Computer Guide

Compressing images

by George Skarbek - 25 November 2008

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Q: I have a question regarding zipping JPEG files. I tried to zip a JPEG photo and found that the size did not reduce that much. Is this correct, and is so is there another way to reduce the size of JPEG's in order to email them?

A: There are several ways to reduce the size of photos without a noticeable loss in quality but using compression tools such a WinZip is not the answer. This is because the picture format such JPG is efficiently compressed and the best WinZip do is to reduce them by about 3 percent. BMP files can be compressed very substantially using WinZip.

Your choice depends on what your recipients will ultimately want to do with the images. If they just wish to view them on the screen, then by resizing the image you should be able to reduce a 2 MB file to less than 10% with no visible difference on the screen. If they wish to print postcard size prints then about an 85% reduction in size is possible. However, if they want to print A4 or larger size then only a small reduction is image size may be possible.

For simply viewing on a screen I suggest that you re-size your large image to 800 x 600 or 1024 x 768 pixels and change the DPI (Dots per Inch) setting to 72. However, always Save As with a different filename so that you always retain the original image.

If you do not have a suitable image manipulation program that can re-size images then you can download a tiny free program called Irfanview. It is free and can be downloaded from: . This tiny program can very much more, including edit the images, sharpen them, re-size them, do batch conversions, view thumbnails, create slideshows that can be burned to onto a CD and even more.


Monitoring downloads

Q: The "Toolbox" provided by iiNet is very useful for keeping track of Internet use as a whole, but my problem is that there are 5 computers on a LAN in my house - including 2 teenage boys!  Need I say more?  The problem is that when our monthly entitlement runs out and we get shaped - who was using it all up is the question!  So is there any program that you know of which is capable to tracking individual use of multiple computers on a LAN - preferably on ONE of those computers (i.e. mine, the father of the 2 boys).

A: I am not aware of any software that when installed on one computer that can monitor network activity on all others but there are a number of programs that will monitor and record network usage.

The free program NetMeter is a good way of watching and recording.  See: for details. It must be installed on all computers and then you will have to go to each computer either daily, weekly or monthly to find out who is using the most data. Dumeter is very good commercial program from and it costs US $50 for a family pack.

Note that these programs measure all activity in the Ethernet port so if you copy large files between the computers, that data will be recorded in the totals.


Firefox favourites

Q: I am using Mozilla Firefox as my web browser on my laptop and have added a considerable number of web pages to my bookmark section. What I now need to do is transfer the URLs to my desk top via a memory stick but cannot find where the list of book marked pages are in Firefox. They certainly are not in my favourites section which is where I first looked. Could you tell me where to find the list?

A: In XP, unlike IE, Firefox stores all the favourites in one file called Bookmarks.html in the folder C:\Documents and Settings\User name\ Application Data\Mozilla\ Firefox\ Profiles\strange name.default.  The best way to find it may be to search C:\Documents and Settings\Your name and look for Bookmarks. This is the only file that you need to backup.

If you are running Vista then the location is C:\Users\User Name\AppData\ Roaming\Mozilla\ Firefox\Profiles\bj3csqlw.default


Making a DVD player zone free 

Q: Whilst in the US early last year, I bought a Sony Vio notebook. Everything works great except for one problem. I found out in Australia that I am unable to play any DVD movie outside the US zone on the notebook. How can I reset to computer to play DVD from all zones?  If I cannot reset the computer, is there some free software that I can access to fix the problem?

A: The best way is to find out the make and model of the DVD that is in the notebook. Do this from Click on Start, Settings, Control Panel, System, Hardware, Device Manager and look in CD/DVD devices. Having established the manufacturer then use Google to search for: manufacturer DVD region free. There is a high probability that you will find some free software to reset or even remove the region setting.


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