Some helpful OpenCV framework functionality-based extensions. It does include:

• SUSAN edge/corner detector with pre-filtering mechanism, that is described here: https://users.fmrib.ox.ac.uk/~steve/susan/susan/susan.html;
• Image illumination normalization method that is provided by X. Tan and B. Triggs in their "Enhanced Local Texture Feature Sets for Face Recognition Under Difficult Lighting Conditions";
• Other supplementary functions.

Tips: OpenCV should have an Environment Variable named OPENCV_DIR which should reference to opencv library root (That means this: [your/opencv/root]/opencv-x.x.x, where x.x.x - is for opencv particular version for the case if you have multiple ones).