ocrodjvu = OCRopus (tesseract) + DJVU

It is a small command-line tool to easily convert your image-only DJVU files into image+text DJVU files. In Debian testing, there are language packages for (in no specific order) German, English, French, Spanish, Vietnamese, Brasilian Portuguese, Dutch, and Italian. The original tesseract-ocr software includes training data & code, so it should be (at least in theory) easy to add more recognition languages.

Production: see http://www.howtoforge.com/how-to-set-up-apache2-with-mod_fcgid-and-php5-on-debian-etch – it is for Debian Etch (which is old-stable), but many of the steps apply equally well to Debian Lenny (current-stable). Also, this is a very basic guide, as if you are going to host multiple sites from multiple clients, you most definitely will need some hosting control panel.

Development: see http://www.ruzee.com/blog/2009/01/apache-virtual-hosts-a-clean-setup-for-php-developers. This setup works very well, unless you need to create several virtual hosts every day – in which case necessary actions could be partially scripted.

If you get this message when opening vignettes:

Error in openPDF(vif) :
getOption(‘pdfviewer’) is ”; please use ‘options(pdfviewer=…)’

and you are tired of running this command every time:

> options(pdfviewer=”okular”)

then you should check if your system-wide Renviron file has proper PDF viewer set:
Read the rest of this entry »

PwdHash uses your “single password” to create a site-unique password (by making a one-way hash of your password and the site’s domain).

Although I’m not using “single password for all sites”, PwdHash does look very convenient.

Regular expressions (regexps) are powerful indeed. But debugging non-trivial regexps is a burden even if you understand how regexps work, and remember most (if not all) regexp syntax.

Miscellaneous tools exist to ease this task. This post was inspired by redet’s comparison of regexp helper tools – it could be sufficient to read only that, if you’re going to try the mentioned tools yourself. Otherwise, read on.
Read the rest of this entry »

Today Google celebrates the invention of the barcode.

To help in this celebration, you can make a barcode with your site’s address (there is at least one more at barcodesinc, but at the moment of writing it is painfully slow).

I find these parameters nearly optimal:

• Type: Code 128-B
• Styles: Draw value text
• Size: 234×60 (half-banner size)
• Xres: 1
• Text font: 5
• Value: bogdan.org.ua

If you wish, you can also exactly replicate today’s Google logo – which says “Google”, as you could have guessed.

You can place this barcode on your “souvenirs” – pens, cups, t-shirts. Many phones now have barcode scanners (e.g. Nokia E71), so put this code onto your namecard.

Read on to learn about matrix barcodes.
Read the rest of this entry »

Screem HTML/XML editor has tag-specific auto-complete, and is a nice editor for web-developers (at least as long as Quanta is not available for Debian testing).

However, version 0.16.1 is very unstable, and dies with

***MEMORY-ERROR***: screem[5527]: GSlice: assertion failed: sinfo->n_allocated > 0

As a workaround (initially suggested for the highly similar Firestarter crashes), try running screem with this command:

G_SLICE=always-malloc screem

Too bad last development version of Screem is dated March 2006.