Wikipedia:Reference desk/Archives/Computing/2007 June 9

Computing desk
< June 8	<< May | June | Jul >>	June 10 >

Welcome to the Wikipedia Computing Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.

June 9

Question about pixel art colors

On a pixel art collaboration some users togheter made this,

http://img519.imageshack.us/img519/5535/xxisocitymosaicpjcolabdgr8.gif after this some others user uploaded more blocks to this colaboration, but one user when making this made the picture darker (by saving in PNG maybe????) (see the picture: http://img527.imageshack.us/img527/4851/huhju3.png )

There is a program that revert the brightness to the brightness that the picture was??

I think that i saw on one collaboration that some user made the picture darker and then another user reverted the brightness of the picture to the brightness that the picture was, but the picture was large so i don't think that he made himself pixel by pixel, so thats is why i am asking this.

Haha, amazing! I worked on this exact piece and I was the guy who kept correcting the brightness! I just used Photoshop's brightness adjustment until the colors matched the originals. I'm guessing the problem is that some users were saving the image with an embedded ICC Profile, while others were not, so the gamma was being altered each time. — Kieff | Talk 06:00, 9 June 2007 (UTC)

Also the first version is in GIF and there's no reason to expect the colors to render exactly the same as in PNG. Always save in PNG or (God help you) 24-bit bitmap --froth^t 11:55, 9 June 2007 (UTC)

That's usually a good advice for other forms of graphics, but for pixel art, with small palletes, one would find that working with GIF is a lot more stable than with PNG, since different editors treat PNG differently (embedding or ignoring ICC profiles and whatnot). GIF just plainly stores colors as-is, so there's less room for deviation. — Kieff | Talk 12:21, 9 June 2007 (UTC)

last resort

hey?i recently installed a tv card on my coputer then i decided to uninstall it.i just wasnt using it that often then i tried to re install it again.first i couldnt find it.then i decided to run he cd that came with the device.theres a wizard that appears that informs me that i already have an od version of the program installed.then the wizard dissapears without installing.on the desktop there apears an icon of a t.v card version 3.0.mine originally was 2.0. i dont have the hardware for the 3.0 and when i try to open it it says read registry error.when i go to the add remove programs the tv card program cant be removed.when i click it nothing happens.am considering runnin xp again.how can someone totally remove a program that cant be removed from the add remove programs tab.the device manager afirms that everything is okay with my hardware.i think my computer is nuts av even tried system restore nuthing happens. 2.incase everything fails and i run xp again i need some pointers on how to partition a hard disk nicely.i have 80 gb.am using partion magic.

All you need to partition your hard drive is your Windows XP Setup CD. There's plenty of tutorials on how to do this with the CD, but I'll give you a semi-detailed outline. First, you'd want to backup any data you want to keep. Then you'd insert the CD, restart, and follow the CD's instructions to get to the partition window. Delete your existing partition(s), then create new partitions of whichever size you want. If you are running XP and Linux you'll want more than one partition, but if you're just wanting XP then you'll only need the one. Then, pick a partition to install to, wait for it to install everything, then install all your drivers/updates/programs again. Have fun. SMC 10:27, 9 June 2007 (UTC)

Linux WiFi?

Hi. Any idea what the gnome network applet is trying to say here?

It seems to indicate that it's got a good signal strength to the network (4 bars), but it doesn't seem to be usable for web browsing. Same with WEP or unencrypted. Ojw 11:28, 9 June 2007 (UTC)

Not sure of the specifics, but keep in mind that just because you have good signal strength and is unencrypted means you can connect and get Internet access. There can be filtering and security at other layers.

The Speedtouch it's trying to connect to is configured as "Allow New Devices: New stations are allowed (automatically)" (as opposed to 'registration required' or 'no new devices'). Ojw 11:37, 9 June 2007 (UTC)

IE 6

My browser keeps dropping cookiees, what should i do?13:59, 9 June 2007 (UTC)172.145.110.115

Make sure the cookie policy is set to allow in the options. or they could of expired Lmc169 14:06, 9 June 2007 (UTC)

How to rip zoomed images?

I'm trying to access the high resolution image file that opens within a javascript widget at the following address:

http://www.eternalegypt.org/EternalEgyptWebsiteWeb/HomeServlet?ee_website_action_key=action.display.element&story_id=&module_id=&language_id=1&element_id=60532

Is there some way to get past the zoom feature in the javascript (javascript:openNamedWindow('viewer','widget/viewer_popup.jsp?language_id=1&name=4278&element_id=60532&mode=1n',670,480)) to get hold of the original file?

Paul James Cowie 16:25, 9 June 2007 (UTC)

Looks like it's a quicktime plugin, which means everything will be embedded. You can either download the "Pro" version of quicktime and then Right Click -> Save Source, or print screen the image. I'd suggest the latter. If anyone else has any ideas, this would be of help to me too :). JoshHolloway 16:55, 9 June 2007 (UTC)

I have Quicktime Pro, so I tried rightclicking to Save Source..... but this is not an option. Not sure whether this is a QT plugin.... I think the reference to QT in the page source might just be a sniffer for QT in general. The mechanics of the image viewer seems to be in Javascript. Josh, not sure what you mean by your other suggestion, to "print screen" the image.... Anyway, still stuck. Any additional suggestions? Paul James Cowie 17:05, 9 June 2007 (UTC)

Print screen — Matt Eason ^{(Talk • Contribs)} 17:15, 9 June 2007 (UTC)

As far as I can tell its in 9 parts: [1] [2] [3] [4] [5] [6] [7] [8] [9]. Any attempts at typing a full link for the 3000x3000 seem to have failed, so you can download all 9 and use an image editing program to piece them together. :) -wizzard2k ^(C•T•D) 17:22, 9 June 2007 (UTC)

Programming a PLL

Greetings. I have a PCM file containing a (slightly noisy) carrier wave at approximately 19 kHz, sampled at 44.100 kHz with a 16-bit resolution. I would like to generate a clean sine wave at exactly the same frequency – how should I do this? I've been trying to implement a simple PLL by slightly modifying the frequency of my sine wave whenever it has more zero-crossings in a certain amount of time than the carrier, but it is too unstable. Thanks in advance for any help. ›mysid (☎∆) 17:01, 9 June 2007 (UTC)

A small amount of noise can easily turn one zero-crossing (say, going down) into three (down, up a little, down again), so counting the number of zero-crossings is a bad idea. Why not use correlation? Multiply each sample of the carrier wave with the corresponding sample of the sine, and optimize it so their sum is as great as possible. You're basically tuning the sine by eliminating beats. —Keenan Pepper 19:38, 9 June 2007 (UTC)

Thanks! That led me to read a lot about correlation. What do you mean by optimization (i.e. is it trivial to do it)? And by sum, do you mean product? ›mysid (☎∆) 08:31, 10 June 2007 (UTC)

I found it out by myself and it works like a dream. Thanks! :) ›mysid (☎∆) 22:25, 11 June 2007 (UTC)

Upconverting low-res videos on a PC.

I'm running a 1600x1200 monitor. Is there an app, plugin, or anything I can use to upconvert my 640x480 videos to a higher resolution without getting awful quality? I know I can stretch the image, but some things (like the PS3 and certain DVD players) can stretch the image to 720i/1080i and use some effects to make it look decent. Pesapluvo 20:03, 9 June 2007 (UTC)

Nope. You can't get higher quality from transcoding, only lower quality. --h2g2bob (talk) 01:57, 10 June 2007 (UTC)

I meant upconverting while playing back, not re-encoding the file at a higher resolution, by the way. Pesapluvo 04:06, 10 June 2007 (UTC)

This may not be of any help, but what you're talking about is image scaling by bilinear interpolation, which is probably what PS3 and the others do. Your computer may be stretching the image using nearest neighbor interpolation, which is fast but looks pixelated. ›mysid (☎∆) 08:20, 10 June 2007 (UTC)

I don't think any media players out there uses Nearest Neighbour. PC had been doing this for ages, way before the gimmicky DVD and PS3 upsampling came along, just maximize the window using a good player like VLC media player and it will automatically upsample it for you, but it certainly won't look like HDTV. --antilived^{T | C | G} 08:45, 10 June 2007 (UTC)

You can use the Haali Renderer (part of the Haali Media Splitter program) to resize videos using Bicubic interpolation using your graphics card (no CPU load). FFDShow supports Lanczos and Bicubic, but Lanczos might not go fast enough unless you're on a very fast computer. If you don't need to do it on playback, the Blackman Resize function in Avisynth is probably the best resizer there is. —Dark•Shikari^[T] 05:12, 11 June 2007 (UTC)

Pinnacle Studio Ultimate Ver. 11

I just bought a Pinnacle Studio Upgrade Ver. 11 Ultimate to be used in Windows Vista. My previous upgrade was Ver. 10.5 for Windows XP. I tried to install under Vista, and during the installation, the program asked me to hold down shift key, insert the previous version, and click ok. I followed all that, but it kept asking me to do the same with prior version and only to talk about comparability issue later. What have I done wrong? Chailai 20:24, 9 June 2007 (UTC)

Never mind the message – I got it figured out – used the earliest version (not an upgrade) when prompt and be sure to cancel the auto start. Don’t start the installation unless you have a minimum of two hours to work on this. Chailai 15:36, 10 June 2007 (UTC)