| convol_image | Convolve an image with an arbitrary filter mask. |
| expand_domain_gray | Expand the domain of an image and set the gray values in the expanded domain. |
| gray_inside | Calculate the lowest possible gray value on an arbitrary path to the image border for each point in the image. |
| gray_skeleton | Thinning of gray value images. |
| lut_trans | Transform an image with a gray-value look-up-table |
| principal_comp | Compute the principal components of multi-channel images. |
| symmetry | Symmentry of gray values along a row. |
| topographic_sketch | Compute the topographic primal sketch of an image. |