Pixel boundary between black and white regions

**IMAGE_BOUNDARY**,
a MATLAB function which
tries to determine 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_boundary, a MATLAB library which reports the pixels which form the boundary between the black and white regions of a simple image.

IMAGE_CONTRAST, a MATLAB program which applies image processing techniques to increase the contrast in an image.

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

IMAGE_DENOISE, a MATLAB library which applies image processing techniques to remove noise from an image.

IMAGE_DIFFUSE, a MATLAB library which uses diffusion to smooth out an image.

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

IMAGE_EDGE, a MATLAB program which demonstrates a simple technique for edge detection in an image.

IMAGE_MATCH_GENETIC, a MATLAB program which tries to match a 256x256 JPEG image by blending 32 colored rectangles, using ideas from genetic algorithms, based on an example by Nick Berry.

IMAGE_NOISE, a MATLAB library which adds noise to an image.

IMAGE_QUANTIZATION, a MATLAB library 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 library 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.

TRIANGLE, a C program which computes a triangulation of a geometric region, by Jonathan Shewchuk.

- 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.
- timestamp.m, prints the YMDHMS date as a timestamp.

- image_boundary_test.m, calls all the tests.
- image_boundary_test.sh, runs all the tests.
- image_boundary_test.txt, the output file.

- cloud_border.png, the image of the border of the cloud.
- cloud_uh.png
- cloud.png, the image.
- cloud_test.m, applies image_boundary to the data.
- cloud.mat, a MAT file of the boundary pixels.
- cloud.txt, a text file listing the boundary pixels.
- cloud.poly, a poly file of the boundary pixels, for input to Triangle.