There is also older stuff, which probably no one is interested any longer in.

Concatenate movies automatically

Make your presentations / lectures more lively with PowerDraw

Then PowerDraw is the tool for you.
It is particularly useful when giving presentations / lectures using a ModBook (this is a tablet MacBook).
On the right you can see a picture how it looks like

Here is an overview of the features:

• Overdraw mode: while switched on, all mouse clicks and dragging are intercepted by PowerDraw to create line drawings. If overdraw mode is switched off, then only PowerDraw's buttons are active; all mouse events in other areas of the screen go to the application underneath, as ususal.
• Two buttons for stepping forward/backward in your presentation (this is particularly useful while overdraw mode is on).
• Buttons to skip to the next/previous slide, no matter how many animations there are.
• The GUI is fairly minimal, so as not to intrude too much; it is also quite efficient (hopefully), so that switching between drawing mode and click-through mode, and between different drawing colors is as quick as possible.
• PowerDraw remembers what you have drawn over each slide; so if you go back a slide, the drawings you have made there will be displayed again. And it does not matter whether you go back via PowerDraw's button, or via Powerpoints own user interface (e.g., backspace, right click, etc.)
• PowerDraw never intercepts keyboard events, so key clicks will always go to Powerpoint (or whatever application is in focus at the moment). This is a safety net. (Another reason is that the ModBook has no keyboard at all.)

Installation: just download the disk image and move the application inside to your Applications folder.

Usage: just run PowerDraw, the rest should be straight-forward.

Prerequisites: Mac OS X 10.5 or higher and, if you want to use it with Powerpoint, Powerpoint 2008.

Donation: if you find yourself using this app sometimes, please consider making a donation (see the button at the bottom of the configurations sheet); all kinds of donations will be highly appreciated!

License: please notice that I put PowerDraw under a copyright and license that basically says it's free for personal use but not for commercial use.

Test program showing how to create a window that is always on top, transparent, and still gets mouse events in Cocoa (on Mac OS X)

• a transparent window using Cocoa that is always on top of all other windows;
• a button with which one can toggle the mouse behavior on the "glass canvas";
• while the button is pressed, the transparent window captures mouse events; while the button is not pressed, the window is click-through;
• the toggle button always receives mouse events.

Make the iPhone work with congstar

I solved this with the following procedure:

1. Download this Carrier Bundle: congstar_de.bundle.zip and unzip it.
2. Copy it over to your iPhone:
   scp -r congstar_de.bundle root@169.254.xxx.xxx:"/System/Library/Carrier\ Bundles",
   where 169.254.xxx.xxx is the current IP address of you iPhone. (I usually do this by creating a private network on my Mac.)
3. Ssh into your iPhone:
   ssh root@169.254.xxx.xxx
   and
   cd /System/Library/Carrier\ Bundles.
4. Make the new carrier bundle the one to be used in Germany on the T-Mobile network like so:
   # mv 26201 26201_old
   # mv 26206 26206_old
   # ln -s congstar_de.bundle 26201
   # ln -s congstar_de.bundle 26206
5. Reboot your iPhone.

The iPhone still doesn't show the carrier's name at the top left (next to the signal strength), and you still get a blank carrier name in Settings -> Carrier, where it should say D1 or T-Mobile ... but, oh well ...

I've got an iPhone 2G with firmware 2.1, jailbroken and unlocked.

I relied on a number of most valuable sources for the above procedure: http://www.volkspost.info/carrierbundle_pwn2/ , http://en.wikipedia.org/wiki/Mobile_network_code , http://hackint0sh.org/forum/showpost.php?p=274640&postcount=20 (the plutil was already installed on my Mac).

Batch Convert a Number of Movies with Quicktime

A few Basic Shapes as OmniGraffle Stencil

Move Off-Screen Windows to the Main Screen

Here is a little variation; the difference is: all windows that are more or less off-screen (no matter how much) are moved back so that they are completely on screen (if possible).

Counting Polygons in VRML / X3D

Simplex Noise

Klausur-Auswertung

Folgende Dinge berechnet das Sheet automatisch:

• Pro Student: Summe der Punkte und Note,
• Histogramm über die Gesamtpunkte,
• Histogramm über die Noten,
• Durchfallquote,
• Für jede Aufgabe ein Histogramm der erreichten Punkte,
• Farbkodierung der Noten,
• auf einem zweiten Sheet eine anonymisierte Tabelle der Noten, so daß daraus sehr einfach eine HTML-Tabelle erzeugt werden kann;

• Pro Student: die erreichten Punkte in jeder Aufgabe;
• Je einen Schwellwert für die Note 1.0 und 4.0;

Bemerkung: Beim Öffnen muß man "enable macros" anklicken (ansonsten funktioniert die Aktualisierung der Farbcodes der Noten nicht; alles andere funktioniert aber weiterhin).

Make Proceedings from many PDFs

Print Your Mac's IP

These two IPs might be different if you are behind a router or a NAT device. The script is written in Python (which is installed on your Mac).

Find Duplicate Files on the Mac

Details: Find files that are (byte-wise) identical, but are (possibly) scattered among different directories. This might happen, for instance, if you copy a large directory tree and (accidentally) resolve symbolic links during the copying.
The output (on stdout) consists of two lists (mainly): first a list of files that have been found to be equal, one file per line, and the last file within each group of equal files gets a period appended; second, the list of duplicates sorted by complete pathname.
Special files, like .DS_Store, are not considered. Also, special directories, like CVS, are skipped. In addition, only regular files are considered, no symbolic links or other special files.
The implementation uses a number of optimization tricks to speed up the search. On my G4, scanning a directory tree consisting of 40,000 files in total, containing 7,000 duplicates, took about 3 minutes.

And here is the source code as XCode 2.4 project.

Screen Saver for the Mac

So, here is ArtSaver version 2.1. Some of its options and features are the following:

• Keeps a persistent database of all the images found in the specified directory tree or iPhoto album. This has the following benefits:
  • handles huge image databases,
  • displays images immediately when started, and,
  • does not "exercise" the disk every time it gets invoked.
  
  I have tested my screensaver with directory trees containing about 150,000 images (scattered among about 300,000 other files).
• Use all images in a directory tree (minus the ones that are excluded by other options, see below), or all images in one of your iPhoto albums.
• You can review the previous images (cursor keys), pause the slide show (space bar), or have ArtSaver show the current one in Finder (return key).
• Options include:
  • the speed of the gradual zoom-in and out (Ken Burns effect);
  • the duration how long an image is displayed;
  • whether or not the path of the image should be displayed, too. (instead of the complete path, ArtSaver can also display just the filename.)
  • whether or not ArtSaver should use Spotlight for finding all images in a given directory tree (with Spotlight it is faster, but sometimes Spotlight does not find all the images, or none at all, and then the other option can be quite valuable);
  • many many more ...
• You can specify constraints to exclude certain images:
  • the minimal size in pixels (for instance, thumbnails);
  • the minimal size in bytes;
  • a list of file patterns; if the path of an image matches one of the patterns, it gets excluded (for instance, "index prints").
• You can review the file names that ArtSaver has displayed afterwards (see the Help button in the Options pane).
• Observes the EXIF-orientation tag

Installation: as usual, download the disk image, open it (if your Mac hasn't done it for you), and double-click on ArtSaver.saver.
(If you want to install it "by hand", then copy ArtSaver.saver either to the directory    /Library/Screen Savers    or    ~/Library/Screen Savers    in your home.)

ArtSaver should work out-of-the box with its built-in defaults. However, in ArtSaver's Options pane you'll probably want to specify the directory where ArtSaver can find the images (default = ~/Pictures), and whether and how ArtSaver should display the image name. All other options in the other two sections probably work by default, but they are there if you need to change them.

When you close the Options pane, ArtSaver recursively scans the directory tree containing the files, and saves the list of images in a database (its plist file). After that, every time ArtSaver gets invoked, it will just read this list, and never has to go through the whole directory tree, which can be a huge time savings, if there are many images. Scanning a directory tree of 300,000 files (150,000 of which are images) takes about 1 minute on my Intel-based Mac Book Pro as of 2008 (both with or without using Spotlight).

The Change Log at the bottom of the Read-Me explains the changes over the previous version.

If you enjoy this screen saver, I would really appreciate a donation via paypal. (It would also keep me motivated to make further enhancements ;-) )

Please notice that I put ArtSaver under a copyright and license that basically says it's free for personal use but not for commercial use.

And here is the source code as XCode 3.2 project. And the single source file (for Google's database ;-) ).

If you have any comments or suggestions, please don't hesitate to send me an email at zach in.tu-clausthal.de.

Convert CSV to Mail Aliases