As part of your OpenCV setup, you probably have a directory called haarcascades. It contains cascades that are trained for certain subjects using tools that come with OpenCV. The directory's full path depends on your system and method of setting up OpenCV, as follows:
- Build from source archive:
<unzip_destination>/data/haarcascades - Windows with self-extracting ZIP:
<unzip_destination>/data/haarcascades - Mac with MacPorts:
/opt/local/share/OpenCV/haarcascades - Mac with Homebrew: The
haarcascadesfile is not included; to get it, download the source archive - Ubuntu with apt or Software Center: The
haarcascadesfile is not included; to get it, download the source archive
Tip
If you cannot find haarcascades, then download the source archive from http://sourceforge.net/projects/opencvlibrary/files/opencv-unix/2.4.3/OpenCV-2.4.3.tar.bz2/download (or the Windows self-extracting ZIP from http://sourceforge.net/projects/opencvlibrary/files/opencv-win/2.4.3/OpenCV-2.4.3.exe/download), unzip it, and look for <unzip_destination>/data/haarcascades.
Once you find haarcascades, create a directory called cascades in the same folder as cameo.py and copy the following files from haarcascades into cascades:
haarcascade_frontalface_alt.xml haarcascade_eye.xml haarcascade_mcs_nose.xml haarcascade_mcs_mouth.xml
As their names suggest, these cascades are for tracking faces, eyes, noses, and mouths. They require a frontal, upright view of the subject. We will use them later when building a high-level tracker. If you are curious about how these data sets are generated, refer to Appendix B, Generating Haar Cascades for Custom Targets. With a lot of patience and a powerful computer, you can make your own cascades, trained for various types of objects.