wondering if there's anyway to make it automatically compress another video after its done with one. (Ahalol123 (talk) 20:41, 15 January 2011 (UTC))

Being a command line, you can type several lines together into a script file (end in .bat) and then execute that. Video encoding takes plenty of CPU, so you will need to pick te options that make the best use of your cpu's instruction set. If you have multiple disk drives put your output on a different disk from the input. Graeme Bartlett (talk) 21:07, 15 January 2011 (UTC)

I only understood like 1/5 of what you just said, LOL. (Ahalol123 (talk) 21:55, 15 January 2011 (UTC))

Graeme was explaining that video processing normally takes a long time. It can take anywhere from several minutes to many hours to process "normal-sized" videos on moderately-powerful computers. If you want to squeeze a bit more performance, you can follow those suggestions, but it's probably not going to make a huge difference. Nimur (talk) 17:54, 16 January 2011 (UTC)

Flash 8 (ActionScript 2.0) question

Another question because of my complete n00bness! So, on the first frame:

stop();
var a:Number;
var c:Number;

On a button (I called it 'hello') in the same frame:

on(release){
	a = (c) * (3);
	gotoAndStop(2);
}

There is a textbox in the same frame with the variable c. You can input text in it (I don't know the exact name for this kind of boxes because I'm using the Chinese version.)

On frame 2, there's a textbox (which is able to display variables, but you can't input anything into it), and its variable is a.

What went wrong? Thanks Kayau Voting IS evil 10:48, 13 January 2011 (UTC)

What is not behaving the way you expect it to? I see your code, but I don't see what you are expecting it to do. --Mr.98 (talk) 14:45, 13 January 2011 (UTC)

Make sure the input text box has an instance name. (In the example below, I named it txtInput. Then, try something like this:

on(release)
{
	c = txtInput.text;
	a = (c) * (3);
	gotoAndStop(2);
 }

Then, add a text field to the second frame, make it dynamic (not static), and give it an instance name. In the example below, I called it txtOut:

stop();
txtOut.text = a;

--Best Dog Ever (talk) 19:22, 13 January 2011 (UTC)

Thanks! (BTW, it's for the same game that I asked about last year. Yeah, I still haven't finished it.) Kayau Voting IS evil 13:40, 14 January 2011 (UTC)

Copy (file differences)

If I have a 10GB file and change one tiny part of it, to copy the modified file to a backup drive with Windows 7 requires that the entire 10GB be copied. Is there a way to copy just the new changes of the file, similar to how DropBox only uploads the changed parts and not the entire file? 82.44.55.25 (talk) 14:56, 13 January 2011 (UTC)

If the file is in a human-readable text format, then the diff program can extract the differences, and the patch program to reapply them to the original. These are standard UNIX tools, and should be available on MacOS. There are ports to MS-Windows, including the cygwin and mingw toolsets. BTW, I've taken the liberty of clarifying the question's title CS Miller (talk) 15:27, 13 January 2011 (UTC)

This is delta encoding; the standard tool I know for it is rsync (the article lists Windows implementations). --Tardis (talk) 15:30, 13 January 2011 (UTC)

The problem is that file systems keep track of when each file was last modified, but not of which parts were modified when. Therefore, you would have to read the old file in its entirety to figure out which parts had changed, and that will take about as long as blindly writing over the whole thing. Rsync saves time when the bottleneck is a slow network connection, rather than the disk. It still reads the whole file, but it uses CRCs to compare the old and new data without sending it over the network. -- BenRG (talk) 23:23, 13 January 2011 (UTC)

Developing Native iPhone applications on Windows

I know that there are ways of writing iPhone applications on Windows and I was wondering how I could set up a native build environment on Windows that can compile to current (iOS 3.x and iOS 4.x) versions of iOS. iOS devices use an ARM architecture and GCC and LLVM/Clang can compile to ARM instructions sets so how would I go about using one of these to compile an iOS app into an IPA file (a ZIP file that contains the app payload for iTunes? Please, save any comments about how iOS SDK is only for the Mac or how the Apple won't allow apps developed with third-party tools because I couldn't care less about Apple's rules. --Melab±1 ☎ 16:39, 13 January 2011 (UTC)

Because Apple iPhone's system architecture is proprietary, and nobody has yet reverse-engineered it, writing software for their phone without their SDK will be much more complicated than merely compiling for the CPU. (GCC can trivially cross-compile for many architectures). Compiling valid machine-code for their CPU is step one. But you also need to know what addresses and interface protocols they use for at least the following: their boot sequence; their nonvolatile storage; their video output interface; and their user-input interface. As I understand the iPhone and iPod products, they also have hardware signed executables - so you will have to learn that system and either bypass or spoof it. To accomplish these tasks, you could assume whatever you like about those systems, and perform a trial-and-error compile cycle, but if you are incorrect, you may compile a perfectly functional and valid executable that is not able to do anything on the iPhone. You probably also will want to reverse engineer their network stack, their peripheral devices, and presumably any hardware accelerators that reside on- and off-chip on the phone. Apple doesn't publish what memory-mapping, CPU instruction extensions, or other unknown mechanisms are used to perform those interfaces, so you will have to "guess", based on any information you can glean from their official development environment. Nimur (talk) 17:32, 13 January 2011 (UTC)

200 Apple

This link returns the http status code "HTTP/1.1 200 Apple". List of HTTP status codes does not list this, nor can I find any information via google on what "200 Apple" is about 82.44.55.25 (talk) 19:44, 13 January 2011 (UTC)

In HTTP, like several other Internet protocols, the text after the 3-digit code doesn't have any strict meaning. It's just there to make the response more human-readable. A server can use the generic "OK" or something more informative. This "Apple" probably just means that some Apple software is being used on the server. Whatever it is, it's meaningless to the HTTP client. See RFC 2616 section 6.1.1 67.162.90.113 (talk) 20:23, 13 January 2011 (UTC)

It's informational as .113 says. Apparently it's put out by systems running WebObjects, which is weird because there's also a "X-Powered-By: ASP.NET" header there. --Sean 20:54, 13 January 2011 (UTC)

remove duplicate lines

I have a text file with lets say a million lines in it, but many are duplicates. How, on Windows 7, could I automatically remove the duplicate lines leaving only one instance of each? 82.44.55.25 (talk) 20:07, 13 January 2011 (UTC)

http://www.netikka.net/tsneti/info/tscmd097.htm ¦ Reisio (talk) 20:24, 13 January 2011 (UTC)

1. Install ActivePerl. 2. Run this:

perl -ne 'print unless $saw{$_}++' input.txt > output.txt

Done. --Sean 20:59, 13 January 2011 (UTC)

Twitter Terms of Service

In their official Terms of Service, Twitter states: "We may not monitor or control the Content posted via the Services and, we cannot take responsibility for such Content." I am confused about the phrase "we may not..." Does this mean they are not permitted to monitor or control the content, due to some legal obligation? (Wiretap legislation comes to mind). Or, does this merely mean that they might not choose to monitor or control content, depending on their mood? Nimur (talk) 21:09, 13 January 2011 (UTC)

I think they mean the latter; it's their get-out clause when their service is misused in some way, or when a kid posts a suicide note or something. -- Finlay McWalter ☻ Talk 21:17, 13 January 2011 (UTC)

Yes, I would read it as the latter. Think about it: how likely is it that a company would ban themselves from "monitoring" the content on their own service? "Monitoring" might mean as little as "a guy looks at a post once in a while". Comet Tuttle (talk) 22:42, 13 January 2011 (UTC)

I understand (although I may be wrong) that it operates in a similar way to facebook in that regard - They don't employ people to monitor all facebook posts/updates, but they do have a team to respond to notifications about spam posts/users or innapropriate content. This system relies on users of the service (in this case twitter) reporting the content/post/update - Facebook has a 'flag' button to report such content, twitter allows you report spam-users. You may have already read this, but if you haven't, it gives a little insight into how they deal with problem users Darigan (talk) 15:11, 14 January 2011 (UTC)

(Above unsigned post not added by me.) In concurrence with CT and FM, I'd say basically it's way of covering both their bases. It's a disclaimer they don't normally monitor, so aren't responsible for content. But they also don't want to suggest they never monitor, since they may very well do so in some cases and don't want people taking their statement as a guarantee they don't monitor (and trying to sue them if they do). As unsigned says, as with many services they almost definitely primarily rely on users reporting problems. Nil Einne (talk) 14:41, 14 January 2011 (UTC)

The post above Nil Einne's was mine, forgot to sign it, sorry all (just added sig now) Darigan (talk) 15:11, 14 January 2011 (UTC)

Screen saver with own pictures

I want to make someone (who uses Windows XP) a screen saver with own pictures. I know that Windows XP allows you to use any pictures with a Windows screen saver... but I'd rather use something else as long as it's a) free, b) add-free, c) easy-to-use / -install (and ultimately de-install!), d) doesn't bog down the system, and e) small. Does software like that exist?

(The background is that I got from that person a screen saver as a present years ago when Windows didn't yet offer the built-in saver. Now I'd like to "return" the present, a little tongue-in-cheek of course, but I'd rather not just copy pictures onto the person's computer saying "Hey, use those with your own software!" On the other hand we both know of course that Windows offers the service for free and with decent quality, so it shouldn't be any worse than that.) Thanks a lot, Thanks for answering (talk) 22:49, 13 January 2011 (UTC)

Running out of memory when using IE on YouTube

If I run through several videos in a YouTube Playlist while using IE, eventually my computer stops running videos because IE (I'm using IE 8) fills up all of the available memory. I can look at Task Manager and see that iexplore.exe is huge, and I have to kill IE and restart to continue watching videos. This does not seem to be happening with Firefox, though I don't normally use Firefox to watch YouTube videos. Is there something I can do to get IE to release its used memory, or is this just a problem that I'll have to deal with by using Firefox on YouTube all the time? (I already use Firefox for Wikipedia because IE takes eons to display history pages in WP). Corvus cornix_talk 23:53, 13 January 2011 (UTC)

You might consider using Google Chrome Frame, which works inside IE. You could likely then get even further performance boosts by joining the YouTube trial which uses natively supported WebM video playback instead of Flash-embedded playback. …or you could just stop using IE. :p ¦ Reisio (talk) 01:38, 14 January 2011 (UTC)

Either close down browser tabs you don't need (each of the tabs is a separate Internet Explorer process, using up a lot of memory), use a more memory-efficient browser, or install more memory. 118.96.158.185 (talk) 01:38, 14 January 2011 (UTC)

The reason why I prefer IE over Firefox is that my RealPlayer is configured to download videos when using IE, but not when using Firefox. Corvus cornix_talk 02:20, 14 January 2011 (UTC)

Wha? ¦ Reisio (talk) 02:32, 14 January 2011 (UTC)

??? Corvus cornix_talk 03:03, 14 January 2011 (UTC)

I'm betting that Reisio is wondering why anyone would use RealPlayer. Go ahead and read the article to see what I mean. Dismas|^(talk) 03:20, 14 January 2011 (UTC)

Because it lets me download videos direct from the video screen. Of course, they're in .flv format, but then I can convert them for my video MP3 player. Corvus cornix_talk 03:24, 14 January 2011 (UTC)

Did you know that you can cut out a step by doing all of that in Firefox? Dismas|^(talk) 03:54, 14 January 2011 (UTC)

Thanks, that was good to know, but RealPlayer lets me download videos from other sites as well. Corvus cornix_talk 04:18, 14 January 2011 (UTC)

How about this add-on instead? Or you can try upgrading RealPlayer and/or Firefox. I have both RealPlayer SP 12 and Firefox 3.6 installed, and that version of RealPlayer claims to support "Web Download & Recording" on Firefox (it has the options to enable the feature, but I never actually used that feature). 118.96.158.185 (talk) 04:51, 14 January 2011 (UTC)

Hah. Thanks. I didn't know about that. I didn't have to do any configuring to get it to work with IE. Cheers. Corvus cornix_talk 05:21, 14 January 2011 (UTC)

January 14

Google docs arrow keys

Hi. I use google docs and by and large it's great. But sometimes the arrow keys on my keyboard don't work. This happens on linux and mac, always using the latest version of firefox. Does anyone else experience this? It's very annoying because I have to use the mouse to navigate and this takes my fingers away from the keyboard. Does anyone have any advice? Robinh (talk) 10:13, 14 January 2011 (UTC)

Since nobody's answered, a wild guess: Are you using a laptop with a touchpad as well as a mouse, and is it just the arrow keys that cease to work when this happens, or does the keyboard stop working? If so, what's happening might be that you're accidentally touching the touchpad when the mouse pointer is outside your document. That will cause your document to lose keyboard focus, and you'll need to use the mouse to give keyboard focus back to your document. If this is the case, a solution would be to deactivate the touchpad, or to reduce its sensitivity. --NorwegianBlue ^talk 10:05, 15 January 2011 (UTC)

Hi. Nope, the keyboard works fine but the arrow keys do not apparently do anything. It's very annoying (but only a problem about half the time I use googledocs). Cheers, Robinh (talk) 09:10, 16 January 2011 (UTC)

USB media - hard disk or not?

On a recent Linux distribution, which commandline tools can tell me whether a USB device is an external hard disk or another (storage) device like a flash memory stick? I'm writing a script that is supposed to write data to an external hard disk (connected via USB), but I want to avoid accidentally overwriting a flash memory stick that the user might have left plugged in. -- 78.43.71.225 (talk) 11:02, 14 January 2011 (UTC)

You might be able to examine /sys/class/block/<devicename>/device/model to detect a flash disk. (where <devicename> is something like sda, sdb, etc.). -- JSBillings 16:28, 14 January 2011 (UTC)

I found no /sys/class/block/<devicename>/device/model, only a /sys/block/<devicename>/device/model, which contains part of the manufacturer name for each device, it seems. I did find /sys/block/<devicename>/removable, which contains "1" for a flash memory stick, and "0" for both the first hard disk as well as the one connected via USB. I'm not sure that this is a reliable way of detecting a hard disk, though. Any further suggestions? -- 188.105.132.219 (talk) 16:56, 14 January 2011 (UTC)

IIRC, MS-Windows 7 uses the device's sustained read speed to detect if it is flash drive, you might need to do something similar. CS Miller (talk) 17:17, 14 January 2011 (UTC)

Use smartctl? I don't think flash drives and memory sticks have S.M.A.R.T. information, while I think hard drives and SSDs do. 118.96.156.2 (talk) 17:25, 14 January 2011 (UTC)

Hard drives and SSDs do have S.M.A.R.T. information, but it seems not every USB controller is able to forward this info to the host, so this isn't reliable, either. :-( -- 78.43.71.225 (talk) 17:38, 14 January 2011 (UTC)

smartctl, like hdparm -I works on ATA/ATAPI devices (that is, devices on the ATA and workalike busses). In my limited experience (that is, checking a couple of Ubuntu systems today, trying to find a decent answer to this question) suggests that the Linux usb mass storage device driver stack doesn't implement the requisite ioctls (even for an ATA drive in a USB enclosure), so neither seems like a viable option. -- Finlay McWalter ☻ Talk 17:39, 14 January 2011 (UTC)

Do you have "usb-devices" installed? When I run that, I see info under "Product=" that identifies what is plugged in. I can identify USB storage devices because they have "Driver=usb-storage". I tested a thumbdrive and it came up "Product=LEXR PLUG DRIVE". It is possible that "Cls=08" may be a thumbdrive storage class, but I don't have a usb harddrive to compare with. -- kainaw™ 17:39, 14 January 2011 (UTC)

usb-devices is not a supported command on my install of Ubuntu Hardy Heron. :-( According to packages.ubuntu.com, it is also not part of any package belonging to Hardy. :-( -- 78.43.71.225 (talk) 17:53, 14 January 2011 (UTC)

I don't think that's sufficient. Below is a trace of usb-devices on a machine with a SanDisk Cruiser USB flash disk and a LaCie USB disk enclosure:

T:  Bus=01 Lev=01 Prnt=01 Port=04 Cnt=02 Dev#= 40 Spd=480 MxCh= 0
D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
P:  Vendor=059f ProdID=1019 Rev=00.01
S:  Manufacturer=LaCie
S:  Product=LaCie Desktop Hard Drive
S:  SerialNumber=00E0010080086
C:  #Ifs= 1 Cfg#= 1 Atr=c0 MxPwr=2mA
I:  If#= 0 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage

T:  Bus=01 Lev=01 Prnt=01 Port=06 Cnt=03 Dev#= 39 Spd=480 MxCh= 0
D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
P:  Vendor=0781 ProdID=5151 Rev=02.00
S:  Manufacturer=SanDisk
S:  Product=Cruzer Micro
S:  SerialNumber=2400121D52C0F953
C:  #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=200mA
I:  If#= 0 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage

I don't know what the Atr=80 field is, but other than that only the MxPwr=200mA field looks discriminatory. -- Finlay McWalter ☻ Talk 17:52, 14 January 2011 (UTC)

Here's a hack: lsusb -v, and for each device find its MaxPower setting. For me, a genuine flash external disk has a MaxPower of 2mA, whereas a "real" disk in a USB enclosure has a MaxPower of 200mA. Other than that, I don't know of a way to determine the actual media of a linux block device (bar a vendor/deviceID lookup using the data JSBillings' post retrieves, which is a labourious business). -- Finlay McWalter ☻ Talk 17:46, 14 January 2011 (UTC)

Sadly, I'm getting just the opposite result here: the stick draws 200mA, the hard disk only 2mA (it has an external power supply) -- 78.43.71.225 (talk) 17:56, 14 January 2011 (UTC)

Sorry, I mixed the two up - if you look at my trace above, I get the same as you. The SanDisk is the flash stick. -- Finlay McWalter ☻ Talk 17:59, 14 January 2011 (UTC)

Okay, now I will have to look for a USB-powered hard disk to check how that one shows up. -- 78.43.71.225 (talk) 18:08, 14 January 2011 (UTC)

The fly in the ointment will be bus-powered usb disk enclosures (the slim kind that take laptop hard disks). -- Finlay McWalter ☻ Talk 18:13, 14 January 2011 (UTC)

Drat, so we're back...

... to square one, I guess. -- 78.43.71.225 (talk) 18:22, 14 January 2011 (UTC)

On a more fundamental level, what is the difference between a hard disk and a flash stick? Capacity? Moving parts? Nowadays there are solid state hard drives - no moving parts, used like hard disks. mp3 players can be plugged into USB and look like memory devices - some have rotating disks, some don't. A device might accidentally give a hint about its internal mechanics, or it might not. Should you really care?

If you really need to make a guess, how about looking at the device's maximum storage capacity, or available free storage, and deciding that anything over X GB is a "disk".

Or how about this: on disks that are allowed backup(whatever) devices, manually create a file called "this-is-a-backup-disk-please-write-backups-here". Your script will check for that file and if it is there, the script will do its thing. Random memory sticks won't have the file and your script will abort. 88.112.59.31 (talk) 20:34, 14 January 2011 (UTC)

Sadly, these approaches don't work, or at least not for long. I'm trying to build a box where the user can pull copies of a hard disk image onto "the real thing". Some of these disks are SSDs for embedded systems and have capacities of 60 or 64 Gigabytes - and with USB flash memory becoming larger and larger, using the maximum capacity of the medium as an indicator won't work (at least not for long).

The reasons why I need to be able to tell a flash memory stick apart from a SSD or moving-parts hard drive are:

• Sometimes, data (new images) is transferred to this box via flash memory stick. Overwriting this stick, just because a user forgot to remove it in time, would be anything but user-friendly.
• The SSDs or hard disks will be plugged in via SATA interface in their destination systems (in other words, the USB enclosures the users bring along are only temporary casings) - a flash memory stick doesn't have a SATA interface, plus the machines that still use moving-parts hard disks write to the disk pretty often, so flash memory will wear out. (I've seen two new high-quality USB sticks die in a similar application in the last 6 months. I know that these days, this shouldn't happen any more, but I guess these claims only refer to home use - heavy-duty writes like logging or database access, even today, still do kill flash memory sticks, I have seen it happen.)

Since this box will be available to a larger group of users, I have no control over the USB sticks or hard drive enclosures they will bring along, so writing a "it is (not) safe to overwrite this disk" file on the media won't work.

-- 188.105.132.219 (talk) 21:52, 14 January 2011 (UTC)

Why not present a user interface from your script to let the user pick the correct mode of operation? 118.96.154.64 (talk) 23:23, 14 January 2011 (UTC)

(EC with above) An obvious question that comes to mind that I think others may have been thinking of: Are you sure no one is ever going to connect what you consider a HD, that they don't want to be overwritten, to the computer? If you aren't even if you can differentiate the 2, it's not going to ensure you don't overwrite stuff people don't want you overwriting.

Is it possible you're approaching this from the wrong way? I kind of skimmed thru the discussion so forgive me if I missed it but is there some reason you can't ensure the HDs you want to use are identified as such. Whether a file, volume name or simply requiring the disks are cleared before they are brought to be written i.e. just don't overwrite anything.

If this doesn't work, is it possible to just ask the user? Use double prompts perhaps, with clear phrasing, perhaps even requiring they type YES or something (whatever you think is necessary).

The other alternative is probably physical. Is it possible to designate one set of USB ports or one port for bringing data? And one set or one port for connecting the backup devices. Make sure these are properly seperated and perhaps put the ports for backup devices behind a hinged door or something with a clear label indicating anything connected to them may be overwritten. Then design your script so it only writes to disks connected to these ports.

In both cases some people may still be clueless or careless so wind up overwriting what they don't want overwritten but ultimately there's only so much you can do to stop people doing stupid things.

Nil Einne (talk) 23:31, 14 January 2011 (UTC)

The "Store image" function should probably be restricted or removed anyway (either password-protected or disabled – images should be stored using special root access). The case is, what if someone were to present an incorrect, corrupt, malware-infected, etc. image to the system? Will that image be restored into subsequent disks presented to the system for restoration? 118.96.154.64 (talk) 23:50, 14 January 2011 (UTC)

All the users of this system belong to Field CircusService, and the machines they're imaging a) don't run Windows and b) are not accessible to end-users, plus the image they're storing is an individual image for each machine, so even if something does go belly-up, it cannot spread to other machines. This makes me believe that the risk in my particular case is rather low. They know that if they mess with the system, they end up creating more work for themselves (reimaging is faster than reinstalling and reloading the config, but they do have access to the full installation procedure as well, so we're not creating a deadlock situation here). I just want to keep them from accidentally shooting themselves in the foot by overwriting a forgotten USB stick. -- 78.43.71.225 (talk) 13:55, 15 January 2011 (UTC)

Thank you for all of your input. Since it seems nigh impossible to detect the media type via USB, I will probably be using a SATA drive bay for the disks. Of course, this means the users will have to power-cycle the computer before swapping hard drives, as the standard SATA controller doesn't support hot-swapping, but since the only media connected via USB will be a memory stick, all I have to do is check for connected USB devices and complain/abort if there is one. Since all USB devices automatically get mounted under /media/usbn, something like

umount /media/usb*
lsmod | grep usb_storage && rmmod usb-storage

and checking its return code (if the module could not be unloaded, it means that a usb storage device is still in use) should do.

After that,

fdisk -l|grep '^Disk /dev'|tail -1|awk '{ print $2 }'|tr -d ':'

should tell me the name of the last disk available to the system, and if it doesn't equal a disk listed in

df|grep '^/dev/'|awk '{ print $1 }'|tr -d '[0-9]'|sort -u

I'm good to go.

Of course, if anyone knows a simpler way of solving the issue, feel free to comment. :-) -- 78.43.71.225 (talk) 13:55, 15 January 2011 (UTC)

Full Screen Games Minimizing On Start

Hey all,

I've got an intermittent problem that's been doing my head in for quite a while. I've looked around on the internet for people with the same issue, and it seems there are many of us, but surprisingly few people (i.e. zero) with the answer. My problem is that when I launch a full-screen game, it minimizes almost immediately, and no matter how many times I click the tab in the task bar, it won't stop minimizing. A restart of Windows generally sorts the problem out. Now, I will anticipate a few of the possible answers I may get:

• Do you have an IM running, as it sounds like something is demanding attention? Yes and no. I have tried playing games with and without an IM running, and I still get the same problem.

• Do you have the latest version of your video card's driver? My driver is updated automatically whenever an update is available, so, yes.

• Have you tried running games in windowed mode? Yes, I have, and this solves the problem. Unfortunately, not all games have a windowed mode (and many of the ones which have won't stay on screen long enough for me to change the settings).

My computer is a G60 Netbook from HP. This problem has only been occurring since October of last year. I recently reinstalled Windows (due to an unrelated issue), and the problem is still happening. Like I say, after restarting Windows, the problem is usually fixed, at least for a few games, before it starts happening again.

Any help would be appreciated. --KägeTorä - (影虎) (TALK) 19:33, 14 January 2011 (UTC)

I have noticed a similar annoying symptom for the last few weeks when playing Civilization IV recently (which I bought on Steam) on my Windows Vista machine. I do task-switch often via alt-tab, and I do play Civ IV as a full-screen game. When I alt-tab back to Civ IV, it will sometimes switch right back to the Windows desktop. I have found that if I alt-tab to Civ IV and quickly click the left mouse button, it won't task switch back to the desktop, and I have assumed there's some errant bit of code somewhere which believes that I've clicked the Windows desktop and it switches me over there; and the Civ IV click stops this behavior. I'd be interested to know if this helps your symptom, too - Comet Tuttle (talk) 23:06, 14 January 2011 (UTC)

It doesn't help - I often click or press escape after re-maximising the game, and I am not sure if it is helping because the game will sometimes minimise itself again and sometimes not. It is pretty frustrating, and seems to happen more with older games (pre-2008), although it sometimes happens with the newer ones too, especially if I've tried to play an older game first and this has happened. I forgot to say I am on Vista. --KägeTorä - (影虎) (TALK) 02:38, 15 January 2011 (UTC)

I have no references for this, but I just wanted to throw out an idea: Could it be that the games are trying to use resolutions not supported by your monitor? Google suggests that the G60 has a resolution of 1366x768 and a lot of older games especially wouldn't support widescreen. Normally I'd expect the monitor to resize accordingly, but maybe that's the problem and it doesn't/can't. Try going into your display settings and changing the resolution to 1024x768 (assuming you can - things will either look stretched or will have black edges) and then try your game and see if it's made any difference?  ZX81  ^talk 15:22, 15 January 2011 (UTC)

Well, the thing is, once one game starts this pallavah, they all start doing it, no matter what the resolution is. A restart will generally sort the problem out. Defragging sometimes seems to help, too. It's only been happening since October or so of last year, and before that I'd never experienced anything like it. Not only that, I can play the same games on my Ubuntu partition (using Wine) and I don't get the problem even once. --KägeTorä - (影虎) (TALK) 20:09, 15 January 2011 (UTC)

Ubuntu

Between Ubuntu variants, is there really any significant difference? And are there any major flaws or advantages of any specific variants (especially version 10.10 "Maverick Meerkat")? Thanks, --T H F S W (T · C · E) 21:31, 14 January 2011 (UTC)

Regular Ubuntu uses GNOME as its desktop environment (with a bunch of associated helper apps); Kubuntu uses KDE instead. Some folks think GNOME is easier to use, or perhaps a bit more like Microsoft Windows, and find KDE a bit techie; other folks think GNOME is inefficient and unconfigurable. In practice almost all applications will run in either environment (as Kubuntu still installs GNOME's underlying toolkit, GTK, and Ubuntu still installs KDE's underlying stuff, including QT). For a full-featured desktop, it really doesn't matter which you use, and if you don't know (or don't care) then just use regular Ubuntu. Xbuntu eschews both for a lighter-weight environment; it's more suitable for older, cheaper, or otherwise more resource constrained environments. Canonical produces a server variant of Ubuntu too; that's really mostly just the desktop one with the graphical stuff removed (and with some changes to configuration to best suit a server environment). But the desktop variant can install all the server stuff, and the server variant can install the desktop stuff, so they're not that far apart. Only use the server variant if you're setting up a genuine dedicated server machine. Beyond that there's stuff for specific purposes (produced by other development teams) like Edubuntu, which are really just regular Ubuntu with a tailored set of applications that come by default. As to versions, there's almost no reason to ever install anything but the latest one. Only people with very specific requirements to deliberately run older software (mostly to keep uniformity and predictability in an enterprise environment) should ever install the older versions. -- Finlay McWalter ☻ Talk 22:28, 14 January 2011 (UTC)

I'd stick with LTS (long term support) releases, if I used Ubuntu. Latest is 10.04, and it will be supported longer than 10.10. If you know what you're doing it won't matter, but it's slightly more insulation. I'm with Finlay mostly, but think Windows users will tend to prefer KDE. Some of the derivative distros are officially supported by Canonical, some are not, FYI. ¦ Reisio (talk) 22:34, 14 January 2011 (UTC)

It'd recommend LTS for an enterprise with hundreds of machines doing mission-critical work, where they didn't want to take the risk (and cost) of upgrading machines to a newer version during their design lifespan. LTS just means they'll continue to get patches on that install for longer. For everyone else, and I'd say for any new Linux user, the newest release is best; Canonical (and the Debian teams that do much of the work) have done a great job in making the last few Ubuntu versions (for at least two or three years) very stable. -- Finlay McWalter ☻ Talk 22:48, 14 January 2011 (UTC)

The idea of using Ubuntu for something mission critical is frankly laughable. I agree, however, that it will only make a difference to the truly uninitiated. ¦ Reisio (talk) 03:26, 15 January 2011 (UTC)

Marnanel (talk) 03:37, 15 January 2011 (UTC)

Ubuntu is a derivative of Debian. Debian is for home or personal use, not mission critical use. The main issue here is that package maintainers are allowed to alter the code for the package as they see fit without sending it back upstream to a main oversight group. For example, the openssl package maintainer removed a random number seed in the openssl package because he didn't think it was necessary. The change was not part of oversight. For over two years, nobody noticed (except hackers). Then, it was discovered that all of the ssl keys in Debian were weak and guessable. All Debian users had to regenerate them. An alternative is something like RedHat. All changes require extensive oversight because it is designed for a mission critical environment. For home/personal use, it isn't very nice because that is not the target market. It all boils down to two markets: Get updates slow but highly secure vs. Get updates right away and find the bugs later. -- kainaw™ 03:58, 15 January 2011 (UTC)

iPod touch Backup

I am running Mac OS X 10.5.8 and I have a 4th generation iPod touch running iOS 4.2.1. I have app data on it that I would like to save. I'm confused about whether or not backing up my iPod through iTunes saves app data because I've read that only certain apps allow for app data to backed up, or it doesn't backup app data, etc. I have James Cameron's Avatar: The Game on my iPod touch and I've gotten pretty far in it and I want sync a couple of recent previous firmwares and iOS 4.3 beta on my iPod touch so I can get their SHSH blobs with Tiny Umbrella. I've looked at the size of the backup created by iTunes and it is only 44 MB in size which seems way too small to have backed up all app data, contacts, etc.

So, I want to know if there is any program out there that I can use (compatible with Mac OS X) that can backup everything on my iPod touch, in a manner similar or the same as flashing the memory (when I say flash I do not mean Adobe Flash or wiping it clean) without a jailbreak? I think it might be theoretically possible by just ignoring file system privileges in the same manner some builds of xpdf can view a PDF document without respecting the DRM. --Melab±1 ☎ 23:22, 14 January 2011 (UTC)

Help would be appreciated. This is time-sensitive. --Melab±1 ☎ 00:37, 15 January 2011 (UTC)

Keyboard shortcut for the back button

In Internet Explorer, pressing backspace does the same thing as clicking the back button, and over many years of using windows I have got very used to this shortcut. At work I use Ubuntu and I find with Firefox the keyboard shortcut is Alt+Left-arrow which requires two hands and is pretty inconvenient (only the left-Alt works and the keys are too far apart to do this with one hand). Several times a day I automatically press the backspace and ponder for a few seconds how much longer it is going to take to go back to the previous page, before I realise I have done the wrong shortcut yet again. Until recently, I though Firefox didn't support changing the shortcut until I came across one that did. Unfortunately, I was in the middle of a training course I didn't have time to check out the settings. So, how do I change the keyboard shortcut for the back button, so it works like Internet Explorer? Astronaut (talk) 22:02, 14 January 2011 (UTC)

Open about:config and change browser.backspace_action to 0. Algebraist 22:10, 14 January 2011 (UTC)

Thanks. I'm not at work now, but I'll check it out. However, the about:config sounds interesting... where can I find out what else I can do with it? Astronaut (talk) 22:25, 14 January 2011 (UTC)

ALT+lArrow and backspace are actually redundant shortcuts, FYI, you don't have to pick just one. IME Linux builds tend to have the backspace shortcut enabled by default, which actually always bothered me personally :P while the Windows builds do not, IIRC. More shortcut configuration: http://forums.mozillazine.org/viewtopic.php?t=72994 ¦ Reisio (talk) 22:30, 14 January 2011 (UTC)

http://kb.mozillazine.org/About:config_entries for starters. ¦ Reisio (talk) 22:27, 14 January 2011 (UTC)

Resolved

Works like a dream. Thank you. Astronaut (talk) 22:09, 17 January 2011 (UTC)

Hotmail has started delivering spam not addressed to me

In the past few days I've been getting a few spam emails in my hotmail inbox which are not addressed to me, but to possibly similar addresses or sometimes addresses which are not at all similar.

Does anyone know why this is happening please? I installed Thunderbird recently, cannot remember if I did this before or after getting the spam, and it could be just coincidence. Thanks 92.15.25.173 (talk) 22:10, 14 January 2011 (UTC)

Just sounds like regular spam to me. Your address is probably on a spam list somewhere, either from a site you gave your address to, or from one of your friend's compromised computers. Astronaut (talk) 22:23, 14 January 2011 (UTC)

It is just regular spam. I get messages (to my hotmail) addressed to someone else quite often, and usually from contacts with hotmail addresses. --KägeTorä - (影虎) (TALK) 22:58, 14 January 2011 (UTC)

I do not understand why Hotmail is sending me things that are not addressed to me. 92.24.180.142 (talk) 23:30, 14 January 2011 (UTC)

Email contains two different parts: the human-readable part, and the machine-readable part. Most email systems do not require that the two actually match. So, it's entirely possible to send mail to user@server.com and place a human-readable "To: Mr. User (joe@otherserver.com)" as metadata. You can read more information in our article, Email#Message header. Specifically read: "Note that the To: field is not necessarily related to the addresses to which the message is delivered. The actual delivery list is supplied separately to the transport protocol, SMTP, which may or may not originally have been extracted from the header content." If this explanation is too technical, you can sort of think of it with this analogy: suppose a spammer sent you a paper letter via regular postal mail. On the outside envelope, he has to put your actual address (house and street number) so the postal service delivers it. But once you open the envelope, the paper letter on inside can be addressed to anybody. It can say, "Dear Aunt Sue," or "Dear Bob"... it doesn't matter. The mail has already been delivered based on the outer envelope address. Nimur (talk) 00:25, 15 January 2011 (UTC)

Many internet security experts consider the original EMAIL implementation to be fatally flawed for this reason (among numerous other problems). There is essentially no enforcement that senders authenticate themselves (they don't have to prove that they are who they claim they are); and there is essentially no requirement that metadata matches reality. See E-mail spoofing for more information. In a sense, "social network" websites sidestep this issue by consolidating every authentication in the entire world into a single login-system, which is operated by one single social network corporation's servers. Email, on the other hand, is distributed, so there is no central authority to verify credentials. Nimur (talk) 00:34, 15 January 2011 (UTC)

Note of course even if you are note in the To:, you may be in the CC: (which is visible) or BCC: (which should normally be removed) Nil Einne (talk) 10:51, 15 January 2011 (UTC)

I'm shocked that as a very very very very....very rudimentary anti-spam device that the Hotmail computers, and the well paid execs there, do not make sure that the emails are delivered only to the human readable address, or at least that emails where the human readable address contradicts the computer readable part are rejected. At the very least there ought to be an option to refuse emails with these deceptive addresses. Is there one?

How can I complain to Hotmail/Microsoft about their lazy sleeping execs who should have already fixed this long ago? You cannot say that the computers cannot read the human-readable email address - that is no excuse. Even the domain name part of the email address has been different. Its really really dumb to deliver something addressed to Pamela Anderson, Hollywood, USA, in the letter box for The Pope, Vatican, Italy. Duh! 92.15.27.244 (talk) 11:10, 15 January 2011 (UTC)

Uh who said computers can't read it? It's just that they don't because they're not supposed to and in fact doing do would likely break some things like Blind carbon copy and most mailing lists. As Nimur has said, you're letter analogy doesn't really work. If I write a letter to Pamela but address it to The Pope on the envelope, it's not the postal service's fault that The Pope receives my letter. Note that even if server did require To:, this would do little to discourage spam since the spammers can easily change their practices here, it's not likely to be much of a hurdle at all. (Things like requiring authentication would likely help more.) P.S. You can of course easily set up a filter to delete, copy to a spam folder or whatever all messages which don't have you in the To: field. You might want to at least consider looking in both the To: and Cc: but it's up to you. Nil Einne (talk) 12:16, 15 January 2011 (UTC)

Who says "the're not supposed to" look at people's emails? Googlemail got bad press about doing this routinely, but just having a computer check that the mail is being delivered to its ostensible address is nothing that anyone, apart from the spammongers, could object to. And its astounding that it hasnt been done from day one. 92.15.24.16 (talk) 14:23, 15 January 2011 (UTC)

Thanks, will look into the filter you described, but it should be the default setting.

Blind carbon copies ought at least to be signalled as such in the human readable part of the email, with an option to reject them. I suppose BCCs must be how spammongers send a lot of their spam out, otherwise it would have the correct address shown.

I'm shocked Hotmail seem to shrug their shoulders at spam and say "Stuff happens" and go back to sleep again. Emails with the wrong address are really shouting out loud with a bullhorn and waving a large flag saying "Hey, I'm spam!" yet nothing is done about it. 92.15.24.16 (talk) 12:29, 15 January 2011 (UTC)

I don't think you can do much, even with the filters. The filters only let you ignore mail from a specified address in the from field, which can also be easily faked. So, you might appear to recieve mail from panderson@hollywood.com and pope@vatican.org, but when you examine the headers and trace back the IP addresses, they actually come from the same place in China (for example). And when it comes to complaining to Hotmail, I wouldn't hold your breath. In my experience, they seem curiously reluctant to get a real person to answer users' complaints and instead rely on a computer sticking different names on form letters. If the spam really bothers you, I suggest you ditch that account and set up new accounts for different purposes (one for family & friends, one for shopping, one for work/school, one for riskier sites such as forums, etc.) Astronaut (talk) 14:35, 15 January 2011 (UTC)

Surely it must be elementary programming to check that ostensible address matches the delivery address. Why don't they pull their finger out and do it? 92.15.24.16 (talk) 14:44, 15 January 2011 (UTC)

Because as pointed out already, that's how Blind carbon copy works and to "fix" this, would break that (and people do actually use BCC for valid reasons). So I can't see them wanting to make a change that would break a feature that a lot of their members probably use/rely on.  ZX81  ^talk 15:17, 15 January 2011 (UTC)

I really cannot see why people cannot understand that I want to reject all emails that are not ostensibly addressed to me. BCC is irrelevant to this: all the software has to do is see if the delivery address is within the ostensible address string, and if not bounce it back - so so simple. I am on a few mailing lists etc and the emails are always properly addressed to me, so even if the use BCC they still have no problems ostensibly addressing it to me. Its a very simple and straightforward request. Its easy to understand - if the ostensible address is not mine, then I don't want it. Whats so difficult to understand about that? I've never had any valid email that's not been ostensibly addressed to my address. I cannot imaginine even the most dim-witted real postman having difficulty with the concept that you only put mail into the letterbox it is ostensibly addressed to. 92.15.24.16 (talk) 18:37, 15 January 2011 (UTC)

Well BCCs don't necessarily have your email address in the header (that's why they're called BCCs...) and as such that's why Hotmail can't just block them without blocking all BCCs. Some emails do contain it, it all depends on the sending server, but as far as I know there's no requirement for the sending server to include it. Since Hotmail is used by millions of people and they have to support BCC I'm afraid your only solution would be to set up your own mailserver and tell it not to accept BCC's, but then if someone tries to send you a BCC you wouldn't get it, nor would you know they even sent it...  ZX81  ^talk 18:54, 15 January 2011 (UTC)

Our article mentions some of the problems with the way what's supposed to be done with Bcc is defined. Nil Einne (talk) 20:18, 15 January 2011 (UTC)

Also, if Hotmail were to make a change like that, it would stop spam for a couple days, and then the spammers would just change what address they send things to. The reason why Bayesian spam filtering works well is that it can react quickly to new spam techniques, and that it also identifies characteristics that make a message likely to be non-spam for a particular user, which spammers can't fake without knowing the recipient's specific interests. Paul (Stansifer) 15:46, 15 January 2011 (UTC)

The point is not sending it to my address. 92.15.24.16 (talk) 18:37, 15 January 2011 (UTC)

They are sending it to your address or else it wouldn't get to you. This should be obvious.

What you're complaining about is that the "To" field does not match your email address. As has been explained above, if an email is sent to you with your address in the "Blind Carbon Copy" field then your email address will not appear on the email. (That's what the "blind" means. A regular carbon copy will show the address of the CC recipient.) There are entirely legitimate uses of this. (Bob want's Joe to have proof that Bob sent an email to Sue, but he doesn't want Sue to know that Joe is involved. So he sends the email to Sue with Joe's address in the BCC. Joe's email address will not appear on the email, but he will receive it.) APL (talk) 08:43, 16 January 2011 (UTC)

Um there are standards (RFC) that email servers are generally supposed to follow and while Microsoft and other companies do sometimes ignore them, in this cases there's no point since as me and others have pointed out, this will cause far more problems for the many people (including mailing lists) who do use BCC correctly, but will cause very few problems for spammers since they can easily change their software and don't give a crap about revealing other people's email addresses or the potential confusion about whether something was sent to a discussion list or sent to a person privately. There have been plenty of proposals which will semi-break the way e-mail works (e.g. hashcash) in an attempt to thwart spam but to be blunt, your one seems one of the more pointless ones that isn't going to achieve anything other then cause problems for those who aren't spamming (probably why you don't tend to here it from those who actually manage these sort of things). Nil Einne (talk) 20:00, 15 January 2011 (UTC)

As for the filters, I don't use hotmail (or webmail products in general) so was just speaking in general terms and apologise for not making that clear. Definitely few decent email programs would have problems setting up filters which would basically discard any emails which don't have your address in the to and cc lines (although with gmail for example where your address can actually take numerous forms it may not be so easy if possible to support all those forms depending on the boolean operators available). I'm quite confident the old Eudora has been able to do this for a long time (probably very 5 or earlier) and from a quick look at Thunderbird it should be no problem there either. If you filters lack a 'not' or 'else' function and also don't follow a defined order (with the ability to end filtering in a given filter) then it probably won't be possible. Nil Einne (talk) 20:09, 15 January 2011 (UTC)

Now they've found your email unfortunately you will get more spam. One bit of free advice - never click on a link in such spam, in particular never click on a link in spam saying you want to be removed from their mailing list. That simply tells them you read the spam and are a more worthwhile target. Dmcq (talk) 21:20, 15 January 2011 (UTC)

If I don't want garbage addressed to other people stuffed into my inbox, then I don't see why I should get it. Why bother whining? Why not simply fix the problem? If that means I never get something related to "BCC" again, then so be it. No more excuses. If a real postman did this, they'd rightly get sacked. 92.29.122.203 (talk) 11:10, 16 January 2011 (UTC)

There's no problem to fix. If you want to violate established internet standards for something that will achieve little, that's your choice and you've already been told of ways you can do it, just don't expect companies who actually think about this sort of thing and so know why it's a bad idea and why it's pointless to do it. And yes why you're whining at us none of which I suspect work for Microsoft because you don't like standards and think they should be ignored for no reason is beyond me. If a real postman decided to open your mail because they didn't trust the address on the outer envelope and didn't deliver the mail because the address inside was different they would indeed be sacked and not just for the privacy violation. (This isn't the best example but the postman analogy is starting to fail and this is the best example I can think of which fits your situation.) Nil Einne (talk) 15:09, 16 January 2011 (UTC)

Of course, spam filtering can be done pretty well. Spam Assassin is a good program that assigns a "score" to an email based on a large number of rules. (If the recipient is only a BCC it penalizes the email a few points.) Then the user can set up their email client to filter out any email below a certain score.

So far as I know, none of this could be done by an end user to a Hotmail account, sadly. But if you ran your own email server you could easily install this software or others like it and control it anyway you like. (And when it threw out an important email that you needed to read, well you could complain to yourself for setting it up, I guess.) APL (talk) 19:11, 16 January 2011 (UTC)

As others have said, the Simple Mail Transfer Protocol, which is how emails are routed to the recipients, ignores the To: and Cc: fields. Please see the example in the SMTP article for how it is actually routed. CS Miller (talk) 15:58, 16 January 2011 (UTC)

Real postmen deliver junkmail that's not specifically addressed to me all the time. Sometimes it's to "Joe Smith or Current Resident", sometimes they give up pretending they know who lives here and write "Our Valued Customer" even though I'm not, and sometimes they don't even put the address. I'm not sure how this works, but you can get the post office to deliver a piece of mail to every resident in a certain area. APL (talk) 19:11, 16 January 2011 (UTC)

Of course, at least where I come from, you can reserve yourself against that. Taemyr (talk) 22:51, 16 January 2011 (UTC)

At least I get to recycle all the spam the mailman dumps though the letterbox. Now if only there was a way of doing that with email spam... ;-) Dmcq (talk) 00:24, 19 January 2011 (UTC)

January 15

Another Flash 8/AS2 question

Frame 3, button 'Fight':

on (release) {
	var ci:Boolean = false;
	var ydie:Boolean = false;
	var ldie:Boolean = false;
	var sdie:Boolean = false;
	yealth = 16;
	lealth = 20;
	slealth = 10
	gealth = 38;
	cin = 2;
	gotoAndPlay(4);
}

After clicking the button, the computer prompts me to stop the script. Why is that? Kayau Voting IS evil 01:29, 15 January 2011 (UTC)

It could be a loop. What's the exact message? Also, what's in frame 4?--Best Dog Ever (talk) 01:42, 15 January 2011 (UTC)

It was something to do with slowing down the computer. Frame four is where the player clicks on the guard to attack him. It goes to frame five, which directly goes to six, where you go either back to frame 4 if gealth > 0 or to frame 7 if gealth = 0. Kayau Voting IS evil 02:26, 15 January 2011 (UTC)

It's really hard to say without looking at the FLA file.--Best Dog Ever (talk) 03:02, 15 January 2011 (UTC)

That is too large to upload on t35. I'll try to find some other way... Kayau Voting IS evil 12:50, 15 January 2011 (UTC)

It's now on The new official site for the game. :) Kayau HAPI B-DAY WP 14:07, 16 January 2011 (UTC)

When I click on the link, I see and error message that says, "Resource not found."--Best Dog Ever (talk) 20:02, 16 January 2011 (UTC)

Whoops! Corrected. Kayau Voting IS evil 01:51, 17 January 2011 (UTC)

ok. Thanks. It looks like the frames you're having trouble with are in Scene 7, right? Well, I played them and didn't see any error messages. I got to the third frame and clicked the button to fight the guard. Then, it went through to the beginning of the game -- Scene one -- since there are no stop actions in frame 4 and it says to go to and play at frame 4. If anyone else is interested in taking a look, you go to Window --> Other panels --> Scene and click on the seventh one.--Best Dog Ever (talk) 22:49, 17 January 2011 (UTC)

Hm, that's odd, because I played it again and still got an error message. Perhaps I could explain what I'm trying to do. What I was thinking is that when the player reaches frame 4, it goes straight to frame 5 (hence nextFrame), and when the player reaches 5 it goes straight to 6 (again nextFrame), and at frame 6 the guard hits, then the player either goes back to 3, if the former slave is still alive, or to 7, if the slave is dead. I haven't added in any code for victory yet, but I don't think I should jump the gun when defeat isn't done yet. Kayau Voting IS evil 10:48, 18 January 2011 (UTC)

Browsing OpenJDK source

Resolved

I'd like to browse the source to a few java source files (e.g. things in java.io and java.lang) of the OpenJDK project. I'd really rather not download the whole JDK source, but rather pick it out of the Mercurial web interface (in the way one can do likewise on the GNU Savannah website). The OpenJDK folks do have links to a Mercurial browser on their website, but the tree it shows only has a few infrastructure things (some makefiles etc.) not the actual JDK .c and .java source. Am I somehow missing this stuff in there, or is that stuff elsewhere (or no-where)? Thanks. 87.113.112.90 (talk) 03:50, 15 January 2011 (UTC)

Ah, I found it (here). -- 87.113.112.90 (talk) 04:28, 15 January 2011 (UTC)

Windows 7 information to XP computer

I have on my main computer XP sp3 and I have downloaded on this computer movies and have them in a download file.I also have a Popcorn hour hooked up to this computer so that I can put all the movies on a hard drive that the Popcorn hour has...then I can play all the movies when ever I want using the Popcorn hour's hard drive and keeping the main computer's hard drive free.

On my laptop which is windows 7 I have movies downloaded but wish to access the Popcorn hour and am not getting much help from these people.

I have got as far as I can and the information I have got from the Popcorn people is for XP not Windows 7.

All my computer and Popcorn Hour are hooked up through a router (hard wired)

I am new at this soooo...please excuse my ignorance on how things work! — Preceding unsigned comment added by Golferknut (talk • contribs) 21:53, 15 January 2011 (UTC)

Golferknut — Preceding unsigned comment added by Golferknut (talk • contribs) 14:23, 15 January 2011 (UTC)

Updating DirectX 9.0

Hello there,

I am trying to get the recent build of DirectX 9.0. Trying to troubleshoot a game, and I have been instructed to get the package from here. However, once this has downloaded, running it I get a dialogue box asking me where I want to put the 'extracted files' - as if I should have any idea - then it gives me 155 .rar files and two .dll's. There is no help at all on that page, and the people who told me to get this package have gone home for the weekend. I have tried installing the 'websetup' version, but that just tells me I already have a later version (maybe this means a later version of DirectX 9.0, or perhaps it is referring to the fact I have DirectX 10 and 11 - who knows?) and won't let me install. All I want to do is update to this latest build. Is there any way I can do this? --KägeTorä - (影虎) (TALK) 15:37, 15 January 2011 (UTC)

If you have a more recent version like DirectX 10 or 11, I don't see why you need to rollback to a previous version.General Rommel (talk) 03:24, 16 January 2011 (UTC)

That's actually not the latest version, for some reason Microsoft never released a redist for November 2010 [1]. But anyway if you don't want to use the webinstaller, choose a directory to extract the files and then run dxsetup.exe. Despite the statement above, no rollbacking should ever happen (even if you run an old version although I wouldn't try an 8 year old version just to see) and the updater should update whatever version you have (10, 11) if it contains an appropriate update. However if the webinstaller is telling you you have the latest version, then you probably have the latest version. Try running dxdiag.exe if you aren't convinced. If you are running Windows Vista, you may want to consider installing DirectX 11 if you haven't already, see [2]. Nil Einne (talk) 15:04, 16 January 2011 (UTC)

Database backup

How do the Wikimedia database dumps work? How do you make a copy of a database that is constantly being modified? 70.162.9.144 (talk) 18:28, 15 January 2011 (UTC)

Backups are performed using the DumpBackup.php tool, which in turn uses Export feature of Mediawiki. In essence that does a giant SQL query on the table(s) being dumped. As things are being simultaneously updated all the time on the live Wikipedia (etc.) site, there's no particular guarantee that the resulting dump will be entirely logically consistent. 87.113.112.90 (talk) 19:00, 15 January 2011 (UTC)

— I have never done this; but 87's link is bad, and the problem of getting a copy of a database that's constantly being modified was solved decades ago; a database dump doesn't just do a byte-for-byte copy like your OS does when copying a file, but copies the database as it existed as of a certain timestamp. I don't see an article specifically about this topic, but our backup article refers to databases several times. Comet Tuttle (talk) 19:06, 15 January 2011 (UTC)

The page is here. The core backup code itself is in Export.php in the mediawiki distribution. 87.113.112.90 (talk) 19:13, 15 January 2011 (UTC)

The database transaction article is relevant, I think. Computer file systems are databases too. They often lack transaction support, but that's because operating systems suck. Windows finally got transactional NTFS with Vista. Shadow Copy allows you to mount a snapshot of the filesystem for backup purposes (the better backup programs use this behind the scenes). Applications and services are notified just before the snapshot is made so they can flush unwritten data and make the disk more-or-less consistent. -- BenRG (talk) 19:17, 17 January 2011 (UTC)

See this section of WP:DUMP. It is explained that the enormous size of the Wikipedia database is so huge that modern MySQL servers sometimes fail to work correctly. "The dump process has had difficulty scaling to cope with the size of the very largest wikis, and as a result the system failed for several years to produce valid, complete dumps of the English-language wikipedia. Even now, the system struggles to create valid dumps." So, even with the established techniques that should guarantee logically-consistent timestamped database copies, "implementation errors" in MySQL (and the surrounding web application frameworks provided by MediaWiki and the toolserver) currently are not capable of producing correct and logically-consistent copies for a single timestamp of the 20+ terabyte English Wikipedia back-end database. Nimur (talk) 19:17, 16 January 2011 (UTC)

Acrobat Reader X monitoring pdf files - how to stop?

Whenever I pass with my mouse over a .pdf file, AcroRd32.exe appears in Windows Task Manager and is doing something for a second or two... It seems there's some process or program monitoring .pdf files for mouseover. How this could be stopped? —Preceding unsigned comment added by 109.66.7.118 (talk) 18:34, 15 January 2011 (UTC)

I think this is somehow similar with the way .avi files are treated - the system adds additional info about them in a special tab of File Properties, so probably each time you hover the cursor over the file the system has to update this info so Acrobar Reader is called. This treatment of .avi files can be remedied by registry hack - something in HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Ext\Settings As to .pdf files, I don't know... Maybe somebody else could help? 213.8.52.97 (talk) 09:45, 16 January 2011 (UTC)

There's a tab named "PDF" in File Properties of every .pdf file. So this really could be the reason behind Acrord32.exe activities - it is probably updating info in the tab. The question is - how to disable this? 109.66.7.118 (talk) 15:38, 17 January 2011 (UTC)

Disable the Adobe Reader add-on in your browser. Here's the process for Internet Explorer: [3] and here's the process for Firefox: [4]. Also, open Adobe Reader, go to Edit --> Preferences --> Internet and uncheck "Display PDF in browser."--Best Dog Ever (talk) 10:02, 16 January 2011 (UTC)

The add-on is disabled and "Display PDF in browser" is unchecked. So these settings are not related 109.66.7.118 (talk) 15:21, 17 January 2011 (UTC)

Ubuntu dual-boot troubles

I just made a new Ubuntu 10.10 Netbook Edition Live CD using Linpus Linux for the Acer Aspire One with Intel Atom and Windows Vista for an Acer Desktop PC (I don't know which, with some kind of AMD chip, I don't know which). I downloaded the .iso Ubuntu disk image using Linpus and burned it onto the CD-RW (700MB as required) using Vista.

Now, the CD seems to work fine, but when I try to boot without installing I get messages like: 'GLiB warning: getpwuid_r(): failed due to unknown user id'.

I've tried looking for help, but I don't understand all this gobbledygook. Could some kind soul tell me what to do using minimal jargon and how to do things in specific, non-vague terms, please? I really want to replace Linpus and I could use the help. Thank you very much for your time.

These are the two places I looked for help: [5] and [6]

--Editor510 ^{drop us a line, mate} 20:57, 15 January 2011 (UTC)

I dual-boot a variant of Ubuntu. While this answer may not help much, I get that error everytime (not from the CD, but from my drive partition) I boot, and so far as I know it has not caused me any problems. I have no idea what it is talking about, but I would be interested in finding out. It isn't stopping it from booting is it? Falconus^{p t c} 04:43, 16 January 2011 (UTC)

Well, it freezes up at the Ubuntu logo. Could it be the CD drive? If it is, that means the CD I spent ages making is useless.--Editor510 ^{drop us a line, mate} 18:51, 16 January 2011 (UTC)

This error message, by itself, doesn't provide enough information for us to fix the problem - but we're close. I'll try to explain the root-cause of the error in general, and in the hope that it may hint at finding solutions for your specific case. It is the convention in many Linux/Unix operating systems Debian (and therefore in Ubuntu) that certain system processes, called daemons, have their own user account. For example, a web server (which is a standalone program that is running at all times) may log in to the computer as WebServerUser. This makes it easy for the operating system to know when Web Server accesses files; it is trivial to guarantee that file-permissions are correct (simply deny access to blocked files for the entire web server login account). Similarly, other system processes (such as certain hardware drivers and some software abstraction layers) also have their own user account. If you see an error like GLiB warning: getpwuid_r(): failed due to unknown user id, the actual problem is that a system service can not start. It was probably configured to use its own login-id; and later system-setup may have removed that login-id (without uninstalling or reconfiguring the program that expects to use it). If the daemon isn't critical, your system boots as normal and you barely notice anything. But if that was a needed system tool, the program can't start, and the boot halts. So, to fix this problem, we need to know exactly which user-id is being sought, and by which daemon. We need a more complete printout of the error-message you are seeing. Then, we can give you specific instructions to uninstall, remove, or repair that specific part of the system that is failing. Can you give us more of the error message (any text surrounding it)? Nimur (talk) 19:25, 16 January 2011 (UTC)

It also says 'mktemp: error while loading shared libraries'. Does that mean anything to you?--Editor510 ^{drop us a line, mate} 21:38, 17 January 2011 (UTC)

mktemp is another system utility; it is documented here. Again, we still do not have enough information to determine the root-cause of this problem - almost any program may use mktemp to set up temporary configuration. Can you determine which program is failing to start from the error-log, or can you post the entire error log (at least, the last few complete lines)? Nimur (talk) 23:20, 17 January 2011 (UTC)

irc://irc.freenode.net/linux ¦ Reisio (talk) 15:11, 17 January 2011 (UTC)

January 16

How to keep sockets alive in Java

Hi! I'm developing a Java program between a client and server. Both sides have a thread blocked reading for long periods of time. The problem is I get a SocketException: socket reset after about 5 minutes of not writing on either end of the socket. What's the easiest way to fix this? I'm thinking about writing a nonsense byte to the socket at regular intervals to keep it alive, but that might take some recoding so that it can be recognized and discarded by the reading end. I tried setSO_KeepAlive(true) before connecting the socket, which didn't solve the problem (does it have to be set to true on both ends?). Interestingly, if I run the client and server on a local network, there is a longer interval of inactivity before I get a SocketException: socket reset, but over the Internet it's only about 5 minutes. Anyway, I'd greatly appreciate any solutions or suggestions. Thank you!--el Aprel (^facta-_facienda) 02:48, 16 January 2011 (UTC)

Could you specify some versions?Smallman12q (talk) 05:08, 16 January 2011 (UTC)

I suspect you have a router/firewall that is messing with connections. See if you can configure it not to be so aggressive. Failing that, implement your plan of periodically sending a "nonsense byte" (technically known as an application protocol heartbeat). TCP keepalive does a lower level heartbeat, but the interval of keepalives is of the order of a couple of hours, and there is no API for changing it (operating system level hacks for changing it may exist, but I suggest not going there). 88.112.59.31 (talk) 13:23, 16 January 2011 (UTC)

Of course, to answer this correctly, we need to know why the Socket is timing out. Sockets don't "die" unless something kills them - usually a firewall. Is there an intermediate firewall between the computers that are communicating? Is either end-point's network driver, operating system, or software-firewall killing the socket after a certain period of inactivity? The answer "depends" and it may be impossible to find out unless you control both endpoints (and all network connections between them). A reasonable workaround is to assume that somebody's firewall is going to kill your socket after some delay. (30 seconds is a common network inactivity timeout on many firewalls with default settings). So if you send a "heartbeat" every 20 seconds, you keep most network connections alive. That heartbeat can be anything (you're programming the server and the client software, right? So just design a "NO_OP" magic byte, or packet, or whatever. Alternatively, for an even safer, more-robust workaround, (that doesn't make any assumptions about firewall-timeout rates), design your network code to be resilient in case of dropped-connection and provide for both client and server to attempt an automatic reconnection using a new Socket object. Note that the SO_KEEPALIVE implementation for Java Socket has a hard-coded time-period of approximately 2 hours (for OpenJDK and Sun's JVM implementations); this is much longer than most firewall timeouts, so you'll need a homebrew solution. Nimur (talk) 23:31, 16 January 2011 (UTC)

Thanks! I implemented a heartbeat at 20-seconds interval and it's working as expected.--el Aprel (^facta-_facienda) 04:21, 18 January 2011 (UTC)

The application was unable..

After installing Lunascape browser, I tried to run it. But instead of opening, suddenly a message poped up and said, "The application was unable to start correctly (0xc0000022). Click OK to close the application". I reinstalled the browser but nothing happend except that weird message. It happened several times with another browser like Flock. Mozilla runs fine. How can I fix it?--180.234.45.42 (talk) 11:12, 16 January 2011 (UTC)

• I had same problem with this browser. Follow these steps: Right click on Lunascape shortcut then go to properties. Click on the shortcut tab, there again click on advance tab and choose "Run as administrator". If the shortcut icon does not appear to be Lunascape, you can change it by clicking on "Change icon tab". Then click OK to close the window. You are done. Same process goes for Chrome browser as well. The problem occurs due to the corruption or missing of Shell 32.dll file. I hope this would help.--NAHID 00:29, 17 January 2011 (UTC)

iPhone to monitor streaming

Is there a way I can stream video (Netflix) from my iPhone 3G to my computer monitor via the Apple-provided USB cable? The OS is Windows XP. Thank you161.165.196.84 (talk) 11:22, 16 January 2011 (UTC)

Find word and beep

Resolved

I've been searching for a program (for Windows 7) which can scan a url for a word or phrase, and beep or play a sound if it finds it. So far I haven't found anything which meets all the requirements, so I am now trying to make a script myself using .bat which can do this. So far I have wget which can download the url to a file. Now I just need the 'scan for keywords and beep' component. I've tried find (command) and findstr but they don't beep or play a sound. 82.44.55.25 (talk) 13:59, 16 January 2011 (UTC)

find is your friend, when combined with && echo ^G. Note that the ^G part is entered as [Ctrl]+G.

find "thisiswhatimlookingfor" fooobar.html && echo ^G

-- 188.105.132.219 (talk) 14:04, 17 January 2011 (UTC)

Thank you! :D 82.44.55.25 (talk) 14:24, 17 January 2011 (UTC)

electronics (ripple)

The percent of ripple for a high-quality power supply is supposed to be 5%. If it is a 12v dc power supply, what is the max amount of ripple you should expect to see at the output. —Preceding unsigned comment added by 98.215.204.87 (talk) 14:35, 16 January 2011 (UTC)

This probably should have been asked on the science desk. However, the answer is 5% * 12V. Our ripple (electrical) article should cover the measurement of ripple, but neglects to. CS Miller (talk) 15:49, 16 January 2011 (UTC)

Seeking Basic program code to copy folders and files

I have tried seaching for the code for a BASIC program or routine to copy files and folders (including recursively) in Windows, but have not found anything. I would like to be able to overwrite a folder and its contents with the same folder from somewhere else, except that in the event of a file-name collision I want to modify it so that it renames the new file (eg "myfile001") instead of overwiting with it.

Does anyone know of any freely available BASIC code please? I am using WinXP. Thanks 92.29.122.203 (talk) 15:17, 16 January 2011 (UTC)

What BASIC interpreter are you using? This sort of thing would be much easier if you used something with a more robust file handling library, like VB's File System Object. If you use just BASIC, you'll have to re-invent the wheel a few times, because its file handling functions are pretty simple by comparison. --Mr.98 (talk) 15:21, 16 January 2011 (UTC)

I will use any Basic that is freely available. 2.97.211.3 (talk) 19:15, 16 January 2011 (UTC)

Would you accept VBScript as a form of BASIC? There's a file handling example in the article which you can try out right now. Copy and paste into notepad, save it and rename it to end in .vbs (making sure you can see file extensions in general, so you don't get a hidden .txt after the .vbs). Then double click it to run. If this is the sort of thing you're looking for, I'm sure further hints for how to modify it to copy files will be forthcoming. 81.131.51.219 (talk) 00:24, 17 January 2011 (UTC)

Unfortunately VBScript would be too diffcult for me to be able to use myself. There are many other variants of basic, including those listed here: http://www.thefreecountry.com/compilers/basic.shtml The most difficult thing would be traversing all the sub-directories. Thanks 92.28.254.64 (talk) 00:40, 18 January 2011 (UTC)

SmallBASIC has a DIRWALK command, so assuming it can copy files I will have to figure out how to use that. 92.28.242.93 (talk) 13:51, 18 January 2011 (UTC)

insert copyright into a digital photo

How can I insert copyright information into a digital photo file? Bubba73 ^{You talkin' to me?} 17:05, 16 January 2011 (UTC)

Depends what you would like to do - do you want any inscription to be visible in the photo, or do you want to add a copyright notice to the metadata of the file (the EXIF information)? --Ouro (blah blah) 17:51, 16 January 2011 (UTC)

Are you asking about a digital watermark? If so, most advanced image manipulation programs (such as Photoshop) should have a "watermark" function. -- 174.21.229.4 (talk) 19:52, 16 January 2011 (UTC)

I do not want it to be visible over the photo, so I want to put it in the metadata. I have Photoshop Elements version 6, but I couldn't find how to alter the metadata. (But that is when I was looking for "copyright".) Bubba73 ^{You talkin' to me?} 22:41, 16 January 2011 (UTC)

I hope you appreciate that it is a simple matter for someone to modify the metadata or remove it completely? Astronaut (talk) 23:19, 16 January 2011 (UTC)

I thought it might be. Bubba73 ^{You talkin' to me?} 02:11, 17 January 2011 (UTC)

You can alter the metadata in Windows XP in the windows explorer, if you right click the file and select properties summary advanced, scroll down to comments, keywords section, you can click on the value part and change this. Graeme Bartlett (talk) 04:13, 17 January 2011 (UTC)

If what you are looking for is secure digital rights management software — e.g., an electronic "lock" that will keep people from using your photo in ways you don't want them to — well, it doesn't exist at this point, and might never. (The only things which have the slightest chance of enforcing said restrictions are devices where they are hard-wired into them, like iPads and Kindles and things like that. But general purpose computers will probably always be capable of evading such things.) You have basically three options. One is to write your copyright info on the photo itself in an obnoxious way that will at least make it obvious to everyone (e.g. with a visible watermark). It detracts from the photo that way, but is hard to get rid of. You can write our copyright info on the photo in a hidden way (with a digital watermark or in the EXIF data) but that won't really stop anyone from doing anything with it. The third and perhaps more standard way is to put your website info on the photo at the bottom in a way that is not so ugly that whomever will use it will just snip it off. Then you only distribute a relatively low-resolution version of the photo — one that would look OK on the screen, but not in print. Then you just hope that if people do distribute it around, at least you'll get credit for it, and if someone actually wants it for a purpose that could bring revenue back to you, they'll feel obligated to get in touch for the higher resolution version. If your only goal is controlling how it is used (and not, say, making sure you get credit or driving revenue), then you'd better not put it on the internet at all. There are ways to try and make it harder for people to download, but all you have to do is take a screenshot and those are completely subverted (and believe me, I do that kind of thing all of the time, myself!). --Mr.98 (talk) 14:54, 17 January 2011 (UTC)

If you don't want it to be visible on the image, you should put it in the metadata. People can then edit it, but it will still be copyrighted. The way to edit metadata depends on the type of file you are working with. If it is a Jpeg file, the metadata is usually in the form called EXIF, which you can read and alter in PhotoShop, or, as mentioned above, even in Windows Explorer. If you want to hide evidence of the copyright inside the file, you may have to explore a technique along the lines of digital steganography. Looie496 (talk) 18:03, 17 January 2011 (UTC)

I have Photoshop Elements 6, but I can't figure out how to edit the data. It is a TIF file, though. Bubba73 ^{You talkin' to me?} 20:03, 18 January 2011 (UTC)

I don't see how to do it in Windows Explorer either (i.e. right-click on the file name.) Bubba73 ^{You talkin' to me?} 20:07, 18 January 2011 (UTC)

Free video surveillance software.

My car has been broken in to 1 to many times, Id like to build a video surveillance system using my web cams and my extra computer. i have been looking for a free piece of software that fits my criteria, which is as follows:

• Free.
• Windows or linux based.
• Time&date stamped video.
• 24/7 video&audio recording.
• Ability to delete old video after a set time, i.e. delete videos after 1 week.
• supports my USB cameras at their full resolution (1280x1024).
• record at more than 5fps.
• ability to handle 3 cameras.
• Ability to save video to an external drive.

If anyone knows any programs that fits my wish list please let me know. Only program that i have found that comes close is eyeline (records and 1/2 fps), and zoneminder (doesnt directly support my cameras). Please don't provide random links to webcam software that you found on Google. I know how to use Google. Please only include software that you definitely know has the feature mentioned above. kthxbai 98.208.63.16 (talk) 19:41, 16 January 2011 (UTC)

As a side note; id like to point out that i dont want motion detection based recording, it would be nice if this program would id when motion happened, but not base weather it records or not on motion. kthxbai 98.208.63.16 (talk) 20:02, 16 January 2011 (UTC)

3 high-def usb cameras on one computer sounds iffy. The other stuff seems easy. Can you use 3 computers? It is pretty easy to scrounge old laptops these days. 67.122.209.190 (talk) 10:35, 17 January 2011 (UTC)

GPhoto allows you to write command-line scripts (or compile your own programs, if you know how), and interface with almost any USB-enabled web camera. Using this tool, you could set up photo or video with whatever settings your camera(s) support. GPhoto has thorough documentation so you can check if your camera is supported. Nimur (talk) 21:11, 17 January 2011 (UTC)

Theoretically possible to browse iDevice file systems without jailbreak

Is it theoretically possible to browse the system partition of an iPhone, iPad, or iPod touch without jailbreaking? Say, for instance, a program that will simply ignore the access restrictions since the device would not be running? --Melab±1 ☎ 22:58, 16 January 2011 (UTC)

"Theoretically", every piece of stored information could be accessed or analyzed somehow. If the digital data is represented somewhere as digital data in an electronic circuit, something could strobe through and copy all of it; and then at worst, you'd have to decrypt it.

In practice, though, you're kind of out of luck - let me explain why. "The device is off" is not quite an accurate description of the situation when your PC is connected to an iPod or iPhone. In reality, a chip (possibly the iPod's main CPU, or possibly a peripheral microcontroller only responsible for USB transfer) negotiates all data transactions with the USB host (your PC). USB protocol is quite complicated; briefly summarized, the iPod's controller sends a set of metadata that "publishes" all the standard USB features available. One of these features is a USB mass-storage device class - a software abstraction of a "hard-drive"-style block of data. There are many other software abstractions - sometimes the same data on the iPod is represented through multiple different USB classes (allowing you to access stored mp3 files through the proprietary interface, or to treat them as raw files, and so on). But in all cases, the transactions are mediated through the USB client controller (which runs software on the iPod and is out of your control - you can't "reprogram" it. (Well, "jailbreaking" might help - I'm not familiar enough with iPods to know whether jailbreak firmware also opens up the peripheral USB controller firmware, which may be entirely separate hardware). So if the USB client processor wants to deny access to anything, including the iPod's main flash memory or NVRAM or system area (or whatever other name they choose to call their proprietary nonvolatile storage), you're sort of out of luck. You'll have to (again) reverse-engineer their USB stack, re-program that controller (which may or may not be the main iPod CPU), and then you're free to access anything physically connected to the USB bus.

Let me re-emphasize - all of this is possible - and you can bet that some engineer(s) at Apple know how to do it - but it is not currently realistic to reverse-engineer this stuff by brute-force. In my opinion, any "chance" jail-break by a "17-year-old Russian hacker" is a flimsy cover-story for software tools that got leaked by a disgruntled ex-Apple engineer. As yet, no "17-year-old Russian hacker" has yet "brute-force reverse-engineered" the iPod USB controller firmware. Nimur (talk) 17:04, 17 January 2011 (UTC)

In closing, and at the risk of becoming a rant, let me just say: this is why your effort to reverse-engineer an iPod is futile. Just pick a more standard embedded development board. Sure, iPods are nice and small and the form-factor is cool; the screen is pretty nice; but otherwise, their functionality is equivalent to any other off-the-shelf hardware - only, the Apple electronics are designed by a team of skilled engineers so that they are extremely difficult to modify. They use non-standard pin-outs, non-standard cable connectors, non-standard software, and so on. If you want to work on those electronics, you essentially need to be working inside the Apple development shop in Cupertino - with their specific software and hardware tools, domain-expertise, and so forth. Other commercial hardware is just as good as an iPod's - but doesn't try to road-block "unofficial" developers at every other step. Nimur (talk) 17:10, 17 January 2011 (UTC)

Well, I was talking about iOS devices (i.e., the iPad, the iPhone, and the iPod touch). I believe that normal iPods can be browsed in their entirety. The thing with iOS devices is that software like iPhone Browser or Phone Disk can access the "media" partition. The NAND chip is what contains the media partition and also contains the root partition which I think contains the preloaded apps, such as Notes and Mail, and all of the system files. In the case that someone does jailbreak their iOS, they have full read/write access to the root partition. So with this mind I am wondering if gaining access to the iOS device's root partition could be possible by writing a program that ignores file permissions. --Melab±1 ☎ 22:21, 17 January 2011 (UTC)

And all this would be using the cable that comes with the iOS device. --Melab±1 ☎ 22:22, 17 January 2011 (UTC)

Let me rephrase more succinctly: when you connect via the default cable, your computer is communicating with a USB Client processor on the device - not directly accessing the NAND chip. Any file permissions are enforced by the USB client (on the device) - so to "override" those permissions, you need to reprogram the device's USB controller. That may also require reprogramming the device's main CPU. Here are the official USB specification documents if you want to try to implement or reverse-engineer the device's communication protocol. Keep in mind that additional software protocols ride on top of that layer: here's information on Apple File Connect service, including an "afc2" replacement service that seems to be used by jailbreakers. That information looks out-of-date, though. If the USB controller denies you access to hardware at the protocol level, no amount of "software workaround" will permit access. Nimur (talk) 23:30, 17 January 2011 (UTC)

January 17

android tablets

I notice there are a zillion cheap android tablets sprouting up everywhere, whose hardware looks rather nice. They mostly run Android 2.1 and have vendor-customized UI's and applications, which I presume is like the usual dreck situation from the PC world. Is it likely to be a big problem to root the device and upgrade to a newer version of android, i.e. do they tend to depend on proprietary device drivers and that sort of thing? I'm not trying to plug a particular vendor but one device I'm looking at is here. There are also a lot of even more generic ones at the usual no-name schlock shops. Any thoughts? 67.122.209.190 (talk) 09:58, 17 January 2011 (UTC)

Wikipedia has an article about Android (operating system). The main concern for a potential customer will be whether the tablet vendor will be still around during the life of the product and we cannot predict that. Cuddlyable3 (talk) 11:45, 17 January 2011 (UTC)

Given the zillionness, surely one or two come without root disabled. ¦ Reisio (talk) 15:13, 17 January 2011 (UTC)

Well, rooting (android-speak for what iphone users call "jailbreaking") generally is not something that vendors intentionally "enable". It's a question of how thorough a job they do preventing it. Rooting per se is usually not too difficult. What I was wondering was about the difficulty of installing new versions of android completely from scratch. 67.122.209.190 (talk) 18:00, 17 January 2011 (UTC)

I was semi helping someone look in to Android phones once. What I gathered was that porting a new version of Android is generally quite difficult because many/most? vendors don't release the code for their drivers. In particular, most user lead ports we came across didn't seem to get very far. More common appears to be unofficial beta releases of official lead ports. These were with relatively cheap devices and as I said with phones, so YMMV Nil Einne (talk) 20:59, 18 January 2011 (UTC)

Old laptops

In an above thread someone said "It is pretty easy to scrounge old laptops these days." I was going to reply in that thread, but I didn't want to distract from the OPs question. So, is it really that easy? Where do I need to go to find old laptops for free or really cheep? And how old are we talking, Windows 95/XP? 82.44.55.25 (talk) 10:54, 17 January 2011 (UTC)

Organizations have what is known as a replacement cycle. For laptops it is between 3 and 5 years. Different organizations have different disposal policies. Example You just need to ask about. A scratch-each-others-back arrangement often works -you just have to find out who's back needs scratching. Knowing how to wipe the drives might get you an intro into a little company who does not want their customer and banking details ending up in Nigeria nor China.Offer to run DBAN on it to wipe the data, and then upgrade it by installing a Linux distribution on it.--Aspro (talk) 11:19, 17 January 2011 (UTC)

The OP is located in UK where there are many small shops that sell and repair PCs. They are likely to have many old laptops that customers have had replaced or hoped (probably in vain) to trade in, and which are now virtually unsaleable. Ask around. Cuddlyable3 (talk) 11:34, 17 January 2011 (UTC)

Try eBay, especially searching for the area near yourself to avoid paying postal charges. Old computers are quite often given away on Freecycle or Freegle, but I've never seen any laptops and there are a lot of people keen to have them. If you think the operating system is too old then you can always replace it for free by one of the many Linux operating systems. 92.15.8.13 (talk) 13:37, 17 January 2011 (UTC)

It's also much simpler to "scrounge" up brand spanking new laptops these days, as they are significantly cheaper. You can get netbooks with everything but an optical drive for $100 (€75, though realistically probably also €100). ¦ Reisio (talk) 15:18, 17 January 2011 (UTC)

For buying cheap old laptops from strangers with actual money, try craigslist.org if you're in a reasonable sized city (they have several sites in the UK). It's basically a classified ad service for local buyers and sellers, so you get to examine the merchandise and buy it in person (avoids some scams, and avoids expensive shipping for heavy objects like laptops). But it's often possible to scrounge them for free or for some informal barter, as people are always upgrading laptops, or these days replacing them with smartphones. 67.122.209.190 (talk) 17:57, 17 January 2011 (UTC)

I am fortunate to know someone who runs their own consultancy business and regularly replaces their laptop. I am also know within my family as the person to come to with computer problems. Therefore it was no surprise I was given 3 old laptops only last year:

• The oldest was a small Sony Vaio from around 2000 with 20GB drive, 128MB of memory, and a docking station containing a DVD drive, various ports and a wireless internet PC card. Windows XP and Microsoft Office were installed, but the battery was worn out and the screen hinge was damaged (but easily repairable). I reinstalled Windows using my Windows XP OEM disk and re-authenticated it over the phone. It now works well for light websurfing and using Office, but really needs more memory (a £25 upgrade).
• The second was a 15" Toshiba A10 from around 2003 with a 30GB drive and 256MB of memory. Windows XP and Microsoft Office were installed, but the hard drive was dying. The battery was also worn out and the keyboard had a couple of dead keys. I upgraded the memory and replaced the hard drive with spares (from yet another dead laptop I was given a year earlier) and reinstalled and re-authenticated Windows, though I was unable to save the Office installation. I can get a new keyboard on eBay for about £15 though a new battery is harder to find.
• The last was a HP machine from around 2006 with a 40GB drive and 256MB of memory. Again Windows XP and Microsoft Office were installed, but the previous owner had completely trashed the installation by attempting to upgrade to Vista. Unfortunately, the battery is the worst of the three but can easily be replaced for about £50. Other than that, it is a good and quite fast machine. I could have reinstalled Windows, but instead chose to install Linux for another project.

Yes, old laptops are quite easy to obtain, particularly if you have contacts, but you have to be prepared to put up with a number of issues and recognise the machine's inherent limitations (slower CPU, not the latest screen technology, no built-in wifi, etc.) You should also be comfortable with replacing parts, canibalizing other broken laptops for parts and/or spending a little to fix something. Astronaut (talk) 22:01, 17 January 2011 (UTC)

I'm curious about you saying "I reinstalled Windows using my Windows XP OEM disk and re-authenticated it over the phone". Was that the disk that came with the Sony Vaio you were given, or was it some other computer's disk? If the later, how did you get through the asuthentification process exactly? I would have expected problems in those circumstances.

If the OP wants to tinker with second-hand computers, then I'd recommend doing it with towers or desktops rather than laptops. The parts for the former are much easier to get and to fit, as they are largely interchangeable, while I understand that laptop parts are brand-specific. When I've renovated an old computer, the only difficult thing is working out what particular memory to order to give it the most possible memory. If you replace the old operating system by a free new one, which is easy to do if you can burn a CD, then you do not have to fiddle with updating the drivers or removing the clutter of the previous user. I think upgrading the BIOS is best done in Windows though. 92.28.254.64 (talk) 23:52, 17 January 2011 (UTC)

When you buy a new laptop, it usually comes with Windows preinstalled and a Certificate of Authenticity (CoA) stuck on the bottom. If you are lucky you also get a Windows installation disk, but increasingly common is a means to burn your own installation disk (something you are encouraged to do early in your ownership). That is a normal OEM disk, but it is usually tied to a specific PC manufacturer and (supposedly) cannot be used to fix a different manufacturer's PC. Microsoft also supplies two other types of Windows installation disks: retail disks that you buy in a shop; and generic OEM disks that are supplied to smaller PC makers. These generic OEM disks are distinguished by a large hologram on one side and are not tied to a particular manufacturer. The physical disks themselves are almost worthless without the all important CoA. PC manufacturers buy CoAs and stick one to each PC they preinstall Windows on.

Because all the old laptops had no installation disks but did have valid CoAs stuck to their bottoms, I was able to pursuade my local PC parts & repair shop to sell me a copy of their generic OEM installation disk for the cost of the media and their time (ie. £5!), something that almost certainly won't work with a large retail store like PC World. So, while my Windows XP OEM disk doesn't have a large hologram on it, it is a copy of one that does. Whilst I am unsure of the legality of the repair shop selling me a copy of their installation disk, they didn't sell me a license to use Windows just a means to reinstall one for which I already have a license. Remember, it is the number on the CoA (on the bottom of the laptop) that is used to authenticate the Windows installation.

During the Windows installation, I simply read the number off the CoA that was stuck to the bottom of the laptop. When Windows Genuine Advantage leapt into life and told me I had to authenticate Windows, I simply followed the instructions on screen. Because most of the hardware was the same and the product key from the CoA was the same as the previous installation, the authentication code matched that already recorded my Microsoft. Astronaut (talk) 01:06, 18 January 2011 (UTC)

There are a lot of cheap (eg £5) brand-new Windows XP instalation disks available on eBay. As far as I recall without finding the disk, they are labelled as being for Compaq computers I think. Do you think i could do the above with them? It is also possible to find the liscencse number on the disk even if you do not have a label. Some software called "jellybean" is one of the programs that can retrieve it. However, I intend some day soon to switch to a free operating system, and thus leave all these worries behind me. 92.28.254.64 (talk) 01:22, 18 January 2011 (UTC)

I would be very careful unless you happen to have a Compaq PC which is a close match. These are probably the normal OEM disks (ie. not the generic OEM disks with the hologram) and therefore cannot be used in the way I describe above. If I understand correctly, there are only three kinds of disk - retail, normal OEM, and generic OEM. The product key is not held on the disk and therefore cannot be read - you do need the Certificate of Authenticity. The Jellybean product you mention, reads the registry of an already installed Windows OS, and tells you the product key - useful if your CoA is missing or illegible, but it won't crack a CD and magically give you a valid product key.

If you are going to buy a used laptop, I would insist they show it working and provide you with everything they have, including the installation disks. If you are just given a laptop, you can try to refurbish it but you still might end up having to dump it. I was lucky with the three I was given, getting them all working with a mixture of spare parts I already had and being able to buy an OEM installation disk for minimal cost. But I was quite prepared to strip them all down for parts - which would have been useful had I decided to go ahead and do PC repairs in my spare time. Astronaut (talk) 02:20, 18 January 2011 (UTC)

This may be of interest: http://www.technibble.com/how-to-tell-what-type-of-windows-xp-cd-or-license-key-you-have/ The disk I have, still unused, may be Dell and may have a liscence sticker on it as far as I remember. Knowing the liscence number found by Jellybean may be of use if you want to re-install. 92.28.254.64 (talk) 03:39, 18 January 2011 (UTC)

Problem with number rounding error

I've written a short program in GWBasic that involves adding up two numbers to check that they exactly match another number. If it finds a discrepancy, it stops. The program processes several sets of numbers correctly, but stops when it has to add 1210.42 and 174.65 to check if their total is the same as 1385.07. It says the numbers are different, when actually they are the same.

The two numbers both display on the screen as 1385.07, but when I subtract them and multiply the result by 100 I get a value of "-1". When I multiply by 10000 I get "2". I suppose the problem must be due to rounding errors and binary representations of decimal numbers.

What can I do to fix this problem please? Thanks 92.15.8.13 (talk) 13:28, 17 January 2011 (UTC)

In GWBasic probably not much. Can you rescale your problem so that only integer numbers appear? In your example, just multiply all numbers by 100, add up, compare. In general, if you deal with arbitrary decimal expansions, floating point is in nearly all applications the most convenient format, but in that case you must expect and learn to live with rounding errors. There are numbers with a finite decimal representation that have no finite binary representation, so that rounding is almost unavoidable. Why do you need an exact match? If its a science problem, your inputs are not constraint to arbitrary precision. If its financial, you are only interested in full cents (or whatever the smallest currency subdivision is). --Stephan Schulz (talk) 13:41, 17 January 2011 (UTC)

Will try calculating with pence, not pounds. Is there a way of telling GWBasic that these numbers are integers only, and if I do that can I expect it to ignore any hidden fractional part? 92.15.8.13 (talk) 13:51, 17 January 2011 (UTC)

[7] You type a % after the variable name. 81.131.45.34 (talk) 14:22, 17 January 2011 (UTC)

(ec):I'm not sure - I don't use or know GWBasic. Back when I did BASIC (of the Sinclair BASIC and Locomotive BASIC flavours), variables were untyped values were typed, and the system would use integer arithmetic on integer values, but convert automatically to floating point when necessary using only half-understood (by me) rules. Many modern programming languages allow you to declare the type of the variable. In many BASICs, int(X) will coerce X to integer, IIRC. --Stephan Schulz (talk) 14:31, 17 January 2011 (UTC)

According to the GWBasic documentation, single-precision floating point values are only guaranteed accurate to six significant digits. If you use double-precision, you get 17 digits of accuracy. You can make a variable double-precision by using # in its name instead of !. (I found the documentation here.) Looie496 (talk) 17:54, 17 January 2011 (UTC)

If the original poster intends to work with numbers that have two decimal places, and wants to test numbers for equality, he should avoid all forms of floating-point arithmetic. As Stephan Schulz commented above, he should convert his numbers to integers and work with those. Testing floating point numbers for equality is a well-known tarpit. Converting decimal numbers to binary (internal to the computer) and back again messes up the comparison since simple decimal fractions may have no exact counterpart in binary. Roundoff due to the binary conversion will spoil any tests for equality. See our article on floating point for background. EdJohnston (talk) 18:06, 17 January 2011 (UTC)

If you must compare floating-point numbers, do not check for exact equality. Use the following trick: (A ≈ B) → (A-B)≈0 → (A-B)²≤ ε for small epsilon. Select a suitably small one for your purposes. In other words, replace IF A=B by IF ((A-B)*(A-B))<1E-6. Nimur (talk) 21:06, 17 January 2011 (UTC)

That's a good trick. (The purpose of the squaring is to ensure the result is positive, I gather.) 81.131.47.204 (talk) 22:18, 17 January 2011 (UTC)

I think it's more usual to use abs(A-B) < epsilon, so as to avoid a floating-point multiplication (though it's unlikely to make much difference unless you're doing huge numbers of comparisons). AndrewWTaylor (talk) 12:42, 18 January 2011 (UTC)

When using this trick, you should also be aware that it breaks transitivity. A ≈ B and B ≈ C does not imply that A ≈ C. I believe that there's no way to compare floating-point numbers for equality that doesn't cause unexpected behavior in some way. My brother once implemented an arbitrary-precision math library, which would calculate as many digits as it needed automatically. Testing for equality was not very useful, though, because if you tried to compare two numbers that were equal, it would diverge as it would keep calculating more digits forever, looking for a difference. Paul (Stansifer) 17:23, 18 January 2011 (UTC)

Thanks, I have changed to using pence instead of pounds, and now it works without any problems. I tried making the variables integers by putting % on the end, but that gave an overflow error. By the way, the Windows and Linux nearest equivalent to GWBasic seems to be SmallBasic. 92.28.241.29 (talk) 00:07, 19 January 2011 (UTC)

[SOLVED] Auto config messed up display

Hi all,

I have a HP w19 monitor (19") and yesterday, when I pressed the auto config button, the display shifted almost 4 inches to the right, leaving a black on on the side. I tried pressing the auto button again, but the screen remained shifted.

This is what I have attempted so far:

1. Adjusting the horizontal position using the built in monitor menu

2. Resetting the monitor to the factory settings

3. Adjusting the resolution to the lowest possible (640 x 400) and then back all the way up (1400 x 900)in Windows' display options

4. Adjusting the resolution in Nvidia Control Panel (I have a 8800 GTX, onboard is a 6150 LE)

5. Going into a game and adjusting the resolution from there

6. Unplugging the monitor and waiting for 15 seconds

7. Mashing the auto config button repeatedly with increasing frustration

8. Shouting at the monitor

Nothing has been fruitful thus far. The display seems to think that the center of the screen is 4 inches right of where it used to be and I can't convince it any differently.

If anybody has any ideas, please chip in. I'm tearing my hair out over here. 170.140.169.129 (talk) 19:45, 17 January 2011 (UTC)

(P.S. When I take a screenshot, it takes a picture of the normal display without the black bar, not what is currently being shown on the screen)

Download and install its drivers? [8] Louder shouting? Check the data cable is plugged in properly? 81.131.68.227 (talk) 20:29, 17 January 2011 (UTC)

Unfortunately, none of that worked. Is there any software that lets you control screen position? I've tried Display Tuner and it didn't work. —Preceding unsigned comment added by 170.140.169.129 (talk) 21:34, 17 January 2011 (UTC)

Fixed the problem by plugging the screen into my roommates's laptop and cycling through the display modes. 170.140.169.129 (talk) 00:04, 18 January 2011 (UTC)

Weird noise from hard-drive

Just a few moments ago, my computer made this weird whirring sound without explanation, and now it stopped. Nothing else has occurred. What the hell? 24.189.87.160 (talk) 21:17, 17 January 2011 (UTC)

When the ambient temperature is really cold, like now in the Northern Hemisphere, I've noticed my laptops make a weird murmur-like sound, like a fan that needed some oil. After they boot up (and warm up), it stops. Could this be what you're reporting? I haven't noticed any change in performance with my laptops, so if that's what it is, I wouldn't get too worried.--el Aprel (^facta-_facienda) 22:10, 17 January 2011 (UTC)

Is it possible that our questioner is referring to the case of a desktop or tower computer when mentioning the hard-drive in the heading? This is a common misunderstanding. If it is the case, the noise could simply have come from the fan in the power supply having a transient wobble. Can our questioner please clarify what he or she means by "hard drive"? HiLo48 (talk) 22:32, 17 January 2011 (UTC)

I meant the hard drive in my laptop (at least that's where the noise seemed to have come from), but thanks for the info about cold weather causing it. It is freezing where I live. 24.189.87.160 (talk) 22:51, 17 January 2011 (UTC)

It is probably thermal recalibration or something else harmless. You could look at the drive's S.M.A.R.T. parameters to see if it has noticed any danger signs. One freeware Windows program that will show SMART parameters is System Information for Windows. -- BenRG (talk) 01:30, 18 January 2011 (UTC)

The above comments notwithstanding, now would be a good time to ensure that you have a current backup, just in case. Mitch Ames (talk) 10:50, 18 January 2011 (UTC)

Professional Website for Under 500$?

So, here's the deal. I am working with a team and we need a website. None of us have much HTML experience however, only a little. We were wondering what the best way to get a website for under 500 dollars would be. Should I be looking at website designers, finding a website builder online (akin to Website Tonight but allows us to host on our servers), or should we just buy something like Dreamweaver and suffer through the learning curve. I might be missing something that could be found in an article on Wikipedia which is why I'm asking here.

We have servers, just no design skills.--128.54.224.231 (talk) 21:47, 17 January 2011 (UTC)

If your website is reasonably straightforward, you should learn HTML, and design your website yourselves, because it is very easy to learn. A functional website need not be complicated to design; and there is no shortage of web-based information, tutorials, and instructions. Numerous pre-fabricated web content "frameworks" exist if you need more complicated features, like an online shopping cart, a forum, or a "blog" style interface. Do you need help locating technical resources for learning basic web design, or artistic/design style guidelines, or some other resource? Nimur (talk) 23:38, 17 January 2011 (UTC)

KompoZer is regarded as the best free HTML editor. 92.28.254.64 (talk) 00:12, 18 January 2011 (UTC)

I can build you a web site for under $500. Just send an e-mail with exactly what you want on the web site. I usually make sites in Flash, but if you prefer pure HTML, I can do that, too.--Best Dog Ever (talk) 00:57, 18 January 2011 (UTC)

Or, if you'd rather not hire a designer, you can purchase a nice template from templatemonster.com for anywhere from $50 to $80. You can then open the template in an HTML editor of your choice and customize it. I think Microsoft Expression is an easy program to use for this purpose. If you'd rather make one from scratch yourself, look at using Adobe Fireworks or Adobe Photoshop, which can both export images as HTML slices, and allow you to draw things and then move them freely across the screen -- something that cannot be done with ease in other types of site editors.--Best Dog Ever (talk) 10:15, 18 January 2011 (UTC)

General web templates are the way to go if you're not planning to have your site custom made or simply don't have the time/skill/$$$ to do so.Smallman12q (talk) 00:04, 19 January 2011 (UTC)

capacitive touch or resistive touch.....?

Hi, I am planning to buy a touchscreen cell phone. and I am really confused that i should go for a capacitive touch or a resistvie touch.. Please tell me which one is durable ... I know that capacitive is more responsive than a resistive touch and it feels good to operate a capacitive touch than a resistive. But I want to know which one have longer life capacitive or resistive as I know resistive is cheaper than capacitive.

I have selected two cell phones to buy both have same price but one with capacitive touch has 2MP camera and not having a goood look and other with resistive has 3.5MP camera with a stylish look.......please suggest me for which one I should go.. —Preceding unsigned comment added by 220.225.96.217 (talk) 22:44, 17 January 2011 (UTC)

A capacitative touchscreen typically has a front made of glass or hard plastic and a screen protector can be placed over the top for additional protection. A resistive touchscreen has a soft surface that is physically depressed and so can't be protected in the same way. So a capacitative screen is less prone to accidental damage. --Colapeninsula (talk) 10:23, 18 January 2011 (UTC)

Is android worth it?

I wonder..... does android OS worth it the response it is getting and the people who are mad for it....? —Preceding unsigned comment added by 220.225.96.217 (talk) 23:46, 17 January 2011 (UTC)

Yes, it is very much worth it IMO. You can read online reviews of Android phones and find out for yourself. 24.189.87.160 (talk) 00:05, 18 January 2011 (UTC)

And IMO, iOS is better and I'd prefer that. But then that's the thing about opinions, you'll have to make up your own. Dismas|^(talk) 02:19, 18 January 2011 (UTC)

Worth it compared to what? iOS? I'd say certainly if you want to be able to modify/control it more easily. There are better OSes, but they have much lower market penetration at the moment (MeeGo & others), which means fewer devices and less momentum. ¦ Reisio (talk) 02:29, 18 January 2011 (UTC)

Can iTunes application on Windows play purchased movies?

If I buy a movie on my iPhone and back it up to my Windows XP computer using the iTunes application that knows about my account, will I be able to watch the movie on my PC? Peter Michner (talk) 23:53, 17 January 2011 (UTC)

Yes. I've watched movies I bought on iTunes and proceeded to watch it on my computer. — Preceding unsigned comment added by General Rommel (talk • contribs) 01:37, 18 January 2011 (UTC)

January 18

Mac folders icons?

I've had my Macbook for years now, but something still bugs me. In Windows, it's really easy to change the icon for a folder, but on my Mac, I can't seem to find out how to do this. When I dock a folder, there's an option to display the folder as a "stack", which turns the icon into the first image in the folder; but when the folder in question is not on the dock, there's no such option. Is it possible? Thanks! 69.207.132.170 (talk) 02:14, 18 January 2011 (UTC)

It's easy on a Mac, too, when you know how. Let's say you have a photo in file XYZ.jpg that you really like and would like to be the icon for a folder. First, copy the photo to the clipboard. Then: 1. Select the folder in question. 2. Go to File > Get Info (Apple+I). 3. Select the icon of the folder — actually click on the little icon of the folder at the top of the Get Info window. Now, go to Edit > Paste (Apple+V). Presto, chango! The icon is now set to the photo. (You can copy and paste icons from other files that way, too — select the icon in Get Info, then go to Copy). If you want to undo it and go back to the default, just select the icon in Get Info, and click Delete. --Mr.98 (talk) 04:41, 18 January 2011 (UTC)

Filters for Ted Notepad

Please could someone explain what the filers here http://jsimlo.sk/notepad/filters.php for the Ted notepad do and how they are used? I have read the filter part of the manual here http://jsimlo.sk/notepad/manual/ , but I still do not understand. Thanks 92.28.254.64 (talk) 03:23, 18 January 2011 (UTC)

Mac Program most similar to coffeecup?

What Mac program is most similar to coffee cup?--128.54.22.172 (talk) 04:05, 18 January 2011 (UTC)

If you want to be able to access remote file-systems, and especially if you want to edit files as if they are local-files, I would recommend MacFUSE, an implementation of Filesystem in Userspace and sshfs. If you only want an HTML WYSIWYG editor, there are numerous options. Consider reading through our comparison of HTML editors, sorted by operating-system. Nimur (talk) 04:13, 18 January 2011 (UTC)

External monitor on a netbook

While I'm sure this question has been asked, I couldn't find the answer in the archives. I have an Acer Aspire with at 10 inch screen (running XP). I picked up a 17 inch LCD monitor. While I can get both monitors working, I can't get the settings to stick. When I click "apply," everything goes back to the small monitor. When I move all of my icons over to the larger monitor and click refresh, everything reverts back to the Aspire screen. Even the bar at the bottom of the Aspire screen stays there. Any suggestions? 99.250.117.26 (talk) 04:09, 18 January 2011 (UTC)

Unicode assistance

Alright, so I have a PHP program that I run that I use to assist myself with deleting images marked with {{NowCommons}}, as well as a bot that does the same. However, I'm running into issues with Unicode. This is a field that has continued to baffle me; I learned about it in IT classes in college, but I don't know much about its implementation. So I'm having two issues, which are really just one issue:

1. I cannot, for the life of me, figure out how the browser interprets certain characters as unicode and others as non-unicode. For example, I printed out the 8-bit characters as they came to me via stream on the Wikipedia API I use. Here is how part of the original upload log on Commons:File:MapSagaMiyaki.png appears on Commons and on my php page respectively:

   {{市町村地図画像情報(Lincun) |都道府県=佐賀県 |都道府県Latin=Saga-ken...

   {{å¸‚ç”ºæ‘åœ°å›³ç”»åƒæƒ…å ±(Lincun) |都道府県=佐賀県 |都道府県Latin=Saga-ken...

   Now obviously the second one is incorrect, but how does my browser tell the difference? If I stream it on my API, they look the same to me (I think). I want to output the text so that it's not so ugly to me. My solution thus far has been something like what I've done below.

2. I'm using a rather ugly piece of code at the moment to test for 16-bit characters; I'm not sure if it will always work; perhaps it will even throw false positives at me. It mostly goes like this:

   $chr = $str[$j];

   $nxtchr = $str[$j+1];

   $unicode = preg_match("/^[\p{L}\p{M}\p{Z}\p{S}\p{N}\p{P}\p{C}]$/u", $chr.$nxtchr);

   Is this a bad implementation? Because it seems like guess work at this point. Magog the Ogre (talk) 09:52, 18 January 2011 (UTC)

Hi, Not sure if I understood the problem completely. Maybe it's got something to do with the encoding of your page. Maybe something like this: <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/> will help. 210.50.249.143 (talk) 10:32, 18 January 2011 (UTC)

That did it, I'm baffled. So now let me rephrase: How did I type the Japanese code above, and have Wikipedia and our browsers distinguish between the unicode Japanese and my gibberish which is the utf-8 equivalent? And how can I get a PHP string to recognize that? Magog the Ogre (talk) 14:00, 18 January 2011 (UTC)

Hope this page would be helpful. Oda Mari (talk) 16:03, 18 January 2011 (UTC)

Forget about Unicode. There are various incompatible ways of representing characters as bytes or sequences of bytes, such as Windows-1252, Shift-JIS, and UTF-8. If some program guesses incorrectly which encoding is being used, or is explicitly told to use the wrong encoding, then you will get gibberish. The <meta ... line suggested by 210.* instructs the recipient to use UTF-8, which was the actual byte encoding you were sending in this case (whether or not the recipient knew it). Wikipedia always uses UTF-8, and correctly identifies it as such. If your software is Wikipedia-specific, you can probably just use UTF-8 everywhere and forget about everything else. -- BenRG (talk) 22:02, 18 January 2011 (UTC)

Counteract jpg compression artifacts

What's under my control: I'm creating a simple image with only two or three different colors (the image is actually just a snip of text). I am then uploading this image to a website. What's not under my control: The website then manipulates the image and creates a (more) compressed image of the original (jpg format). The resulting image has the artifacts you would expect (fuzzy edges on the letters, uneven color). My Question: Is there a way to create the original image in a way that will result in a smooth image after the compression? I want it to look more like a gif. —Preceding unsigned comment added by 210.50.249.143 (talk) 10:21, 18 January 2011 (UTC)

FWIW, PNG format is lossless. Magog the Ogre (talk) 10:29, 18 January 2011 (UTC)

Thanks. But the jpg compression is mandated by the service I'm using. My question is: can I make an image that will look nice AFTER compression.

What happens now: [Original] -jpg compression-> [fuzzy Original]

What I want to do is: [modified Original] -jpg compression-> [looks almost like Original] 210.50.249.143 (talk) 10:34, 18 January 2011 (UTC)

In my experience red and green colors tend to suffer from this the most, whereas black is hardly noticeable. You say the website compresses the jpg you upload, which means it actually gets compressed twice. Is there a jpg quality control on the program you use? Setting this to 100% should reduce the amount of compression taking place on your end, so that when you upload the image and the site re-compresses it, it's only compressed once from a high quality original. And you mentioned gifs; converting the jpg to 256 colors with dithering will emulate the effect of a gif and perhaps will help it survive the sites compression better. But all this is mostly just ideas from my own experience, not facts. Without knowing the site and the programs you use I can't offer any more —Preceding unsigned comment added by 82.44.55.25 (talk) 10:46, 18 January 2011 (UTC)

thanks. I've tried your suggestions, but didn't get any better results. The website I'm talking about is gumtree. I want to upload a picture that stands out as a thumbnail. Black and white doesn't quite cut it for that. 210.50.249.143 (talk) 11:18, 18 January 2011 (UTC)

Probably, there's no way to do it, then. It sounds like they produce jpegs with fixed, not-high, quality settings, and that's always bad for non-photographic images. Paul (Stansifer) 17:12, 18 January 2011 (UTC)

Sorry if this information is too technical; but JPEG compression is very mathematically intense and requires a bit of "unintuitive" image-processing. It is possible to design a source image that is not garbled badly, even under a high-compression (low-quality) lossy JPEG encoding. But you must design an image with certain properties - not any image can compress gracefully. You can switch to an image, or modify your existing image, so that it only contains low frequencies. (For example, you can apply a blur-filter, or just pick a different image that is already more "smooth"). That should eliminate "jaggies" (actually, they're a different form of artifact related to Gibbs effect ringing). You can also switch your image-processing program to work in YUV color-space, or (YCbCr), noting that U and V components get much more heavily compressed than Y; so select (or design) colorful images that have low dynamic-range and (most importantly) a low-variance in the U and V channels. Through iterative trial-and-error design, you can determine which of your image creations have the most graceful output when highly compressed. I know these "instructions" are not very helpful to most artistic image-designers (these instructions are barely even helpful to skilled numerically-trained image analysts); in practice, a more useful "instruction" would be "do not use highly-compressed JPG" - but that seems like it's not an option for the OP. Nimur (talk) 20:35, 18 January 2011 (UTC)

It occurs to me that straight horizontal or vertical transitions along the edge of JPEG chunks should be fine. They will probably occur every 16 pixels in the output image. In a quick informal test, it looks like there may be a lot of positions where a perfectly horizontal or vertical line could live without creating a mess. But I think that any other angle will create noise. Paul (Stansifer) 00:18, 19 January 2011 (UTC)

Right. That is a special case of concentrating the energy of the 2D discrete-cosine-transform of each macroblock of your image into the first elements of the spectrum that is ordered by this zig-zag pattern, described in this section of our article. You want to compose your image so that its Y, U, and V channels are primarily a weighted superposition of the basis functions illustrated in this image with most of the coefficients exactly zero. If you can accomplish this, by keeping the rest of the non-zero coefficient values above those thresholds specified in the standard quantization table (or whatever non-standard QT is used by the JPEG codec implemented on the server) (and also, having zero-bit values when shifted by the QT thresholds), you will produce an input image that compresses exactly losslessly using the JPEG algorithm. Paul Stansifer's suggestion accomplishes a special case of this technique, by using only DC elements (the first-element of the spectrum) (and also assuming a non-pathological quantization table). The number of (parenthetical caveats) that I've had to add has become comically large here. I really don't think these instructions are practical, but maybe somebody will find them interesting). Nimur (talk) 01:08, 19 January 2011 (UTC)

Resetting Default Search Engine in Firefox 3

Resolved

I very often use the address bar when searching for stuff (as opposed to the little search box on the top right). Recently, after installing AVG, my default engine got changed to Yahoo. While I can tolerate Yahoo to a certain extent, after installing something else even more recently it got changed to Bing. Is there anything I can do to change it back to Google - I have some search engine plugins for Google which I got for a reason. Thanks. --KägeTorä - (影虎) (TALK) 14:50, 18 January 2011 (UTC)

Click on the little down arrow next to the search bar and select "Manage search engines". Then make sure Google is at the top of the list.--Shantavira|^{feed me} 15:11, 18 January 2011 (UTC)

Thanks - but I am talking about searching from the address bar. --KägeTorä - (影虎) (TALK) 15:14, 18 January 2011 (UTC)

Try these instructions. 88.112.59.31 (talk) 16:23, 18 January 2011 (UTC)

Excellent! That worked, thanks! --KägeTorä - (影虎) (TALK) 16:41, 18 January 2011 (UTC)

Slim "Information Organizer" for Windows

My friend uses this really awesome program called "NotePad" by a company called Ibrium on his Mac. Its a simple turbocharged version of wordpad and it lets you jot down and organize information and notes really easily. I do alot of research and this kind of thing would be really useful. Does anyone have any idea of a similar, slim, efficient program for Windows? --Cacofonie (talk) 19:32, 18 January 2011 (UTC)

I'm not sure about slim/efficient, though there is Microsoft OneNote. The old interface reminds me of early versions of Lotus Notes. There is a relevant category at Category:Notetaking software.Smallman12q (talk) 00:01, 19 January 2011 (UTC)

My antivirus (Avast!) blocks the NotePad link webpage above as being or having a trojan horse. 92.28.241.29 (talk) 00:17, 19 January 2011 (UTC)

Firefox's internal default start page

Resolved

When Firefox is updated (and, I think, when non-distribution-modified versions are first started), it displays a mozilla.org page specific to the version. That page says things like "This is the latest version" or "This is old, you should update (again)". Unfortunately, I don't have a copy that needs updating at the moment; where are those pages? --Tardis (talk) 19:45, 18 January 2011 (UTC)

Help/Release Notes (which gives me this page) may be what you're after. AndrewWTaylor (talk) 20:07, 18 January 2011 (UTC)

Thanks; I saw that too. But the next answer was the target (I wanted to see the welcome page rather than read about the release). --Tardis (talk) 01:03, 19 January 2011 (UTC)

http://www.mozilla.com/en-US/firefox/3.6.12/whatsnew/ 82.44.55.25 (talk) 20:39, 18 January 2011 (UTC)

That's precisely it. Thanks! --Tardis (talk) 01:03, 19 January 2011 (UTC)

Extra Windows 7 Installation

I've recently replaced my motherboard and went to reinstall Windows 7 and things went very smoothly during the installation. The problem is, it seemed to have ignored what I wanted without letting on that it was ignoring me and rearranged my drive letters, and it there also seems to be another installation of windows on the computer. When I boot up now, it asks me which OS I want to load, Windows 7 or Windows 7(the previous installation).

Does anybody know a method of finding out which is the active installation and how to remove the previous one? I'm not so worried about the drive letters, it's more a curiosity than anything else.

Thanks 142.244.35.91 (talk) 21:54, 18 January 2011 (UTC)

Just try and see if it is the first or second one. To change the settings, type System Configuration into your start menu, then choose boot. F (talk) 00:01, 19 January 2011 (UTC)

Where i can find tutorials for Bing App Development?

I just download the Bing API 2.0 SDK yesterday but i can't find any tutorials or videos on how to develop with it, does anyone know where i can find them?