Wikipedia:Reference desk/Archives/Computing/2009 June 26

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June 26[edit]

MPEG-4 encoder?[edit]

Does anyone know of any free/open-source MPEG-4 encoders (as in the codec itself, not a conversion program)? I use video editing software from a couple years ago, before MPEG-4 was widespread, and it doesn't include any MPEG-4 codecs.

Thanks.

MPEG-4 isn't a single object, it's a collection of parts (see the article you linked to). My personal favourite for video encoding (MPEG-4 Part 2) is Xvid which is also quite a popular one, but there others in listed in the article. ZX81 talk 00:28, 26 June 2009 (UTC)[reply]
Sorry, I should have specified which part I meant (I was thinking part 2, as I doubt there's a free part 10 codec in existence). I wasn't previously aware that Xvid is open-source, so I'll have to try it out.
You doubt x264 exists? 69.245.227.37 (talk) 02:31, 27 June 2009 (UTC)[reply]
Not any more! Thanks for the tips, everyone - it's good to have free solutions for encoding both MPEG-4 part 2 and part 10.
Resolved

Windows 7 Upgrade Option[edit]

[1]

Why is Microsoft avoiding the words "free" and/or "discount" on their Win7 Upgrade Option web page? --hello, i'm a member | talk to me! 00:34, 26 June 2009 (UTC)[reply]

You are astute. If it does not say 'free' or 'discount' then the upgrade is probably not free or discounted. When Vista came out, there was a short time period before the debut when if you purchased a PC with XP, there was a coupon for a free Vista upgrade. Assuming Microsoft is going to run a similar promotion again this time, we evidently are not within that short time period yet. Tempshill (talk) 05:23, 26 June 2009 (UTC)[reply]
I just got next week's Best Buy circular, and they are offering a "discount" (next week only) on Windows 7 Home Premium upgrade pre-order, for only $50. These may be related. Mxvxnyxvxn (talk) 13:51, 26 June 2009 (UTC)[reply]
It looks like the free upgrade period began today, at least at Dell and Lenovo (the only two OEMs I checked). -- BenRG (talk) 14:44, 26 June 2009 (UTC)[reply]

Diagonal lines/snow across display when running Windows 7 on iMac[edit]

I recently installed WIndows 7 on my Mac (20" iMac with 2.4GHz C2D "Penryn" processor and ATI Radeon HD 2400 XT video card) via Boot Camp, and I've noticed that the display has faint snow/diagonal lines running across it when booted into Windows 7. The display is fine when I'm running Leopard, so I'm guessing it must be a driver issue of some sort. Does anyone have any idea how to fix this? I tried updating the drivers through Windows Update and it didn't help. (I also tried downloading the drivers from ATI's website, but the setup utility just doesn't seem to install the drivers). --CalusReyma (talk) 04:02, 26 June 2009 (UTC)[reply]

How are Push notification more battery saving?[edit]

How are Push notification more battery saving than regular polling? Specifically I'm talking about the iPhone. Isn't the phone constantly waiting to get a 'push'? How does this save power instead of regular polling? --69.148.26.115 (talk) 05:00, 26 June 2009 (UTC)[reply]

Sending a radio signal so that the cell base station hears it takes much more power than having a radio receiver open, waiting for an incoming signal. A radio signal weakens according to the inverse-square law to distance between phone and base tower, so quite a bit of energy is needed so that the base tower antenna gets enough of it. A radio receiver needs much less power, especially as the cell tower doesn't operate on tiny batteries and can send a much more powerful signal than the phone can.
This is also why a cell phone battery lasts days in standby, waiting for incoming calls, but only has a couple of hours of talk time, when it needs to send the speech signal. 62.78.198.48 (talk) 06:59, 26 June 2009 (UTC)[reply]

Extract each nth word of a string or text[edit]

Is there a website that easily lets you extract each nth word of a string of text to help crack codes? (Any places that allow you to try all potential orders for the discovered words would also be appreciated) - 131.211.210.114 (talk) 08:45, 26 June 2009 (UTC)[reply]

I don't know about websites, but this Perl command will print all permutations of every 7th word in f.txt:
perl -MMath::Combinatorics -le 'print "@$_" for permute grep !($i++ % $ARGV[0]), map split, <STDIN>' 7 < f.txt
--Sean 18:42, 26 June 2009 (UTC)[reply]

Handwritten notes[edit]

What is the best way of transferring handwritten notes into a computer? Tablet? Scan? Electronic stylus? Any other digitizing device?--Mr.K. (talk) 10:48, 26 June 2009 (UTC)[reply]

Assuming the notes are already written, and you don't want to type them in yourself then some form of Handwriting recognition software seems to be the only option. Given the choice between a scanner and photograph the scanner might be a better choice for multiple pages.
The other option is called a secretary..83.100.250.79 (talk) 13:52, 26 June 2009 (UTC)[reply]
Are secretaries digitizing devices? Anyway, the days in which secretaries would type a dictate are probably over and we all have to type/write our own texts. For a comparison among user-friendliness see [| here]. --Quest09 (talk) 17:27, 26 June 2009 (UTC)[reply]
Have you tried using Microsoft Onenote? Alaphent (talk) 00:24, 27 June 2009 (UTC)[reply]
Handwriting recognition software is usually pretty bad and requires a lot of cleanup. It's usually faster to just transcribe them or have someone else transcribe them. This is a situation where the software solution vastly underperforms the old-fashioned (e.g. typing) solution. --98.217.14.211 (talk) 15:18, 27 June 2009 (UTC)[reply]
This is definitely not the cheapest option, but if this is for work or school or you will be using it a lot, I would seriously consider a livescribe pulse smart pen. I had someone at my work demonstrate it to me and it is quite incredible. You can write stuff, draw stuff and says stuff to it and at the end it all just uploads to your computer. He said that there are a couple of hand writing quirks you have to get used to so it can recognise your writing better, but it's not nearly as bad as the old palms or anything like that, he said it was easy to get used to and now it hardly gets a letter wrong. If my job involved more writing I would love to have one, but I think they're over $200 so I can't really justify the spend. Vespine (talk) 01:53, 29 June 2009 (UTC)[reply]
If you have a microphone, you can try voice recognition and transciption software, although your mileage may vary. Livewireo (talk) 13:45, 30 June 2009 (UTC)[reply]
Just type them the old fashioned way, and if you really want to preserve a record of the handwritten original, take a picture or a scan. Typing the notes while you still remember the event where you took them is a good time to expand the ideas and abbreviations in them to complete sentences, etc. That makes them much easier to understand later. 208.70.31.206 (talk) 08:51, 2 July 2009 (UTC)[reply]

Portable laptop charged[edit]

I saw some portable solar laptop charged, but they only output 15V. Is that enough, if my laptop normally uses 17V?--Mr.K. (talk) 11:13, 26 June 2009 (UTC)[reply]

2V is a big difference - the answer is probably no - not enough volts.83.100.250.79 (talk) 13:53, 26 June 2009 (UTC)[reply]

Getting DSL and keeping screen name - how is it possible?[edit]

Maybe I'm misunderstanding something here; it wouldn't be the first time. But, Iwas told if I get DSL service with another provider, AT&T, I could keep the screen name from my old provider. I guess I was thinking each provider had sole ownership of the screennames, so I can't be x@aol.com if I'm not on AOL, for isntance.

Of course, I'm assuming that I could do this while also leaving AOL, and cancelling my service contract, and perhaps that's not possible.209.244.30.221 (talk) 12:50, 26 June 2009 (UTC)[reply]

You're correct; if you cancel your AOL account then you'll lose your AOL screen name and e-mail address. But if you purchase DSL (or cable modem, or FiOS, or any other broadband service), you may keep paying AOL to maintain your AOL account, and log in to AOL through your broadband connection instead of by having your modem dial up. The disadvantage is that now you're paying for both DSL and for your AOL service. If you are comfortable with AOL and it's OK with you to spend for both services, then by all means you can do that; your AOL connection will certainly be faster. At this point AOL is just another service that your computer connects to, as it would with any other website when you launch a web browser like Mozilla Firefox or Internet Explorer or Apple Safari or whatever. Over time, while continuing to connect primarily to AOL, you can experiment with free e-mail services like GMail or Yahoo! Mail, or even POP3 e-mail clients like Mozilla Thunderbird or Microsoft Outlook to replace AOL's mail functionality, and when you become comfortable with one of the latter choices and have set up a new e-mail address there, you can e-mail all your friends that your e-mail address has changed, and cancel your AOL service at that point. (Or don't, if there are services on AOL that you enjoy.) Tempshill (talk) 14:46, 26 June 2009 (UTC)[reply]
Okay, thanks for xplaining. Oh, one othe rthing - what about AIM? How do people in other countries access it? I'm just used to having it with AOL. WOuld I need to pay a fee for it, too, or would I be able to access it with DSl and with a free e-mail account?209.244.30.221 (talk) 18:35, 26 June 2009 (UTC)[reply]
You can just download it from the AIM website; see the links at the bottom of our article AOL Instant Messenger. You don't need to be an AOL subscriber to use AIM. I don't use it myself but I believe it's free to use, though I assume you will have to change your "screen name" if you cancel your AOL account. Tempshill (talk) 20:51, 26 June 2009 (UTC)[reply]

Web profit[edit]

How shock sites like Rotten.com generate profit? If these sites do not general profit, then how they operate? Does anyone fund these sites? Also how free video sharing websites like You tube generate profit? Google spent a lot of money to buy this site. But what they get in return? NewGeneticCode (talk) 13:05, 26 June 2009 (UTC)[reply]

In my limited experience, they are limited to advertising (and associated deals with regards to product placement, etc, etc) and paid backlinks. The youtube case generated a lot of stick at the time, I believe, for its monumentally large annual profit to valuation ratio. TO counter this google, has been developing ways to target in-video advertising. - Jarry1250 [ humourousdiscuss ] 13:36, 26 June 2009 (UTC)[reply]
It's also worth noting that not all web sites generate profit, and many of them don't even try to. I think Rotten.com, for example, isn't a terribly high-maintenance site, all things considered; the site design is very simple, people send them most, if not all of the material they publish, and there's not all that much to do on a daily basis. At least on the face of it, a couple of people could easily run it as a hobby without feeling too overworked. Sure, they'd have to pay for the hosting, but what the hell, most hobbies tend to cost money. Of course, Rotten does have a store. At the very least I'd imagine it at least covers the expenses they incur from running the site. They get a lot of traffic, so perhaps their merchandise sells well -- but of course there's no way of knowing that. -- Captain Disdain (talk) 14:12, 26 June 2009 (UTC)[reply]
Oh, I agree. I run a hobby site; the hosting is paid from advertising/backlinks and the occasion store sell, but the money doesn't really bother me. It doesn't make any profit really, but then again it didn't sell for hundreds of millions of dollars. - Jarry1250 [ humourousdiscuss ] 15:14, 26 June 2009 (UTC)[reply]
YouTube is chock full of ads. You can't do anything without ads raining in. Rotten is probably just cheap hosting and a hobby. --98.217.14.211 (talk) 15:03, 26 June 2009 (UTC)[reply]

java[edit]

I'm setting up some java stuff and one of the instructions says startup the mbean browser of jconsole or jvisualvm". What's mbean browser?

We have a short article on mbean. It is a browser that connects you to jconsole (Java Monitoring and Management Console) or jvisualvm (Java Virtual Machine Monitoring). It helps you set up configurations or get statistics from a Java program. - KoolerStill (talk) 14:22, 26 June 2009 (UTC)[reply]
Where do I download it?
I think if you have either the jconsole or the jvisualvm, the Mbean should be part of the package. Look in the folder your java stuff is in. There should be a file called help or readme. If you already have it partly set up, starting the browser might be on one of the menu items, possibly File or Tools.
Someone will come along who can help you more, especially if you put more details about what kind of package you are setting up.
Also please sign your posts with typing four tildes ~ (far left key on top row) because the sinebot seems to be on holiday so it can't sign it for you. - KoolerStill (talk) 17:31, 26 June 2009 (UTC)[reply]

problem[edit]

Hey,there! This C++ program gives the output that the selected room number is booked or in either case havent booked yet thus returning to back menue.Can someone sort out the problem so that it works properly,able to take the room number,customer id etc etc rather than giving the output as booked on entering any room number..Thanks

Please do your own homework.
Welcome to Wikipedia. Your question appears to be a homework question. I apologize if this is a misinterpretation, but it is our aim here not to do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn nearly as much as doing it yourself. Please attempt to solve the problem or answer the question yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. --Sean 18:45, 26 June 2009 (UTC)[reply]
I fixed the formatting of the program, for readability. To the original poster: note the <syntaxhighlight lang="cpp"> and </syntaxhighlight> tags that I added before and after your code. --NorwegianBlue talk 19:06, 26 June 2009 (UTC)[reply]
I took the liberty of show/hiding it - it's quite a few pages of code on a small screen83.100.250.79 (talk) 19:08, 26 June 2009 (UTC)[reply]
Have you tried debugging it? eg at points where it says
if (rooms[roomNumber - 1].booked == 'N')

try inserting a line of code that outputs (prints to the screen) the value of "(rooms[roomNumber - 1].booked" plus additional info that allows you to see what subroutine (proceedure or function) it's occuring in. At the same point check that the correct value of "roomnumber" has been passed.

It's not immediately obvious to me what is going wrong - perhaps a minor syntax or parsing error?
Clearly from your description something must be going wrong on the if then else conditions - so you can focus your attention there.
If in doubt, add more brackets to logical conditions to avoid any curious behaviour regarding operator precedence.83.100.250.79 (talk) 19:23, 26 June 2009 (UTC)[reply]
Also note that this isn't really what a C++ programmer would call a C++ program. It's a C program, with some elements from C++ (cout etc), but it's mostly PODS (plain old data structures), fixed size arrays etc. --NorwegianBlue talk 19:35, 26 June 2009 (UTC)[reply]
One thing that looked odd to me was in MakeReservation() there's a call to MainMenu at the end of the IF ... ==='N'
Not sure if that is necessary/right/wrong - but it seems an odd call - don't see how it would mess up the logical conditions though..?83.100.250.79 (talk) 19:47, 26 June 2009 (UTC)[reply]
Also shouldn't there be a call to Initialize in main ?83.100.250.79 (talk) 20:05, 26 June 2009 (UTC)[reply]
(ec)Lucky for him it IS just C or I couldn't help him. He's not a C++ programmer, he's a student apparently. - KoolerStill (talk) 20:10, 26 June 2009 (UTC)[reply]
(ec)This is how you do it. Break your program down into simple sentences. Your main processing says "IF room is not booked, fill in booking details, then mark room as booked, ELSE display that it is already taken". If I understand you right, you are saying it is always showing every room as being booked? This means it is always falling through to the ELSE. So it is obviously never finding a room that == 'N'.
Start looking for why there is no such room. Where do you put 'N' on the rooms? You declare a function called void Initialize(), which seems to do just that. BUT WHERE do you actually RUN that function? Anything called 'initialize' should be the 'initial' (first) thing to do. Try calling it as the first thing in (main). I also suggest 'B' for Booked and 'V' for Vacant might be better status flags to use. - KoolerStill (talk) 20:10, 26 June 2009 (UTC)[reply]
The call to MainMenu seems to be a GOTO to return to the menu of actions once a booking is taken; loop control must be next semester. - KoolerStill (talk) 20:22, 26 June 2009 (UTC)[reply]
Well,basically I'm neither a programmer nor a student just an amateur..I'm not figuring out why the program is falling through to the ELSE.Why is it not finding the room=='N'? what i think if that

loop is working then it should not even go to ELSE for any room entry because ---rooms[i].booked = 'N';---It's kinda confused.Give me any suggestions please.

OKAY, we thought student because it looks like a course assignment. I guess you get the same in self-study textbooks.
I tried to step you through it before, up above. It is falling through because it finds no room that is 'N'. That is because you are not marking any room as 'N' to start with. You can initialise every room before you run the rest of the program. OR you can just blank out all details for a room when the people leave. I think your void Initialize() probably does that.
A simple solution would be to change .....roomNumber - 1].booked == 'N' to say ...roomNumber - 1].booked != 'Y'. So instead of looking for "no" you are looking for anything that is not "yes".This way you don't need to set them to 'N' when you start.
Oh and PLEASE sign your posts here. Just put four tildes ( ~ on the top left key just below Esc) - KoolerStill (talk) 11:20, 27 June 2009 (UTC)[reply]
As KoolerStill and others have suggested above, the problem is with the rooms[?].booked. It is only ever set to a value of "Y", but the program sometimes checks for a value "N". How does it ever get set to "N" (hint: the Initialize() function is never called and there is no other function to declare a room available for booking again). Don't believe me? - run the program as is, and choose "5 - List All" from the menu - the DisplayList() function will display the value of rooms[?].booked for every room. Astronaut (talk) 12:07, 27 June 2009 (UTC)[reply]
Thanks a lot! I got the whole program and it's running properly except one thing.I didn't understand what the pointer const prompt is doing in the following function.


int GetRoomNumber( const char * const prompt )

{ int roomNumber;

do { cout << prompt << " (1 - "<<MAX_ROOMS<<"): "; cin >> roomNumber; } while ( roomNumber < 1 || roomNumber > MAX_ROOMS );

return roomNumber; }

what will be the alternative if we don't use pointer prompt?--121.52.148.13 (talk) 05:51, 30 June 2009 (UTC)[reply]

How can a question be contracted?[edit]

Like the question above this? —Preceding unsigned comment added by 88.1.123.111 (talkcontribs)

Help:Collapsing. Algebraist 19:27, 26 June 2009 (UTC)[reply]
Or take a look at the wiki-markup in the question above this, by clicking the "edit" link. --NorwegianBlue talk 19:31, 26 June 2009 (UTC)[reply]

Like this:
{| class="wikitable collapsible collapsed"
text or whatever here
|}