**image_boundary**,
a MATLAB code which
determines the pixels that lie on the boundary between the
black and white portions of a simple image. The image should only
involve two regions, one entirely black and one entirely white.

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

**image_boundary** is available in
a MATLAB version.

image_contrast, a MATLAB code which applies image processing techniques to increase the contrast in an image.

image_decimate, a MATLAB code which compresses an image by dropping the even rows and columns of data.

image_denoise, a MATLAB code which applies image processing techniques to remove noise from an image.

image_diffuse, a MATLAB code which uses diffusion to smooth out an image.

image_double, a MATLAB code which doubles the height and width of an image by repeating each row and column.

image_edge, a MATLAB code which demonstrates a simple technique for edge detection in an image.

image_noise, a MATLAB code which adds noise to an image.

image_quantization, a MATLAB code which demonstrates how the KMEANS algorithm can be used to reduce the number of colors or shades of gray in an image.

image_rgb_to_gray, a MATLAB function which creates a grayscale version of an RGB image.

image_threshold, a MATLAB code which makes a black and white version of a grayscale image by setting all pixels below or above a threshold value to black or white.

poly, a data directory which contains examples of POLY files, a 2D format used by triangle and showme, for Planar Straight Line Graphs.

- boundary_to_poly.m, writes a poly file containing the boundary information.
- i4mat_write.m, writes an I4MAT to a file.
- image_boundary.m, sets pixels less than or equal to A to black, and pixels greater than A to white.