# Corner detection using Chris Harris & Mike Stephens [duplicate]

I am not able to understand the formula,

What is $W$ (window) and intensity in the formula mean,

I found this formula in opencv doc http://docs.opencv.org/trunk/doc/py_tutorials/py_feature2d/py_features_harris/py_features_harris.html

So $I(x+u,y+v)$ indicates the pixel intensities of all the neighborhood pixels around $(x,y)$. The window function is applied for feature localization. For most often used Gaussian function, the choice of sigma value corresponds to different feature width in the image.