Omar Abo-Namous » Programming

Pythonic way of opening more than one file at a time

admin — Sun, 08 Jan 2012 13:26:43 +0000

Some hours ago, someone asked on StackExchange about a more pythonic way to represent the following code: PLAIN TEXT PYTHON: with open(read_csv, 'r') as read_file: with open(write_csv, 'r') as write_file: reader = csv.reader(read_file) … Continue reading →

New Year’s Python Meme 2012

admin — Fri, 23 Dec 2011 19:46:49 +0000

Following Tarek Ziade's Python Meme, here's my try: One small note first, though. 2011 has totally been a python year for me. I actually discovered python for myself and for professional applications in October 2010 and have been using it … Continue reading →

Visualizing OpenCL computations within OpenGL

admin — Sat, 06 Aug 2011 14:17:57 +0000

I've been fiddling with OpenCL computations for different projects in the past. One such project is the implementation of a specific triangulation algorithm for a structured light measurement system. The other one is a parallelized implementation of a 3d binary … Continue reading →

Interactivitiy with Mayavi and python callback

admin — Mon, 22 Nov 2010 23:31:37 +0000

Today i found out that i may use figure.on_mouse_pick(function) to get a callback on a mouse_pick on mayavi-objects and it opened up a whole new way of dealing with mayavi-scenes. Right now, i'm trying to do a semi-automatic point cloud … Continue reading →

PyOpenCL performance booster

admin — Fri, 05 Nov 2010 01:03:56 +0000

One common task in projected fringe analysis is the phase extraction of a phase shift. Four phase shifted sin-waves are projected unto a surface and recorded by the camera. I'm not going to get into the details of the algorithm, … Continue reading →

Residual of planefitting using svd

admin — Sun, 24 Oct 2010 22:58:04 +0000

Note to self: Find out about residuals of planefits using singular value decomposition. And while you're at it: find out, how least square fitting works with singular value decomposition anyhow. Right now - as with any transformation matrix bigger than … Continue reading →

Trying out Python for image manipulation and matlab-alternative?

admin — Tue, 21 Sep 2010 13:34:49 +0000

Learning new languages can be sometimes a little bit frustrating. Mostly, because you not only have to learn the syntax and conventions of the language but mainly because initially it's hard to know, what kinds of libraries are available - … Continue reading →

Contact Form for wordpress

admin — Tue, 23 Feb 2010 15:39:32 +0000

For a client of mine, i've been using the PEAR-package HTML_QuickForm which is 'superseded' by now and isn't compatible to php 5.2, whereas the followup package HTML_Quickform2 is still in alpha state. Since the client switched his server and that … Continue reading →

Scavenged pen-plotter Roland DG DXY-990

admin — Fri, 20 Nov 2009 13:00:01 +0000

Yes! I've managed to scavenge an old pen-plotter that was obviously gathering dust down in the basement of our institute. Last time i've seen such a plotter was in the 1980s at the institute where my father used to work. Back then, it was a paper-feed pen plotter that was used to plot various measured data online.

The DXY-990 plotter shown below can hold eight pen at the higher left part and moves on an xy-plane using two stepper motors which control a ribbon each. Each initialization process involves finding the lower-left corner which seems to be offset from the x-position of the pen. The plotter can be loaded with a paper size slightly bigger than DIN A3. The paper is held by a controllable static charge (wow! when did this technology disappear?) so that it doesn't move when the pen is hovering or scratching on it.

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Creating Gray-Code sequences using gimp

admin — Mon, 15 Jun 2009 09:00:32 +0000

I needed to implement gray-code sequences for a fringe projection system i'm trying to build. To avoid hard to understand and not really intuitive C-code, i used gimp to produce the projection images. In this article i'm going to document the code used.

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