image_decimate, a MATLAB code which "decimates" an image by removing the even rows and columns, resulting in a file that is about 1/4 the size of the original.

Modifying an image in this way is a very crude method of compression. However, it does suggest how much redundant information exists in a typical image file.


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


image_decimate is available in a MATLAB version.

Related Data and Programs:

image_boundary, a MATLAB code which reports the pixels which form the boundary between the black and white regions of a simple image.

image_components, a MATLAB code which seeks the connected "nonzero" or "nonblack" components of an image or integer vector, array or 3D block.

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


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 procedure for edge detection in images.

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 code which makes 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.

Source Code:

Last revised on 03 February 2019.