Wikipedia:Reference desk/Archives/Computing/2006 October 22

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October 22

Changing codec format of .avi files

I have an oral presentation to present for a subject at school and as part of it I intended upon playing two video clips relevant to my talk. I took the small clips (~30seconds) from a larger file (~2 hours) using virtualdub. My problem is that the computer I will be using at school for the presentation lacks any media codecs apart from those inherent in Windows. The details of the two clips are below. As I cannot install the codecs on the school computer (for "security" reasons) I would like to know a way that I can change the codec format of these files so that they would be able to run on a system with NO downloaded codecs. Ideally, the output format would be one that I can imbed into a powerpoint presentation.

First File Format  : AVI Info  : Audio Video Interleave Family  : RIFF File size  : 7.91 MiB PlayTime  : 52s 10ms Bit rate  : 1276 Kbps Writing application  : VirtualDubMod 1.5.10.2 (build 2540/release) Writing library  : VirtualDubMod build 2540/release

Video #0 Codec  : DivX 5 Family  : MPEG-4 Codec settings  : BVOP PlayTime  : 52s 10ms Bit rate  : 1183 Kbps Width  : 532 Height  : 222 Aspect ratio  : 2.35 Frame rate  : 23.976 fps Resolution  : 8 Chroma  : 4:2:0 Interlacement  : Progressive Bits/(Pixel*Frame)  : 0.418

Audio #0 Codec  : MPEG-1 Audio layer 3 Family  : MPEG-1 Info  : MPEG-1 or 2 layer 3 PlayTime  : 52s 854ms Bit rate  : 80 Kbps Bit rate mode  : CBR Channel(s)  : 2 channels Sampling rate  : 48 KHz Resolution  : 16

Second File Format  : AVI Info  : Audio Video Interleave Family  : RIFF File size  : 1.83 MiB PlayTime  : 28s 445ms Bit rate  : 539 Kbps Writing application  : VirtualDubMod 1.5.10.2 (build 2540/release) Writing library  : VirtualDubMod build 2540/release

Video #0 Codec  : DivX 5 Family  : MPEG-4 Codec settings  : BVOP PlayTime  : 28s 445ms Bit rate  : 446 Kbps Width  : 532 Height  : 222 Aspect ratio  : 2.35 Frame rate  : 23.976 fps Resolution  : 8 Chroma  : 4:2:0 Interlacement  : Progressive Bits/(Pixel*Frame)  : 0.157

Audio #0 Codec  : MPEG-1 Audio layer 3 Family  : MPEG-1 Info  : MPEG-1 or 2 layer 3 PlayTime  : 28s 902ms Bit rate  : 80 Kbps Bit rate mode  : CBR Channel(s)  : 2 channels Sampling rate  : 48 KHz Resolution  : 16

I didn't actually read through that whole list but your best bet is to make it into a .wmv file for Windows based system, preferably with the Movie Maker. I hate both, but, hey, it's not my presentation. --Wirbelwindヴィルヴェルヴィント (talk) 02:33, 22 October 2006 (UTC)

Since you already have virtualdub you can use it to re-encode. Open the video in virtualdub, make sure "Video->Full processing mode" is checked, then select a codec in "Video->Compression...". Some of the codecs are old and what would be considered low quality but for short clips that shouldn't matter that much. I don't know which codec to recommend, sorry. The "Configure" button in the codec selection window allows to change encoding quality in some codecs. Optional step: if you want to re-encode sound too, check "Audio->Full processing mode" and select an audio codec in "Audio->Compression" (the default "Audio->Direct stream copy" will copy the audio track as is, leaving the audio codec unchanged.) Then "File->Save as avi" to encode. You can select a short range of the video first to check how the result looks or play with codec settings. Weregerbil 06:56, 22 October 2006 (UTC)

NO pop up script

Hello, I have a webpage in which there are links that are pop-up windows. Is there a html script in which I could disable having pop-ups? Note that i don't want to make them to load in my main window, i just want to disable the pop up on my page. Thanks --(Aytakin) | Talk 02:25, 22 October 2006 (UTC)

You say that you have the page - which makes me assume you made it. So, remove the popups that you put there if you don't want them. Then, you say you don't want them to load in the page and you don't want them to pop up. What do you want them to do? All in all, your question is far too confusing to answer. --Kainaw ^(talk) 04:40, 22 October 2006 (UTC)

It's much more likely that he's using a free web-hosting service that forces popups onto his page. There are ways to block popups using JS and (I think) advanced HTML, but the popups are what funds your free-hosting service, so you're likely to lose it if you attempt to block them.  freshofftheufoΓΛĿЌ  05:43, 22 October 2006 (UTC)

Yes, and there are popup blockers you can download onto your computer, but that would have the same problem. StuRat 11:31, 22 October 2006 (UTC)

Hello and thanks for the responses, that's the case!! I don't want the those links on my page to pop up and as  freshofftheufoΓΛĿЌ  mentioned there is a way using Java or HTML, can you tell me where i can find such script?--(Aytakin) | Talk 22:04, 23 October 2006 (UTC)

Try a google search like this one.  freshofftheufoΓΛĿЌ  09:52, 26 October 2006 (UTC)

Simply by adding an "alert" script to your page will make these pop-ups become pop-under... I did that after my free hosting banned me for using scripts to block their pop-ups, you could use the alert script to say welcom to my page or to ask if they're over the age of 13 and such, once the alert script pops up, the popups will go to the toolbar, and when they click ok, they see your page only... It's annoying to have an alert script, but at least you gain that much control over your page... If you want true free hosting, check out http://www.hostinglagoon.com you fill out surveys using whatever info you want, this site gets paid for sending you there (no money, no credit cards, no personal info other than name and address) then they give you domain names, hosting gaming site credits... I did it, and had my domain and hosting up and running in less than 24 hours. The free domain and hosting I got is http://www.gesellman.com check it out and see if there's any popups or anything... 24.240.24.220 02:00, 29 March 2007 (UTC)

Running a wikibot

I'd like to run a bot on a small Wikia wiki, but I have no programming skills. All I need it to do (for now at least) is to move a list of pages to a new namespace, and to italicise all instances of a proper noun. I'd like to run the bot of my own machine (a Windows, tee-hee!) for a few minutes a day at least until the job is done. I've asked before here and received some answers, but none were particularly helpful. So again I am seeking instructions on how to implement such a bot. Hyenaste ^(tell) 06:25, 22 October 2006 (UTC)

Have you read WP:BOT and the accompanying articles? Dismas|^(talk) 10:17, 22 October 2006 (UTC)

Yes, but nearly all of the associated pages involve the politics of setting up a bot in Wikipedia instead of helping getting one to function. The only page I've found that offers any help is meta:Using the python wikipediabot, but it doesn't say whether it works for Wikia or anything else except for a few lines of code scattered around. Hyenaste ^(tell) 17:42, 22 October 2006 (UTC)

Moving application/binary directories' locations in Ubuntu/Linux as a whole

Hi,

My filesystem partition is running out of space with everyday. I want to move some big software directories to another partition, then put a symbolic link in its place. Is this feasible? Thanks! --inky 07:35, 22 October 2006 (UTC)

Yeah, it should be. A symbolic link can point to any file/directory, regardless of the partition, device, or file system that it's on. Depending on how you're doing it, you might want to do this through the fstab, though a symlink will probably suffice in any case. -- Consumed Crustacean (talk) 08:01, 22 October 2006 (UTC)

Hidden/Private folders on XP

Multiple users all work on the same computer. How can I have a folder that only one user has read/write permissions. (And yes, I tried to sell the "just install linux" solution, but they wouldn't go for it.) --Alecmconroy 07:44, 22 October 2006 (UTC)

This (ignore #2 unless for some reason you're dealing with zips), or if you want maximum security, TrueCrypt. -- Consumed Crustacean (talk) 07:54, 22 October 2006 (UTC)

For XP Home, Log into an administer account under safe mode[F7 during boot] and edit the permissions by group as you would normally in Windows 2000. For XP pro/*-home, http://compnetworking.about.com/cs/winxpnetworking/ht/winxpsfs.htm use that. Jrabbit05 05:11, 29 October 2006 (UTC)

Software Radio

In software Radio, what is the analogy to decode FM?

You mean such as internet radios transmitting through the wires? The analogy to decode FM would be the same, I believe, since both transmits through a medium, and goes through a Digital-to-analog converter, and out the speakers. --Wirbelwindヴィルヴェルヴィント (talk) 16:14, 22 October 2006 (UTC)

Video Compression

Any idea about which coec is the best in terms of compression and quality???

Well I'm not sure by benchmark comparisons but, based on its popularity, MPEG-4 (and the many codecs based on it) seems to have reached a good balance between size and quality. See video codec for some examples of codecs based on MPEG-4. —Mitaphane _talk 13:38, 22 October 2006 (UTC)

Computer Lockup

The problem arises when I play games, for apparently no reason. I startplaying the game normally and press a key, the game does the action corresponding to that key e.g. going forward, then I take my finger off the key. But the player does not stop, he still executes the action as if the button were actually pushed. At this point, whenever I try to press NUM-Lock, CAPS-Lock and SCROLL-Lock, their LED on the keyboard doesn't change. Then one of two things happens:

1. The player stops doing the action the NUM-Lock Led changes, and I can resume playing.
2. The player continues on going until a BSOD pops up with a BAD_POOL_CALLER error, dumping physical memory to disk.

Could anyone help me on this? It's really annoying... Thanks in advance.

My specs are:

• Processor Pentium 4, 1.8 GHz
  • L1 Code TLB 4 KB pages, 4-way set associative, 32 entries; 4 KB/4 MB/2 MB pages, fully associative, 64 entries
  • L1 Data Cache 8 KB size, 4-way set associative, 64 byte lines, sectored
  • L1 Data TLB 4 KB/4 MB pages, fully associative, 64 entries
  • L2 Cache None
  • Trace L1 Cache 12 KµOPs, 8-way set associative
  • Unified L2 Cache 512 KB size, 8-way set associative, 64 byte lines, sectored
• Graphics Card ATi Radeon A9600PRO from ASUS

--Danielsavoiu 09:46, 22 October 2006 (UTC)

A BAD_POOL_CALLER error in Windows is a device driver conflict. It sounds like some driver that's getting used in your game is causing the problem. Try updating your drivers for devices(Vid card, sound card, controller, etc) that the game uses. That might do it. —Mitaphane _talk 13:45, 22 October 2006 (UTC)

Canon Pixma IP1600 on Linux?

My grandmother recently bought a Canon Pixma IP1600 inkjet printer and I set it up for her. In the process, I thought it would be cool to buy one for myself also. Only problem is, I am using Linux (and only Linux) in my computer, and at least according to the user manual of the printer, Canon isn't even aware that Linux exists. Does anyone have an idea if the printer would still work? It uses a USB connection. I'm also thinking of upgrading my Linux installation from Fedora Core 3 to Fedora Core 5. JIP | Talk 11:44, 22 October 2006 (UTC)

"Canon isn't even aware that Linux exists" Haha! :-) I know what you mean, it seems to happen far too often when you want to buy a product. Gah, why can't they just stick to some standard and make it work for everyone, even on systems they actually haven't heard of? I'm afraid I have no answer to your question. Isn't "printer over USB" standardised by now? —Bromskloss 20:22, 22 October 2006 (UTC)

The only thing I found after a quick Google search is [1] which says you can use the free driver from [2] up to 300 DPI (if you try to use more than that it writes a logo to the paper unless you pay for the registered version). --cesarb 20:49, 22 October 2006 (UTC)

Try using CUPS (Common Unix Printing System). I used this on my parents' Mac to print to their Canon printer and it worked perfectly. --Canley 05:41, 23 October 2006 (UTC)

Of course you could always try it on your mothers computer. If you don't want to install Linux there (and why not?) you could use a live cd. DirkvdM 06:53, 23 October 2006 (UTC)

My grandmother's computer, actually, not my mother's. But I found that the Canon Pixma IP2200 has Linux drivers available, and is only 19 € more expensive. I might buy that instead. JIP | Talk 09:28, 23 October 2006 (UTC)

Removing weapons from Unreal Tournament GOTY

Hi @ll. Is it possible to make all weapons (except translocator) not working (not displaying either in HUD or in level) and not working? Emptying the class definitions and recompiling with UnrealEd didnt help; google doesnt find any real helpful n this topic. Greets, HardDisk 14:03, 22 October 2006 (UTC)

Yeah there's some weapons mutator (I think it's called "weapons mod" so it will probably be hard to find) that lets you replace any gun with any other available to UT. Very useful for mixing and matching the old infiltration weapons (which are hellishly hard to find these days) with the UT weps. Theres an option to replace the weapon with "None" IIRC so you could just replace all the weapons with nothing and turn on the translocator in the normal UT options. I'm surprised that unlinking the class definitions didn't do it though.. did you just delete them or did you actually clear out the code that calls them? --froth^{T C} 21:02, 22 October 2006 (UTC)

I couldnt delete them (not possible, as it seems), so I wiped everything out except the "class XXX extends Weapon"; then I started UT and all weapons were working. HardDisk 15:25, 23 October 2006 (UTC)

Intel Processors

What is the highest-end Intel Processor available for consumer home desktops? And why do some newer processors have slower clock speeds than older ones? Jamesino 16:50, 22 October 2006 (UTC)

Clockspeed is not necessarily indicative of the processor's performance. Intel used to market their Pentium's clockspeeds heavily because they were so stupidly high (compared with AMD, whose CPUs still matched or bettered Intel's). This is probably backfiring somewhat right now because their new CPUs do often clock slower, despite actual performing better. See Megahertz Myth.

The Intel Core 2 CPUs are probably the best consumer CPUs right now. They're faster than AMD CPUs of the same price, they've got less heat output, less power consumption, and they overclock well. The super fancy Conroe XEs are the fastest variety of those (see the article), but they cost a lot. -- Consumed Crustacean (talk) 19:58, 22 October 2006 (UTC)

What is the Hyper-Threading they talk about? Jamesino 20:02, 22 October 2006 (UTC)

Hyper-threading. Intel's current CPUs don't support it, only the old Pentium 4s do. So, it's not that important. -- Consumed Crustacean (talk) 20:08, 22 October 2006 (UTC)

Hyper-threading is a way to let a CPU pretend to be two separate CPUs, each running a separate execution thread. The second trhead gets to use the cycles that would otherwise go to waste due to stalls in the execution of the first thread. Intel cannot seem to make up its mind as to how effective this is, but the overally gain is relatively modest. By contrast, most of the Core 2 devices have two complete CPUs on one chip. Intel has also announced a quad processor, (two chips, each with two CPUs, inside one MCM package.) If they ever do get around to re-implementing Hyper-threading, a quad-core package would execute 8 threads -Arch dude 21:15, 22 October 2006 (UTC)

Whistling Monitor

My girlfriend's CRT monitor is producing a whistling sound occassionally when it's on. The whistle is usually a constant sound, but does come and go. There is no change in the picture quality when the whistling begins. Can anyone explain what the problem may be? --Kiltman67 18:22, 22 October 2006 (UTC)

I like Wikis. There seems to be an answer in this one. One possible fix is to change the monitor's refresh rate. Besides being extremely annoying it's not necessarily a sign of any problem, though I have seen a couple CRTs get very loud the day or so before they break. -- Consumed Crustacean (talk) 19:47, 22 October 2006 (UTC)

You can see things get loud? Are you a synesthete? DirkvdM 07:45, 24 October 2006 (UTC)

[3], #28. :P. -- Consumed Crustacean (talk) 15:45, 27 October 2006 (UTC)

Errors introduced by processor change?

What I have is an implimentation of Conway's Game of Life in C. I compiled it and it ran perfectly on my University server. I have since brought a second computer to school with me for the sole purpose of using it as my C compiler, so I can crash my own computer with massive memory leaks rather than a departmental server. I took the exact same code from the department server and transfered it to my little "server." I compiled and ran the code, no errors. But to my great dismay, the results are different. This is what I should get, and do on the department server:

0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0
0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0
0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0
0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 1 1 0 0 0 0 0 0 0 1 1 0
0 0 0 1 0 0 1 0 0 0 0 0 1 0 0 1
0 0 0 0 1 1 0 0 0 0 0 0 0 1 1 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0
0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0
0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0
0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
# of live cells = 24

On my own "server" I, incorrectly, get the following:

1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0
0 1 0 1 0 0 0 1 0 1 0 0 0 0 0 0
0 1 0 1 0 0 1 0 0 1 0 0 0 0 0 0
0 0 1 0 0 0 0 1 1 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
# of live cells = 15

As a test, I also compiled and ran the code on this very computer, only to obtain the incorrect result as well. The only commonality I can find between my "server" and this computer is that they are both AMD procesors, and the department server is more than likely an Intel processor. Is there an argument in gcc specifically for AMD processors, besides those for optimization? The basic form of my code can be found here. I know my comments are over the top, but that may be helpful here. Any ideas as to what the problem could be? --yaninass2 | talk 23:46, 22 October 2006 (UTC)

Where are you initialising the automatic array a? -- Finlay McWalter | Talk 23:57, 22 October 2006 (UTC)

a takes integers, is then passed into the eval function, where it sets the beginning pattern of the game in the basis array. What goes into a changes depending on the pattern, obviously. What is used for this particular version is:

for(i=0; i < 5; i++){
a[i]=0;
}
a[5]=2<<5;
a[6]=7<<5;
a[7]=5<<5;
a[8]=2<<5;
for(i=9; i < 16; i++){
a[i]=0;
}

Hope this explains my code a bit more. --yaninass2 | talk 00:24, 23 October 2006 (UTC)

If you're not sure if the university server has an Intel processor or not, have you considered Endianness? Intel and AMD are both little-endian, but if the server is a SPARC or PowerPC processor then it may be compiling differently (correctly by the looks of it) on a big-endian machine, especially if you're messing around with bits and arrays (I've had a similar problem with gcc on my pre-Intel Mac and a friend's PC coming up with different compilations). There's some code in the article to detect Endianness if you want to check. --Canley 05:28, 23 October 2006 (UTC)

Just looking at your code, it might be this bit where you're masking the significant bit:

basis[row][loc] = (a[row]>>(15-loc))&0x00000001;

--Canley 05:34, 23 October 2006 (UTC)

Nice one, didn't think of that. I ran the test function on both machines and both returned 0, meaning they are both Little Endian. Good suggestion, but alas, not the solution to my problems. --yaninass2 | talk 13:21, 23 October 2006 (UTC)

I ran your code (on yet another LE machine), and it works fine as far as I can tell (I made traffic lights). I even checked that none of your array references were out of bounds or were reading uninitialized data. The only thing I can guess is that your "code varies by pattern" is somehow broken, implementation-dependent, or machine-dependent. In general, it seems more likely to me that you are doing something undefined (like indexing beyond an array) which happens to give different results on the two machines than that you are actually experiencing machine-dependence (unless you're reading your patterns from a file in some system-dependent way or so). If you post your pattern code, it might be analyzable. --Tardis 16:07, 24 October 2006 (UTC)