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CONTENTS this file
--------------------- "perfect" images, edges -----------------
base01.gif edges in ba01-... : e-NE e-SE e-NW e-nat
base02.gif edges in ba02-... : e-NW e-nat
corner01.gif
--------------- images, edges depending on scale -------------
lines01.gif
small01.gif
small02.gif edges in sm02-... for smallest edge 4 pixels : e-nat
step01.gif
sine01.gif
-------------------- images without edges .. ----------------------
smooth01.gif uniform grey (one value)
smooth02.gif equidistant greyvalues (first-degree)
smooth03.gif second-degree
smooth04.gif third degree, 2nd derivative zero in a ircle of radius 40.
-------------------- noisy images --------------------------------------
Notes:
noise05 pure gaussian noise (128.8, 40.0)
noisexy: a dark square (64x64) on light background
x
0 pure noise, no square
1 - not in use -
2 Gaussian
3 two-valued
4 rectangular (even)
y
1 S/N 10:1 step 40 stddev 4
2 S/N 4:1 step 40 stddev 10
3 S/N 3:1 step 40 stddev 13
4 S/N 2:1 step 40 stddev 20
5 S/N 1:1 step 40 stddev 40
noise05.gif Pure Gaussian noise, std.dev 40, mean 128
noise21.gif Gaussian noise, std.dev 4 , step 40 (10:1)
noise22.gif Gaussian noise, std.dev 10, step 40 (4:1)
noise23.gif Gaussian noise, std.dev 13, step 40 (3:1)
noise24.gif Gaussian noise, std.dev 20, step 40 (2:1)
noise25.gif Gaussian noise, std.dev 40, step 40 (1:1)
edges in noi-... : e-NW e-nat e-natr e-SE