Script for OpenCV installation on Ubuntu 12.10

Installing OpenCV on Ubuntu was painful for me in the past. There are lots of dependencies to be sorted out first and there’s no comprehensive installation tutorial shipped with the OpenCV distribution.
This script has done a great job assembling all necessary “apt-get-install’s” into an executable script. Some personal notes about this:

• It seems to me ” sudo apt-get install libopencv-dev” for dependencies is not necessary – this will be superseded by the subsequent installation of opencv from source. At the end of the scripting installation, the package seems to be in some cache place and be not in effect:
  
• It seems ” sudo apt-get install libavcodec-dev libavformat-dev libswscale-dev” is also unnecessary. These libraries are to be provided by the next fresh installation of ffmpeg follows. Checking their location seems to also confirm my guess:
  
• About version of ffmpeg: ffmepg is under active development as always. The choice of its version is sometimes tricky, especially in running together with OpenCV. I remember the 1.x series was not compatible with OpenCV 2.3 in my previous trial (compilation errors were thrown due to some problem with ffmpeg libraries). The current 2.4.3 version seems to be at least fine with ffmpeg 0.11.2 in compilation.

[Update] From test by Mr. Alok Singh Mahor   (comments below), installing Ubuntu package “libopencv-dev” would already get things work, though the linking order with g++ has to be taken care of as discussed (also comments below and here) . Of course, it’s not bad idea to install from source that always guarantees to bring  in the newest feature of actively developed OpenCV. [Dec 28 2012]

Interface Kinect Depth Camera to Ubuntu Linux

Testing environment: Ubuntu 10.10 64bit

This tutorial on ROS.org provides an excellent walkthrough http://www.ros.org/wiki/kinect/Tutorials/Getting%20Started

Caveats: to launch the visualization at the last step, it seems the configuration file has to be “/tmp/kinect.vcg” exactly. I have changed to other location with the same file name, it turned out not to work, even the launch command has been changed accordingly.

[Update: Feb 25 2011]

Later on I figured out that Openni.org also provides a nice interface package for Kinect on Linux machines. Here are the steps I followed that verified to work (mostly inspired by this post for Windows).

• Download and install the necessary driver from SensorKinect. There are stable (master) and unstable distributions available, and the stable version is recommended (the unstable version doesn’t compile on my Linux even with all dependencies settled). In the unzipped folder, find Platform > Linux-x86 > CreateRedist, and run the script ./RedistMaker. In Platform > Linux-x86 > Redist, run sudo ./install.sh.

• Install the lastest LibUSB.

   sudo apt-get install libusb-1.0-0-dev freeglut3-dev  

• Download and install Openni, PrimeSense Nite, and Primesensor in order.  After downloading from the three links, respectively. One needs to unzip the compressed packages,
  • http://www.openni.org/downloadfiles/openni-binaries/21-stable
  • http://www.openni.org/downloadfiles/openni-compliant-middleware-binaries/34-stable
  • http://www.openni.org/downloadfiles/openni-compliant-hardware-binaries/32-stable

and in each package, install the package by running sudo ./install.(ba)sh.

• Test the demo samples. In OpenNi > Samples > Bin > Release, run ./NiViewer to get realtime scene and depth map viewing.

It’s all about Tex!

A couple of things happened to Tex/Latex recently.

The first one comes about the “Father” of Tex, Prof. Emeritus Donald E. Knuth, gossiping about making an earthshaking announcement in TUG 2010 Conference.  He has actually advertised a nice name for successor of Tex. Guess what? iTex … Hope this gentleman hasn’t turned to an apple fan, provided his character of full of humors.

Record: An Earthshaking announcement by Prof. Knuth

Secondly Texmaker has released its 2.0 version (July 30th, 2010), featuring a built-in previewer. Nowadays there are at least dozens of ways to do previewing in Latex editing, most of which don’t require reopening the viewer. Since I’m accustomed to PdfLatex, several combinations that I have tested and work fine are as below.

1. (Win) Texmaker/Winedt + Sumatra PDF
2. (Linux) Texmaker/Gedit (with Latex plugin) + Evince
3. (Win/Linux) Texworks with built-in previewer
4. (Win/Linux) Texmaker with built-in previewer (New!)
5. (Linux) Eclipse (TeXlipse) + Evince

Sumatra PDF viewer is an excellent lightweight open-source PDF viewer for Windows and should be recommended to all (the catch is it’s a disaster for printing).  Getting down to our business, I have tried to install  Texmaker 2.0 on my Ubuntu laptop (with v1.99 installed) as follows:

$ wget http://www.xm1math.net/texmaker/texmaker_2.0-1_i386.deb
$ sudo apt-get remove texmaker
$ sudo apt-get autoremove
$ sudo dpkg -i texmaker_2.0-1_i386.deb

It is much faster than previous versions and the previewer is really cool! The only catch with the installation is to ensure executing autoremove after removing previous versions (line 2 & 3), otherwise errors will be encountered.  I guess this is because some significant changes have to be made to the underlying engine to facilitate the previewing.

To close with some logistic things: I have changed the theme of this blog to make more place for text, and hopefully this pleases your eyes while reading.

SSH timeout problem in Ubuntu 10.04

Upgrading from previous versions of Ubuntu may result in the problem. Some simple research suggests it may be because SSH client confuses IPv6 with IPv4. So  the workaround is to force the IPv4 search only:

ssh -C  -4 idmsj@xxx.xx.xx.xxx

Btw, my blog received 1,000 hits by yesterday! 🙂

Ubuntu 10.04 Arrives!

Ubuntu 10.04 arrives

http://www.ubuntu.com/products/whatisubuntu/1004features

Count down: Ubuntu 10.04 (LTS)