Feature Detection Functions

This section describes feature detection functions.

The set of the Sobel derivative filters is generally used to find edges, ridges, and blobs, especially in case of scale-space images, for example, pyramids.

The following naming conventions are used in the equations described below:

D_x and D_y are the first x and y derivatives, respectively.
D_xx are D_yy are the second x and y derivatives, respectively.
D_xy is the partial x and y derivative.
D_xxx and D_yyy are the third x and y derivatives, respectively.
D_xxy and D_xyy are the third partial x and y derivatives.