>>> iatype(iacos)
def iacos(s, t, theta, phi):
"""
- Purpose
Create a cossenoidal image.
- Synopsis
f = iacos(s, t, theta, phi)
- Input
s: Gray-scale (uint8 or uint16) or binary image (logical).
size: [rows cols].
t: Gray-scale (uint8 or uint16) or binary image (logical).
Period: in pixels.
theta: spatial direction of the wave, in radians. 0 is a wave on
the horizontal direction.
phi: Double. Phase
- Output
f: Gray-scale (uint8 or uint16) or binary image (logical).
- Description
Generate a cosenosoid image of size s with amplitude 1, period
T, phase phi and wave direction of theta. The output image is a
double array.
- Examples
#
import Numeric
f = iacos([128,256], 100, Numeric.pi/4, 0)
iashow(ianormalize(f, [0,255]))
"""
from Numeric import cos, sin, pi
cols, rows = s[1], s[0]
x, y = iameshgrid(range(cols),range(rows))
freq = 1./t
fcols = freq * cos(theta)
frows = freq * sin(theta)
f = cos(2*pi*(fcols*x + frows*y) + phi)
return f
