Posts – Page 4

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Low-cost USB temperature logging

UPDATE (2015):

These days, if you want to measure temperature, humidity and other environmental variables cheaply, there's no need to mess around with unreliable USB-sensors. It's more reliable (and not that much more difficult) to simply use a Raspberry Pi or an Arduino and connect sensors directly using I2C, SPI …

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How to merge video files

How to merge/join/combine/concatenate multiple video files

Say you have a collection of short video clips made with a telephone or digital camera, and you want to join them into a single video file. How can you do this without having to re-encode everything?

In Ubuntu Linux:

What …

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Extracting TIFF pictures from MS Word for Mac documents

Recently I tried to open several old MS Word files created on a Macintosh in OpenOffice.org on my Ubuntu machine. The text part of the documents got converted just fine by OpenOffice.org Writer, but the images became rather messed up. Anything that had been imported as a bitmap …

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Data Clustering

I've written a fast perl/PDL implementation of UPGMA data clustering for very large datasets. The problem is that existing clustering packages have difficulty handling datasets with more than a few thousand data points. Especially the distance matrices tend to become a problem. For example, clustering the outcome of a …

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Ubuntu Repository

NEW PPA REPOSITORY:

The original repository was getting a bit outdated. It was trailing a few Ubuntu-releases behind and only had i386-builds. You can still use it for Hardy or manually download packages (see below) for installation on newer releases, but I'm no longer going to maintain the old repository …

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Hardware 3D acceleration on an ATI Radeon 9600 mobile

UPDATE (2010-08-25): This article describes how to configure Ubuntu 8.04 LTS (Hardy Heron) for stable 3D-acceleration and desktop-effects with ATI R300 series (Radeon Mobility 9600 and similar) GPUs. On recent Ubuntu versions (such as 10.04 LTS) this should work out of the box, and making modifications to xorg …

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iBlue 747 and other MTK GPS devices

Instructions on how to get an i-Blue 747 or similar bluetooth GPS-datalogger (based on an MTK chipset) to work on Ubuntu and on an Intel-based Mac using the Java-based BT747 control software. Interestingly, someone has even made a Japanese version of the MacOS X howto on his/her blog (むぁっく日記 …

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Downgrading packages using yum

In Linux-land there are two major package management systems, APT/dpkg and YUM/RPM. My favourite of the two is definitely APT, which is mostly used by Debian and derivatives such as Ubuntu. Yum is used by Red Hat and derivatives such as CentOS, Fedora and SME, and works just …

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:Zolid/Kworld DVD maker (USB EM2861 video capture device) on Ubuntu Linux

Last year I bought a cheap :ZOLID High-Speed DVD Maker at Aldi. Of course it was only packaged with Windows software, so I spent some time researching how to get the thing to work on Ubuntu Linux. It turns out that the device is sold under a number of different …

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DV video capture in Ubuntu

Update (2014):

In Ubuntu, DV video-capture over Firewire has basically been broken for normal users for the last 7 years or so. I've been unable to get Kino to work on Ubuntu 10.04 and onward, so I switched to dvgrab. If you run it with root-privileges (sudo dvgrab), it …