Shrink or enlarge images at the command line

GIMP can do just about anything to an image but it can be time-consuming to fire it up just to resize an image. For ultra-quick manipulation, consider Imagemagick, a command-line image manipulation program. It doesn't come installed by default and you'll need to install it via Synap-tic (search for and install imagemagick). Once installed, the convert command should be used with the addition of the -resize command option. For example, the following will shrink filename.bmp to half its original...

Quickly create graphical text banners

Tip 219, on page 254, discusses using the figlet command-line tool to create ASCII banners of words but if you want to quickly create text banners as a image file, perhaps for use on websites or presentations, you can use GNOME's font preview tool. It isn't really designed for this but appropriation of existing commands is the beauty of Linux You need to specify the text, plus which font to use (including its full path), and the output filename. The following will create a banner saying 'Ubuntu...

Instantly search Google for any word or phrase

Have you ever been reading a document and wanted to look-up something in Google In Firefox you can just highlight the word or phrase, right-click it, and select Search Google. However, what if you're reading, say, a PDF file Or a man page in a terminal window A very simple but effective solution is googlizer, which you can install using Synaptic. Once installed, it's added to the Applications Internet menu, so you'll have to manually drag and drop it to a blank spot on the panel for quicker...

S3 Make Ubuntu safe for children to use

Ubuntu can be as kid-safe as any other operating system with a little work. Essentially, two things can be done. First you can create a new restricted user account for the child (or children) that stops them from doing anything that might break the system, or attempting to bypass any protective measures you enact. Secondly, you can install a web filtering system so that nothing that isn't entirely child-safe gets through when they're using Firefox.10 The first thing you should do is create a...

Administer Ubuntu using a web browser from any computer or operating system

Webmin is some fun software designed to let a user administrate his her system using a web browser. The web browser can be running in the computer itself, or on another computer on the same network or even the Internet (provided the network is configured correctly). Webmin is geared around server configuration, but it still offerers one or two tools for more humble users. Unfortunately it isn't contained within the Ubuntu software repositories, and must be downloaded from the Webmin site....

Sharpen images at the command line

If you followed Tip 154, on page 197, and Tip 11, on page 72, you'll already have come into contact with Imagemagick. This command-line program can do just about anything to images and you can learn more about it by viewing its man page (man imagemagick) or viewing its website Perhaps one of the most useful functions it can perform, besides file format conversion and resizing, is to sharpen an image. Almost all images look better when sharpened, particularly if they're being shrunk for use in...

Rename many files at once aka bulk rename

Have you ever been out with your digital camera and then returned home to find yourself with lots of files with names like IMG_0159.jpg, IMG_0160.jpg, IMG_0161 .jpg, and so on And have you then gone through one-by-one renaming them with something relevant Well, there's no need to ever do that again because Ubuntu can come to the rescue There are a handful of ways of bulk renaming files at the command-line but many are quite involved and you'll need to remember a chain of commands. To save the...

Install Google applications

As with Windows and Macintosh, Google has released a series of downloadable applications for Linux Google Earth, Picasa and Google Desktop. Google Earth allows you to spin around the globe looking at satellite photographs and planning routes between locations. Picasa lets you catalog and tweak photographs on your hard disk and then upload them to online photo albums provided as part of your Google account. Google Desktop lets you organize and search your files, as well as quickly search your...