Lossless digital zoom in digital cameras

These last two weeks I've been on my honeymoon holidays...really really nice. I have been quite disconnected from computing or technological news, but I learned a useful feature of my digital camera that was absolutely unknown to me: the lossless digital zoom. Let me explain a little bit...

I have had several digital cameras and many of them had digital zoom. As this nice article explains, the digital zoom makes the illusion of having a longer optical zoom by making larger a small part of the original image the optical zoom gets (through interpolation). The result is a softened image (with less definition), not so clear as a normal one and not very useful in general. That's why I always disabled the digital zoom of my cameras. But, these holidays I discovered a great trick some modern cameras use to be able to enhance your optical zoom with a special kind of digital zoom that has no degradation...Is that magic ? No, but it's amazing anyway.

The trick is called "Smart zoom" by Sony and "Safe zoom" by Canon, but it's implemented by other cameras and it's pretty simple to implement. If you have a camera with many megapixels but you make a picture with less resolution than the maximum, your camera can actually make a picture with the maximum resolution and then crop it to the small part you have selected (by zooming with the digital zoom). In other words, the camera traditionally has had to make a large image from the small part selected by the digital zoom, and it had to "invent" the information it didn't have by interpolation; but now, it doesn't have to "invent" this information, because it actually has them (just selecting a larger resolution for the image). This article explains it much better than me, so read it (specially the "Smart zoom" part). This special zoom has limitations, it only can work if the image resolution you select is smaller than the maximum and the factor of zoom without degradation is not unlimited (in my camera I can "only" double the optical zoom range when I select a 1600x1200 resolution)...but it's enough for me.

The technique is equivalent to make a picture with a maximum resolution with the optical zoom and crop it yourself at home to the size of image you really wanted from the beginning, but it has some advantages:
  • You don't need to do this process at home (the camera does it for you), so this saves your time
  • You save space in your camera, because what is saved is the cropped image, not the lareg one (at maximum resolution)
  • You can choose the composition of the picture while you do it (I prefer it)
So...I have enabled the digital zoom in my camera again, it's worth it.

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Personal Wiki (TiddlyWiki)

This weeek I have discovered a great tool to organize my ideas or little tricks in an easy but powerful way: TiddlyWiki. It's a personal Wiki page, written in Javascript...you don't need any web server to publish it. You can add short "tiddlers" (short entries with a title), associate tags to them (in order to classify them), and that's all. You can search your tiddlers easily, open all the tiddlers with a given tag, arrange them in the page the way you want, etc.

I use Freemind a lot, specially to write documents, because I can organize and move my ideas very easily while writing them, but when I need to store tips or solutions to computing problems I prefer this TiddlyWiki tool, it searches very well and tags are great to classify easily with less effort.

Try it out!

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Linux in your Palm

Yes !!! You don't need to buy a new Palm, to wait for the new model that uses Linux as its OS...you can simply download some binaries, follow some easy steps and....woohooooo...you have Linux in your Palm !!!!

I have a Palm TX and it works really good, it doesn't have Wifi support yet but overall it's great and promising.

Try this out ! (but make a backup of your data before, just in case).


Some small nice utilities for Windows

At my work I have a Lotus Notes account, but not the Lotus Notes client, so I must have the browser open all the time, just to be notified of e-mail or calendar events. As I don't like having it open (it eats resurces) and it's annoying to click on a dialog each time the browser session is about to expire, I use some useful utilities.

For the e-mail events, I have POP Peeper. It is a small application that notifies you when new e-mails arrive. It can handle more than one account and you can choose the kind of alert signal you prefer: a flag in the system tray, a dialog, etc.

For the calendar events, I use Personal Reminder. It's a very simple application that allows you to insert entries to remind, when you want to be reminded and the repetition of notification if you need it (to remind you every day, every week, etc.).

I love these kind of small apps: simple to install, small size, simple and intuitive to use, ...

Good intro to Grub

If you need to use Grub and understand its basics, there's an excellent introduction called "Grub from the ground up". I never understood the syntax of Grub, and when I was face to face with the Grub shell I didn't know what to do and its help information was a bit hard to understand at first sight.

This article introduces you to Grub easily, teaching the very basic information you should know to be able to boot a PC with Grub and understand how a 'menu.lst' file is oganized.