gabor_filter

#!/usr/bin/env python

# Import the modules
import cv2
import sys
import numpy as np

# Set the global parameters

'''
Sigma controls how fat the Gaussian is.
Theta controls the orientation i.e. which direction the filter responses to.
Lambd controls the freqency of the sinusoidal function.
Gamma controls the ellipticity of the Gaussian.
Psi controls the phase shift. (not used here)
'''

# Name of the window
win_name = 'Image'

def update():
    global filter_size, sigma, theta, lambd, gamma, norm_filter
    # Create the fiter banks
    filter = cv2.getGaborKernel(filter_size, sigma, theta, lambd, gamma, ktype=cv2.CV_32F)
    norm_filter = (filter + np.abs(np.min(filter)))/(np.abs(np.max(filter)) + np.abs(np.min(filter)))

# Create the callback functions
def set_k_size(x):
    global filter_size
    filter_size = (x, x)
    update()

def set_sigma(x):
    global sigma
    sigma = x/10.
    update()

def set_theta(x):
    global theta
    theta = x*np.pi/180.0
    update()

def set_lambd(x):
    global lambd
    lambd = x/100.
    update()

def set_gamma(x):
    global gamma
    gamma = x/100.0
    update()

# The main function
if __name__ == '__main__':
    global filter_size, sigma, theta, lambd, gamma, norm_filter
    # Create the trackbars
    # Set the dafault the values
    filter_size = (50, 50)
    sigma = 3
    theta = 0 
    lambd = 10
    gamma = .50

    # Create the window
    cv2.namedWindow(win_name, cv2.WINDOW_NORMAL)

    # Create the trackbars
    cv2.createTrackbar('Filter Size', win_name, 50, 100, set_k_size)
    cv2.createTrackbar('Sigma*10', win_name, 3, 200, set_sigma)
    cv2.createTrackbar('Theta (In degrees)', win_name, 0, 180, set_theta)
    cv2.createTrackbar('Lambda/100', win_name, 10, 10000, set_lambd)
    cv2.createTrackbar('Gamma*100', win_name, 50, 100, set_gamma)

    # Update the filter bank
    update()
    # Create the fiter banks
    filter = cv2.getGaborKernel(filter_size, sigma, theta, lambd, gamma, ktype=cv2.CV_32F)
    
    print "Press ESC to quit the program"
    while(cv2.waitKey(30)!=27):
        cv2.imshow(win_name, norm_filter)