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Wikipedia:Reference desk/Archives/Computing/2009 November 21

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November 21

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Media player can play .iso images directly?

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I've transferred some old VHS tapes to DVD. I'm then backing up these DVD to .ISO files onto a hard drive. Are there any Mac video players or HD media boxes that can play back .iso images directly? (without mounting) --68.103.143.23 (talk) 03:20, 21 November 2009 (UTC)[reply]

There certainly is, VLC Media Player can play back ISOs of DVDs (seriously, is there nothing that video player can't do? it's like magic!) Belisarius (talk) 12:09, 21 November 2009 (UTC)[reply]
Well, mine seems to not understand when I've downloaded new codecs or filters despite WMP being able to figure it out. It also has some very bizarre behaviour when there's an existing window and you try to start up a new file from WE. Don't get me wrong, I have it and I like it, but it sure ain't no magic program! Matt Deres (talk) 14:14, 22 November 2009 (UTC)[reply]
...not to mention its well-known propensity for crashing. --Mr.98 (talk) 17:15, 23 November 2009 (UTC)[reply]

Windows Mobile software compatibility issues

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I just bought a dirt cheap 2nd-hand HP iPAQ 6365 smartphone running Windows Mobile 2003 SE (TI OMAP1510). It is very frustrate for me to see many software already are incompatible with this old model. I downloaded many software and noticed that my PDA fails to run the installer. Is there a way to check the compatibility of downloaded Pocket PC software so I don't need to waste my time trying?

By the way, I tried to install Skype on this underpowered model. It seems like there once was a version specially built for the 6365. However, I could not locate it on Skype's official site. Never mind, I tried to download software updates from HP and their ftp site seems to drop support for this model. -- Toytoy (talk) 09:58, 21 November 2009 (UTC)[reply]

In additional to Skype problems, I find Windows Media Player on the PDA sucks. The interface takes most of the space. When you play a movie full screen, if you click the touch screen by accident, it returns to the interface mode and rotates the movie 90 degrees back. It is nearly impossible to watch any educational video using it. You cannot go back a little bit when you don't fully understand. -- Toytoy (talk) 12:30, 21 November 2009 (UTC)[reply]

Best way to calculate an ETA...

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I'm making a program where something needs to be processed for a while and it gives a little timer estimating how long it will be until it's finished. You know, like how when you're downloading something from the internet it says "5 minutes, 24 seconds remaining", and it bases that on the how fast your download speed is. I'm wondering what the best way to make an estimation like that is. Are there any guidelines?

The first thing I did (just because I was lazy) was to simply take how much time had passed since the last update, divided that with how much data I had processed and multiplied it by how much data was left. Obviously, this is not a very good method, since it is vulnerable to small temporary changes in speed and the number was all over the place. What I have now is a simple moving average of the speed from the last 60 updates (since it updates about twice a second, that would be about the average of the last 30 seconds). Is there a better way? Belisarius (talk) 12:03, 21 November 2009 (UTC)[reply]

That system is still vulnerable to wild variations right at the beginning if the processing speed changes. A few suggestions:
1) Don't give an estimate until several steps have passed. This can be annoying, though, if they start it going and want a time estimate right away.
2) Store the historic average speed and use that initially. This can result in a jump (either up or down) when you switch from that to the current average. To minimize that jump, you might want to slowly change the weighting on the weighted average between the historic speed and current speed. You could start out at 100% the historic speed, then go to 90% historic and 10% current after the first step, etc. The simplest way to store the "historic average" is just to overwrite it with the average time for the last run, after it completes. A more complex way is to do a recency weighted average of the last few runs.
3) List steps completed instead. So, rather than give a time estimate, say something like "10:38 elapsed, and 19 of 38 steps completed". This completely eliminates the problem of time estimates jumping all over the place, as there aren't any. The user can come up with one based on the info provided, if he wants, but can't blame the program for giving bad estimates. This method has the advantage of being the simplest to code and provides valuable debugging info: "why does it always stall on step 19 ?". (It's also quicker for the user to detect when a stall occurs, as the steps stop going up, rather than just having an increasing time estimate, or, worse yet, a time estimate that never changes.) Note that ideally each step should be of equal length, but they don't necessarily have to be. You can also weight the steps: "This step takes about ten times as long as each of the others, so I'll count it as ten steps".
The third option is my personal favorite, and I always use that. StuRat (talk) 12:34, 21 November 2009 (UTC)[reply]
Another scheme that seems to be used a lot is show second-by-second updates knocking 1% off until you get to 40%, then do a final update at completion. The progress bar trundles along to around 40%, pauses for some time, then jumps to 100%. In my experience that is how it works in Windows Update :-) Astronaut (talk) 15:41, 22 November 2009 (UTC)[reply]
I have found this blog post useful in thinking about the psychological effects of different updating systems, if you care about that. Most users just want to see that some progress is happening from the very beginning, and care more about that than accurate estimates. They care about apparent smoothness of process, and like things that speed up towards the end. They do NOT like waiting 10 seconds for an estimate. All of this is independent of how much time it actually takes. --Mr.98 (talk) 17:12, 23 November 2009 (UTC)[reply]

:-h emoticon

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Can anyone explain what this emoticon means: ":-h" ? There is no information in the article for it. thanks --helohe (talk) 13:16, 21 November 2009 (UTC)[reply]

"lmao 10x ur so funny".
I don't know if this is a reputable source, but one site says it means "wave hello/goodbye"[1]. It doesn't seem very common though, and may have other meanings. —Preceding unsigned comment added by 193.172.19.20 (talk) 17:27, 23 November 2009 (UTC)[reply]
agree with 19.20. Specifically as used on Yahoo Messenger smileys PrinzPH (talk) 17:23, 25 November 2009 (UTC)[reply]

Google email

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Is there a email address of Google, so that it can be reached through email?--Mikespedia (talk) 13:54, 21 November 2009 (UTC)[reply]

Google is a huge company, of course, so there's no single email address for the whole company. They have their ["Contact Us" page that has a variety of ways of getting in touch with them depending on who you want to contact, and why. APL (talk) 21:02, 21 November 2009 (UTC)[reply]

Dump password hashes on Mac

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Is there a way to dump the password hashes under Mac OS X? Preferably in a way that results in a unix-style passwd file. Horselover Frost (talk) 16:37, 21 November 2009 (UTC)[reply]

Some googling turns up this little page which shows you how to do it (up to Tiger). They are apparently shadowed and stored in /var/db/shadow/hash/ and can easily be dumped. (and btw, awesome nick) Belisarius (talk) 00:01, 22 November 2009 (UTC)[reply]

Java Scanner

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Is there a way to use the Scanner function in Java which means when a user is inputting some text under the scanner on the command line, the text isnt shown. I am thinking of something like in unix when typing in a password, nothing is shown on the screen to show the user is typing someting in. Is this possible in Java? —Preceding unsigned comment added by 86.133.56.241 (talk) 20:56, 21 November 2009 (UTC)[reply]

No, you can't do that with Scanner, and it's very difficult to do it at all in Java. The functionality is not in the standard library , so if you really want to use it, you would have to use a custom JNI solution that uses the C function getpass(). So either you have to install some 3rd party library that implements it or make it yourself (and either way will kill portability). I strongly suggest you just ignore that little UNIX-convention. If you are worried that you are being a terrible programmer and making horribly unsafe and dangerous software, don't worry, Bruce Schneier's got your back (well, not completely, but he does say it's not a cardinal sin to have unmasked passwords). Feel free to ask the user to enter it in cleartext. Or, you know, switch programming languages. It's trivial to do in Python Belisarius (talk) 23:55, 21 November 2009 (UTC)[reply]
Not scanner but the Java tutorial has [2] about password fields Dmcq (talk) 00:20, 22 November 2009 (UTC)[reply]
Java 6's Console class gives you more control over the behavior of the terminal, including a readPassword() method that is specially designed for reading passwords. --Spoon! (talk) 09:34, 22 November 2009 (UTC)[reply]

producing DVD's that will play on television

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I am trying to produce DVD's with my pictures that will play on my TV. I have Windows Vista. I have tried DVD-RW, DVE+RW and DVD-R, and when I try to play them my DVD player says "bad disc". What must I do to correct this? —Preceding unsigned comment added by 216.223.225.133 (talk) 21:01, 21 November 2009 (UTC)[reply]

For best compatibility, use a DVD-R disc, and make a video DVD of it. It is (of course) not enough simply to burn a set of video files to it (indeed, which format should you use? AVI, MPEG, WMV, MOV, QT, ... ?), but you need to use an application that really creates a standard video DVD. Windows Media Player, Windows Media Center, and Windows DVD Recorder can be used. --Andreas Rejbrand (talk) 21:18, 21 November 2009 (UTC)[reply]
But now it seems like you do not have video files, but only pictures. Then the app also needs to create a video from these pictures. I am not sure, but perhaps e.g. Windows DVD Recorder can do this. Otherwise, you can always use Windows (Live) Movie Maker. --Andreas Rejbrand (talk) 21:20, 21 November 2009 (UTC)[reply]
Note that if you want to use DL discs, DVD+R DL booktyped to DVD-ROM DL is better then DVD-R DL [3]. BTW if you have a DVD player with JPEG support bear in mind these players often are limited in what they support but provided limited info on what is supported. You should at least check out your user manual and see what it says. And when burning I recommend you make sure you include ISO level 1 file system. I've also heard that sometimes they don't work with DVDs but only CDs. Nil Einne (talk) 21:25, 21 November 2009 (UTC)[reply]
Window Movie Maker can make a movie from still images and adjust the time each image is on screen (I did just such a thing to help my neice make a short plasticine animation). You might also be able to add audio, though I haven't tried this.
I haven't tried putting the result onto a DVD, the the answers above seem reasonable. Astronaut (talk) 15:36, 22 November 2009 (UTC)[reply]
The trouble is that it depends on the DVD player. My Magnavox player will play all combinations of DVD +,-,R,RW plus VCD and it's cousins. However, my son's Sony player refuses to play RW's and +R's although it'll happily play -R's. So you really need to check the player you're intending to use. SteveBaker (talk) 01:01, 22 November 2009 (UTC)[reply]

How to extract from .tar files on Vista 64-bit

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Resolved

Hello! I need to extract from .tar files on my Windows Vista 64-bit laptop, but when I download tar from the GNU project website and try to run it, I get an error message that says it is incompatible with my 64-bit environment. Is there any alternative for those of us with 64-bit systems? Almost all of the GNU software requires tar to extract it.--el Aprel (facta-facienda) 23:04, 21 November 2009 (UTC)[reply]

Tugzip and 7zip should both extract tars. -- Finlay McWalterTalk 23:14, 21 November 2009 (UTC)[reply]
Thank you!--el Aprel (facta-facienda) 23:44, 21 November 2009 (UTC)[reply]

cracking fable

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hey, so my friend gave me this disk with a fable crack, i installed alright but then i get to a point where it says something like "cannot find library", i have no idea what this means and my friend can't remember. i'm not sure if its just individual to the game or if it happens with all cracked games, but in anycase i need help.

anyone out there who can? —Preceding unsigned comment added by Masheeofthefunk (talkcontribs) 23:38, 21 November 2009 (UTC)[reply]

Please don't ask us questions about pirate software; we're not interested in helping you steal. 87.115.143.163 (talk) 23:39, 21 November 2009 (UTC)[reply]
That's correct, this isn't a place to ask such questions. Comet Tuttle (talk) 03:27, 22 November 2009 (UTC)[reply]
I'm not sure that there's a policy against it. Regardless, it's not really answerable. All of these cracks are different, made by different people. There's no way we could diagnose the problem without being familiar with that particular crack. Since essentially no tech support is offered for those cracks if you can't make it work on your own, you're pretty much out of luck. APL (talk) 05:42, 22 November 2009 (UTC)[reply]
Technically if we're talking about a game crack there may be instances where no piracy is involved, e.g. if the OP simply doesn't want to have to take the DVD/CD around with them. However the OP's question suggestions this is unlikely and in any case I don't think anyone will find much help here. To be blunt, I've always wanted to say this when these sort of questions come up (especially the P2P ones) and this seems a good opportunity, regardless of the motives of the person involved, if they thinks it's a good idea to ask here, I wouldn't recommend they do anything of the sort since it seems unlikely they have sufficient knowledge or common sense to avoid doing anything stupid like getting malware. (There are places where you may be able to get some help from users and you can of course try to find any other reports of similar problems but again, anyone who needs to be told that shouldn't be trying such stuff.) Nil Einne (talk) 10:33, 22 November 2009 (UTC)[reply]
I find it helps the pirates to know someone who is personally effected by this. I write computer games for a living (I do the pretty graphics bits using lots of ikky math and tons of clever software). I earn a bonus as a part of my income that directly relates to the number of sales of games that I worked on (that's a common thing in the industry). So when you pirate a game that I worked on - you are a thief. You are quite literally stealing money from me and all of my friends at work - just as surely as if you'd picked my pocket or burglarized my home. Don't expect me to feel charitably towards that kind of behavior. What's worse is that the better I do at my job - the harder I work to make games that you'll like - the greater the chance that you'll steal it. Gee - thanks! But worse (far worse) is that the amount of money piracy costs is enough to cause publishers (not developers like me) to start instituting crazy - and frankly, bloody annoying - copy protection and DRM schemes that upset everyone. If piracy went away tomorrow and publishers could trust people to do the right thing - then the world would be a vastly better and simpler place. SteveBaker (talk) 17:58, 22 November 2009 (UTC)[reply]
Have software (games) companies worked out what would happen if they were to make games a third of the current price? Would they get three times more the sales? This would be one way to reduce piracy a great deal... makes games far cheaper. I think the prices of some games are exorbitant and out of the range of younger/poorer people. Sandman30s (talk) 13:53, 23 November 2009 (UTC)[reply]
Can't do it. In my experience, and in round numbers, it takes about 100 engineers earning between 30 and 50 bucks an hour three solid years to write a AAA title - that's twenty million dollars in salary alone - plus the cost of computers, software, building rental, electricity, outsourced art, music licensing, voice actors, MoCap studio fees, QA department, HR, IT, etc. Then you have middleware licensing fees, the publishers, console manufacturers and the high-street stores take a gigantic slice and advertising another huge chunk. Only one game in 35 turns a profit - so the risks are spectacular. Even at $60 a copy - you've gotta sell a couple of million games at full price to break even - but because most games make a loss, the ones that do make it wind up paying for all of the flops. A large fraction of games are rented (not much profit there) and second hand sales dramatically eat into income. After not many weeks in the top 100 slot, the price of the game drops spectacularly - and then it's all over. I don't see where this "third of current price" thing can come from - there is really no chance to triple the size of the market overnight. But in any case, your theory that cutting prices cuts piracy doesn't work. iPhone games cost peanuts - yet the piracy rates on iPhone games are about the same as premium $40+ games. SteveBaker (talk) 04:29, 24 November 2009 (UTC)[reply]
You make some good points there and I really don't know what the solution is. You can't compare to the movie industry, because despite there being piracy of DVDs, people can pay $2-$10 to watch a movie in a theatre. This box office take accounts for a great deal of the initial profit for blockbusters, and if really good they continue to make money for years thereafter. Now with games, one can rent it from your video store for a week, but that doesn't help your case much. If games were a third of their price, I would have a much larger personal collection rather than relying on rental and swap clubs. Now I wonder how many people are in the same boat? I would love to see an experiment where someone takes the plunge and drastically reduces the price of an AAA title like you call it. Also, I didn't know that 1/35 games make a profit - surprising considering all the hype surrounding the huge profits made by COD4 MW2 and other titles this year. Sandman30s (talk) 07:19, 25 November 2009 (UTC)[reply]
Yeah - that's the thing though. When a game does well, it does SPECTACULARLY well. The programmers who worked on GTA IV (for example) got $100,000+ bonusses - people can get very rich when a game does make it. I don't doubt that the authors of COD4 MW2 are also very happy people right now. But those are in the tiny, tiny minority. You can count the number of those blockbusters that happen each year on the fingers of one hand...yet hundreds of games are made each year. That tiny minority is what keeps the industry going - but it's far from the norm. Generally, you consider yourself to be doing well if you turn a profit at all...and when you do, that profit has to pay for all of the previous flops and all of the flops that are yet to come! If not - then your studio goes out of business. Many games (such as the last one I worked on at Midway: "Career Criminal") are cancelled without ever seeing the light of day. In our case, that happened after a year of initial investigation with Tony Scott as a consultant and maybe 30 people - and a second year of full-on development with upwards of 100 staff. (screenshots) Career Criminal was running on PC, Xbox360 and PS3 (I had two PC's, two Xboxes and two PS3's on my desk while debugging graphics for dense crowd scenes and vehicle damage) - the graphics looked great - it ran without crashing - we had one major bank heist-with-a-twist mission fully working and a couple of others under development when it was basically realized that the thing was missing a "fun" factor - that's a tough problem to crack. How do you engineer "fun"? But with Midway's other woes, spending another half million dollars a month to pursue the idea was simply not tenable - so the project was flushed - and maybe 10 million dollars went down the drain with it. SteveBaker (talk) 06:28, 27 November 2009 (UTC)[reply]
Do you have a source for the iPhone stat? Not that I misstrust you. I'd just be interested in reading that. APL (talk) 21:18, 24 November 2009 (UTC)[reply]
[4] says that "Just over 60% of paid apps using Pinch have been pirated."...and goes on to explain that this is a low estimate. SteveBaker (talk) 06:28, 27 November 2009 (UTC)[reply]
Generally, I agree with you, but can I play Devil's Advocate for a second? In this case we're probably talking about a five year old game that you can buy used for $6. If the OP's choice wasn't to (a) buy new or (b) pirate, but (a) buy used or (b) pirate, what's the difference? The developer doesn't get royalties either way, do they? But just to clarify, I also think the OP would be better off just buying the game. Indeterminate (talk) 07:08, 23 November 2009 (UTC)[reply]
Minor nitpick, Fable: The Lost Chapters which was the PC version was released in September 2005 so really only just over 4 years Nil Einne (talk) 02:19, 26 November 2009 (UTC)[reply]
Well, there is a difference. If the used market is depressed because of piracy then people who buy a lot of new games are less able to sell their old games - and therefore have less disposable income to buy new games. So piracy does have an impact - even in the case of older games. SteveBaker (talk) 04:29, 24 November 2009 (UTC)[reply]