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May 14

Default Firefox fonts

Something happened and my fonts got changed, the default to Times New Roman 16. I've changed the size to 12, which looks approximately right, but the letters in an edit's comment field and the subject/headline of this question are tiny. How can I reset it all to the standard defaults? Clarityfiend (talk) 03:28, 14 May 2015 (UTC)[reply]

Resolved

Is dosbox a emulator or a virtual machine?

Is dosbox a emulator or a virtual machine?201.79.82.81 (talk) 12:54, 14 May 2015 (UTC)[reply]

DOSBox is an emulator. An emulator is a kind of virtual machine, which (despite the similar names) is quite different from hardware virtualization. -- Finlay McWalterᚠTalk 13:05, 14 May 2015 (UTC)[reply]

Urgh. On reading the virtual machine article, it seems people are still using "virtual machine" both to mean a software-invented pretend computer (like DOSBox or the Java Virtual Machine) and the hardware-invented pretend sub-instance of a real computer (like VirtualBox or VMWare). -- Finlay McWalterᚠTalk 13:30, 14 May 2015 (UTC)[reply]

DOSBox performs software simulation of individual i386 CPU instructions, so it is a full CPU simulator as well as a running instance of an operating system. The brief status summary hints at some implementation details: for example, if you dared to build and run DOSBox on a PowerPC platform, your simulated x86 processor's math functions would not be bit-exact. (Rather, the simulated 387 Floating Point extensions to the x86 processor would be implemented using libc and libm and would execute as native floating point instructions in the real machine's architecture).This means that DOSBox is not a pure virtualization of the CPU. Such bit-exact machine simulations are very rare, because they are so dramatically low-performance; but they do exist. For example, people who design CPUs wish to simulate the CPU at the gate-level and instruction level: this would be design verification (a standard subtask of EDA in the normal workflow to design digital logic and build it on silicon). It may be possible to emulate a full operating system and application software on top of such a virtual machine, if you're willing to wait a few days for the system to boot. Nimur (talk) 13:45, 14 May 2015 (UTC)[reply]

A long time ago I worked at a company which designed its own CPUs. The chip designers ran gate-level simulations of the whole device on clusters of workstation-grade machines. Thus simulated, it took a day or so just for the CPU to boot. It had hitherto not occurred to me that CPUs actually did anything in order to "boot"; I was wrong. -- Finlay McWalterᚠTalk 13:56, 14 May 2015 (UTC)[reply]

And then there is the system described at [ http://dmitry.gr/index.php?r=05.Projects&proj=07.%20Linux%20on%208bit ]: a system that emulates a 32-bit ARM CPU/MMU on an 8-bit ATMega microcontroller. It takes two hours to boot Linux ( https://www.youtube.com/watch?v=nm0POwEtiqE ) and about a minute to respond to a command. the designer calls it the "cheapest, slowest, simplest to hand assemble, lowest part count, and lowest-end Linux PC." --Guy Macon (talk) 14:15, 14 May 2015 (UTC)[reply]

Is the expression "Data product" ?

What does "data product" (Data_analysis#Data_product) actually mean? Is that different from an app or program (offline or online) running independently? Aren't all programs data products somehow? Besides that, why call it "product" which leads to confusion since it implies the result of processing, and not a program processing data and suggests that it's proprietary? --Llaanngg (talk) 17:39, 14 May 2015 (UTC)[reply]

You are apparently thinking that "product" in the business sense (something that may be offered for sale or trade). This term is using the mathematical "products" (the result of multiplying). It is correct that you are not really multiplying to data items to get a data product, but it is a similar concept. You are taking some data items and producing a new data item. The data product is the new data item (the product of the operation performed on the old data items). An example that I do a lot is BMI. Give me two data items (height and weight) and I can produce a new data item (BMI). As you can see, the app that I wrote to do this work is not the data product. The result of the app (and no - it isn't really an app. I don't work for Apple and I don't call everything I write an app) is the product. Further, the result of all processing is not a data product. If I count how many records meet a criteria, I get a number. But, that number isn't a data item that is of reasonable use for the data environment, so I don't feed it back into the data environment. So, it is not a data product. 209.149.114.204 (talk) 18:46, 14 May 2015 (UTC)[reply]

How can I strip the background music from an mp4 file?

I have an mp4 video of 3+ hours that I have to watch for educational purposes. The voice on it is OK, but it has a very repetitive background music. Just think tetris music, but worse, all 3+ hours long. Is there a way of eliminating the background music and keep the voice?--Llaanngg (talk) 17:42, 14 May 2015 (UTC)[reply]

This is sometimes known as "vocal removal" or "vocal isolation"- I can't find any specific WP articles, but it's a subclass of digital signal processing - here are some instructions on how to do it with Audacity [1]. This kind of thing can sometimes be done passably well with a "one-click" algorithm, but it requires some human art and skill to get it done right. SemanticMantis (talk) 17:56, 14 May 2015 (UTC)[reply]

It's much trickier to remove background music using the "noise reduction" facility in Audacity, but it's worth a try. If the background music is high pitched and the voice low pitch, then a simple filter might remove it, though you'll lose some sibilants. If you post a short sample of the mixture somewhere, then we could experiment, or you can download Audacity yourself. Dbfirs 20:20, 14 May 2015 (UTC)[reply]

→VLC media player --Hans Haase (有问题吗) 12:41, 16 May 2015 (UTC)[reply]

Image file becoming Fuzzy

Hello!

I have an image file containing alphabets that are very small, it becomes fuzzy when I ‘zoom in’, any workaround available?

Mr. Prophet (talk) 19:26, 14 May 2015 (UTC)[reply]

It would help if you posted the image file in question.--Aspro (talk) 19:33, 14 May 2015 (UTC)[reply]

Its an old image file from my HDD -- Mr. Prophet (talk) 21:53, 14 May 2015 (UTC)[reply]

Probably not without some decent effort, and even then, it might not be enough to allow you to read the text. See super resolution. If you got the image off the internet somewhere, there is a decent chance a higher image resolution version is available elsewhere. Try putting the image in to TinEye or Google's "search by image" to see if you can find other, better copies of the same image. This of course will not work if you took the photo :) P.s., this is one reason why WP and many other places prefer vector graphics over raster graphics for many purposes - the former never become blurry, no matter how far in you zoom. It is also possible that image tracing may help by converting your raster to a vector format, depending on your goal and the nature of the image - this is not usually used as a technique to get more sharpness out of images, but it can sometimes result in slightly more readable small text SemanticMantis (talk) 19:41, 14 May 2015 (UTC)[reply]

Everything of my google is in different language. Inkspace apparently supports 'image tracing', it sound similar to 'Adobe illustrator', the 'vector graphics' thing. I have illustrator, I opened the file went to 'Object' menu, fiddled with the 'Image Trace' feature's features after selecting the complete image, no luck... How would I convert a file from 'raster' to 'vector' using 'Adobe illustrator'?

There are a a bunch of converters however in the internet, which one would be the best, what I could keep for future use...?

Mr. Prophet (talk) 21:53, 14 May 2015 (UTC)[reply]

Here's instructions on how to "trace" a bitmap/raster and get a vector image in Inkscape [2]. Is your goal to be able to read things that you couldn't before, or to have it look better when you zoom in? This might help, but it might not, at least it is free and fairly easy. SemanticMantis (talk) 13:29, 15 May 2015 (UTC)[reply]

Read things I couldn't before. Hope it works... Thanks. -- Mr. Prophet (talk) 18:33, 15 May 2015 (UTC)[reply]

If they get fuzzy when you zoom in (as opposed to "jaggy"), that sounds like subpixel rendering or a related method. StuRat (talk) 04:29, 15 May 2015 (UTC)[reply]

I don't know what it is, the image looks fine in the ordinal shape, the words are very small, say 'font size' between 1 to 5, the writing becomes blurry when I zoom in... -- Mr. Prophet (talk) 06:10, 15 May 2015 (UTC)[reply]

The methods I refer to color each pixel differently. This method looks terribly fuzzy when you zoom in. StuRat (talk) 14:11, 15 May 2015 (UTC)[reply]

Lol. -- Mr. Prophet (talk) 18:33, 15 May 2015 (UTC)[reply]

See dpi and display resolution. For faster loading a webpage, use thumbnails, downsized versions with less pixels of the pictures. For a detail view, you need the full resolution. If you don't have, use inkscape, load the picture and draw a vectorbased layer over the original bitmap. I can be done automatically, press Ctrl+Shift+B, but may have not the best results. When using it as font, better use a font editor, but do a search first to save huge unneccessary work. --Hans Haase (有问题吗) 07:21, 16 May 2015 (UTC)[reply]

Guys, what shall I download? I'm on 32-bit, the '.msi' is 80Mb, '.exe' is 40Mb. I've read through them, what confused me was the information about 'they could only be a type of file which will insist/download other files from the internet, meaning I have to have a full internet connection... This is the first time, in my life time, probably, I actually saw two or more options in one place for one software. The 'installer (exe)' file is preferable as I'm on 'payg: Kbs' as long as it doesn't tell me to download more files... -- Mr. Prophet (talk) 18:42, 16 May 2015 (UTC)[reply]

I'm still using the old 0.48 version, 32 bit only. The installer will install the whole program on a computer. The portable app is - I guess, the programm and ressource files in an archive to run from a USB flash memory stick, portable harddrive or similar file system ressource. If the internet connection is not the problem, download a stable 32 bit version. An installer or download differs from real memory (RAM) usage. --Hans Haase (有问题吗) 10:15, 17 May 2015 (UTC)[reply]

I can download adult video clips after the end of the month. Thanks!

-- Mr. Prophet (talk) 19:40, 17 May 2015 (UTC)[reply]

It is weird that there are two installers. They use different installation systems (the exe is NSIS, the msi is Microsoft Installer) but seem to install the same stuff. Neither one needs Internet access. I don't know why the msi file is twice as large. Use the exe. -- BenRG (talk) 05:35, 18 May 2015 (UTC)[reply]

I'll be downloading it tonight hopefully. Thank you. Btw, I know what you mean...first time for me too. -- Mr. Prophet (talk) 06:05, 18 May 2015 (UTC)[reply]

Thanks friends Thank you for the assurance too, I needed it... Take care. -- Mr. Prophet (talk) 05:55, 18 May 2015 (UTC)[reply]

File doesn't load up, installed and waited... -- Mr. Prophet (talk) 10:54, 18 May 2015 (UTC)[reply]