Saturday, April 30, 2011

OpenCV - A Library with Eyes

OpenCV (Open Source Computer Vision Library) is a library of programming functions mainly aimed at real time computer vision, developed by Intel and now supported by Willow Garage. It is free for use under the open source BSD license. The library is cross-platform. It focuses mainly on real-time image processing. The library has more than 2000 optimized algorithms.

History:

OpenCV was started at Intel in 1999 by Gary Bradski for the purposes of accelerating research in and commercial applications of computer vision in the world and, for Intel, creating a demand for ever more powerful computers by such applications. Vadim Pisarevsky joined Gary to manage Intel's Russian software OpenCV team. Over time the OpenCV team moved on to other companies and other Research. Several of the original team eventually ended up working in robotics and found their way to Willow Garage. In 2008, Willow Garage saw the need to rapidly advance robotic perception capabilities in an open way that leverages the entire research and commercial community and began actively supporting OpenCV, with Gary and Vadim once again leading the effort.

OpenCV's application areas include:
  • 2D and 3D feature toolkits
  • Egomotion estimation
  • Facial recognition system
  • Gesture recognition
  • Human–computer interaction (HCI)
  • Mobile robotics
  • Motion understanding
  • Object Identification
  • Segmentation and Recognition
  • Stereopsis Stereo vision: depth perception from 2 cameras
  • Structure from motion (SFM)
  • Motion tracking
To support some of the above areas, OpenCV includes a statistical machine learning library that contains:

  • Boosting
  • Decision tree learning
  • Gradient boosting trees
  • Expectation-maximization algorithm
  • k-nearest neighbor algorithm
  • Naive Bayes classifier
  • Artificial neural networks
  • Random forest
  • Support vector machine (SVM)
( All details extracted from Wikipedia)

References:

OpenCV official page:     http://opencv.org/
OpenCV Documentation:    http://docs.opencv.org/
OpenCV Q&A Forum : http://answers.opencv.org/questions/
OpenCV Developer Zone : http://code.opencv.org/


Community Support

OpenCV Q&A Forum and StackOverFlow.com are the best two places where you can find answers to your problems.

mailing list:    http://tech.groups.yahoo.com/group/OpenCV/
IRC channel:    #opencv
        Core developers of OpenCV won't be present at IRC channels. So it is difficult to find an answer at IRC.
( For those who haven't use IRC before:      visit http://webchat.freenode.net/,     give a nickname you like, enter #opencv in channel field, type the captcha in captcha field, skip all other fields, then click on connect. You will be led to a chat room where you can ask your doubts. Someone may reply)

Recommended Books


"Learning OpenCV: Computer Vision with the OpenCV Library" by Gary Bradski and Adrian Kaehler.
        This is considered to be the best book on OpenCV written by founder of OpenCV himself. Everything is explained in great detail and nice examples, but in C++. Whatever language do you use, whether it is Python,C++ or C, this book is a must read book, if you want to understand OpenCV.
See a look inside the book here:    "Learning OpenCV"