image_edge_test

image_edge_test, a MATLAB library which calls image_edge() to demonstrate the detection of edges in an image.

Licensing:

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

Related Data and Programs:

image_edge, a MATLAB library which demonstrates a simple procedure for edge detection in images.

Source Code:

• image_edge_test.m, calls all the tests.
• image_edge_test.sh, runs all the tests.
• image_edge_test.txt, the output file.

COINS is an image of several coins. These are displayed against a uniform gray background, so the edges are easy to spot.

• coins.pgm, a binary PGM file containing a grayscale image of coins.
• coins.ascii.pgm, an ASCII PGM file containing a grayscale image of coins.
• coins.png, a PNG version of the image.
• coins_news1.png, image 1 produced by NEWS shows the input data.
• coins_news2.png, image 2 produced by NEWS shows the data after a 1 pixel boundary has been added.
• coins_news3.png, image 3 shows the E data measuring the "edginess" of each pixel.
• coins_news4.png, image4 uses a threshold. Values below the threshold are set to 0 (black), and values above are set to the maximum (white).
• coins_news5.png, is the same as image 4, but in "reverse video". It is easier to "read" the image with black lines and a white background.
• coins_news6.png, image 6 is actually an RGB color image. It combines the original grayscale image of the coins with the edges marked in red.