Feb 182009
 

The fonts that LaTeX uses by default (called “Computer Modern”) are very elegant, and are one of the great reasons to use LaTeX for typesetting documents. Frustratingly, I’ve been having difficulty lately with my pdfviewer (epdfview and sometimes xpdf) not displaying these fonts well in pdfs I’ve created using LaTeX.

Adobe acroread has been able to do a better job, but who wants to use such a slow and bloated piece of software just to quickly view a pdf? At least the pdfs have printed properly, so up till now I haven’t been too worried.

The solution, which I found at a page encouragingly called “High quality PDF output from LaTeX and TeX”, is profoundly simple. It simply involves telling LaTeX to use the scalable font rather than the older bitmap version. Add these two lines to the preamble:

\usepackage[T1]{fontenc}
\usepackage{ae,aecompl}

and you’re done.

Feb 022009
 

One of the really great things about storing photographs digitally is the ability to embed all sorts of information about the image in “metadata” within the file. When I shot film, I carried a notebook around with me that I tried to record exposure settings in (I was usually too lazy); I wanted to be able to learn from experience by looking at the settings I used to take a particular image. Digital cameras have trivialised this process, as they embed the exposure settings within each photograph.

But digital metadata is able to store much more than just the camera settings. In particular, it is becomming increasingly common to store location information (collected automatically by GPS). This is not so much to remind the photographer where they took the photo (most of us are pretty good at remembering that with reasonable precision), but it allows entirely new methods of displaying and browsing sets of photos.

Over the last few months I have experimented with various data acquisition and image display techniques for geo-tagging. This is a growing field, and so I’m sure there’s a lot more for me to learn. However, here are my findings and a quick demonstration of the results. Continue reading »

Jan 142009
 

Last week I had reason to duplicate some video DVDs.  Yes, it was legitimate; I wanted copies of personal video footage to share with family.  After fiddling around a bit I found a very straighforward way to do this task using simple GNU/Linux tools.

The first step is to copy the DVD to the hard drive (I only have one DVD drive).
cat /dev/sr0 > dvd.iso
where /dev/sr0 is my DVD device.

Then, after changing to a blank DVD, simply
growisofs -dvd-compat -Z /dev/dvd=dvd.iso
and it worked.

Aug 152008
 

Last week I learnt a very important lesson: a “backup” is not actually a backup if it is the only copy you have, it is at most an archive. In the process of tidying up the files on my external “backup” hard disk I deleted a few directories of photos from the beginning of this year. As I pressed the Enter key I was sure that I had a copy of those photos still on my laptop; but fractions of a second later I experienced a piercing wave of doubt. It was already too late.

After checking my laptop and finding that the doubt was justified, I remembered with relief that before heading over to Europe I had copied all my photos onto DVDs and left them in my office at uni (just in case something our house burnt down or something). I went to sleep mostly certain that I my accidentally deleted files were safe on discs at uni.

As you probably suspect, I did not have a copy of the photos on DVD. My DVD backups only went to the end of 2007, and I had deleted files from the first 2 months of 2008.

It is not a tragedy, as the main photos of consequence were from ASA Convention and I do have the best of my photos on the official DVD. However, it provided me with significant incentive to learn about data recovery on ext3 formatted partitions. I’ve included some of my discoveries below. Continue reading »

May 222008
 

While browsing some photos on Flickr the other day I came across an interesting artistic photography technique. It is known as the “Orton Effect” after a guy called Michael Orton, and involves superimposing a focussed image and blurred image (both overexposed) of the same scene. The effect is a mixture of sharp detail and blended colour that produces somewhat ethereal and emotionally engaging images. Orton developed the technique using slide film and physically mounting 2 images in a single slide frame, but it is easy to reproduce the effect with digital post-processing. Continue reading »

Mar 062008
 

In preparation for my trip to Europe, I needded to free up some space on my hard disk. It was a great opportunity to find out how to burn data DVDs.

I found this DVD creation article on the Gentoo wiki, and the following command worked brilliantly for me:

growisofs -dvd-compat -Z /dev/sr0 -joliet-long -R -V "<volume_name>" dvd/

where /dev/sr0 is my device and dvd/ the directory containing the desired contents of the DVD.

Feb 292008
 

I am an avid user of bash, the standard command line environment (technically “shell”) for GNU/Linux. In today’s graphical-rich computing culture, many people notice my command terminal and assume I must be a stubborn nostalgist of the digital dark ages. The truth is that the command line allows many regular tasks to be performed more efficiently, and makes some things possible that are simply not available any other way.

The extra power of the command line comes at the cost of learning its ways, which are not always obvious or self-explanatory. Today I found a very good guide to increasing bash productivity using vi editing commands, and leveraging the command line history to save time and effort. Both of these articles have very good downloadable cheat-sheets.

Nov 012007
 

On my ThinkPad, I scroll by holding down the middle mouse button and moving the little trackpoint joystick. This means that it is easy to couple a little bit of sideways scroll with vertical scroll, which is not usually a problem. In Firefox, however, the default settings are for a left/right mouse scroll to go back/forward a page. This is most unsatisfying.

The solution has been published online in a multitude of places, but to save me needing to search for it again I’ll mention it here. Continue reading »

Sep 042007
 

One of the things that frustrated me last year as I edited my honours thesis was text elements in inserted graphs. Axis and tick labels were unavoidable, but making them look consistent with the document text was not easy. I wish that I had found this article about making plots using Octave, gnuplot, and LaTeX, because the psfrag package provides a perfect solution.

It replaces text in an eps file with its own LaTeX formatted text. This allows, for instance, elaborate mathematical formulae to be displayed anywhere on the graph. It also allows axis and tick labels to be replaced with text that exactly matches the font and size used throughout the document – even if document wide settings are changed after the graph has been created. Continue reading »

Jul 312007
 

For a while now I’ve been giving all my digital photos filenames that are meaningful to browse, useful to organise and easy (automated) to implement. The date is used to facilitate easy sorting, a few keywords are added to ease browsing, and the timestamp is added to ensure uniqueness. Thus, I end up with filenames like 20070731_a_great_photo_1425-39.jpg. Continue reading »