| ::close_edges | Close edge gaps using the edge amplitude image. |
| ::close_edges_length | Close edge gaps using the edge amplitude image. |
| ::derivate_gauss | Convolve an image with derivatives of the Gaussian. |
| ::diff_of_gauss | Approximate the LoG operator (Laplace of Gaussian). |
| ::edges_image | Extract edges using Deriche, Lanser, Shen, or Canny filters. |
| ::edges_sub_pix | Extract sub-pixel precise edges using Deriche, Lanser, Shen, or Canny filters. |
| ::frei_amp | Detect edges (amplitude) using the Frei-Chen operator. |
| ::frei_dir | Detect edges (amplitude and direction) using the Frei-Chen operator. |
| ::highpass_image | Extract high frequency components from an image. |
| ::info_edges | Estimate the width of a filter in ::edges_image. |
| ::kirsch_amp | Detect edges (amplitude) using the Kirsch operator. |
| ::kirsch_dir | Detect edges (amplitude and direction) using the Kirsch operator. |
| ::laplace | Calculate the Laplace operator by using finite differences. |
| ::laplace_of_gauss | LoG-Operator (Laplace of Gaussian). |
| ::prewitt_amp | Detect edges (amplitude) using the Prewitt operator. |
| ::prewitt_dir | Detect edges (amplitude and direction) using the Prewitt operator. |
| ::roberts | Detect edges using the Roberts filter. |
| ::robinson_amp | Detect edges (amplitude) using the Robinson operator. |
| ::robinson_dir | Detect edges (amplitude and direction) using the Robinson operator. |
| ::sobel_amp | Detect edges (amplitude) using the Sobel operator. |
| ::sobel_dir | Detect edges (amplitude and direction) using the Sobel operator. |