Installing OpenCV 2.3.1 with TBB enabled in Windows

(To install OpenCV on Ubuntu refer to this post).
In the last post, I explained how to install OpenCV without any third party libraries. In this one I will explain how to install OpenCV with Intel TBB. For those of you who don't know about TBB, it stands for Threaded Building Blocks. It is a library which greatly simplies creating threaded applications on Intel platform.  Without TBB installed your OpenCV algorithms run only on single core. When OpenCV is installed with TBB, the library automatically uses threading to utilize all the cores available to your processor and hence you get a significant improvement in the speed.

Installing OpenCV 2.3.1 on Windows 7

(To install OpenCV on Ubuntu refer to this post).
Installing OpenCV can be tricky on Windows. If you are using 32 bit version of Windows then you are in luck. You will find 32-bit executables ready for deployment. But if you happen to use a 64 bit version of Windows you will need to build the binaries yourself.
Note: This guide does not cover installing third party libraries. (Refer to this post to install OpenCV on windows with Intel TBB support)

You will need the following softwares:

Installing OpenMPI on Ubuntu 12.04

Installing OpenMPI
Although the instructions are tested on 12.04 but they should work for other flavours of linux. Building Open MPI is typically a combination of running "configure" and "make".

Step 1: Downloading OpenMPI
Download the latest version of OpenMPI from here.

Step 2: Extracting OpenMPI source
Untar and unzip the download file.