iflat.py

#!/usr/bin/python2

import cv2
import numpy as np
import Tkinter
import tkMessageBox
from tkFileDialog import askopenfilename

HELP = """
This script have been made to counter brightness irregularity
Select calibration image (blank image)
and target image

Both images must have been taken under the exact same light

(see example in test folder)

result will saved under result.png
"""

def limit(x, mini, maxi):
    if (x < mini):
        x = mini
    elif (x > maxi):
        x = maxi
    elif (x != x):
        x = 0
    return (x)

def iflat(img, calib):
    calib = cv2.GaussianBlur(calib, (7,7), 0)
    av = np.average(calib)
    height, width = calib.shape
    for col in range(width):
        for row in range(height):
            coef = calib.item(row, col) / av
            if (coef == 0):
                coef = 1
            pix = img.item(row, col) / coef
            pix = limit(pix, 0, 255)
            img.itemset(row, col, pix)
    return (img)

class TkApp(Tkinter.Tk):
    def __init__(self, parent):
        Tkinter.Tk.__init__(self, parent)
        self.calib_file = ""
        self.target_file = ""
        self.parent = parent
        label = Tkinter.Label(self, text=HELP)
        label.pack(side=Tkinter.TOP)
        b1 = Tkinter.Button(self, text="Select calib image", command=self.select_calib)
        b1.pack(side=Tkinter.LEFT)
        b2 = Tkinter.Button(self, text="Select target image", command=self.select_target)
        b2.pack(side=Tkinter.RIGHT)
        b3 = Tkinter.Button(self, text="Launch", command=self.launch)
        b3.pack(side=Tkinter.BOTTOM)
    
    def select_calib(self):
        self.calib_file = askopenfilename()
    
    def select_target(self):
        self.target_file = askopenfilename()
    
    def launch(self):
        if (not self.calib_file or not self.calib_file):
            tkMessageBox.showerror("Error", "Select target and calibration image")
            return
        self.quit()
        calib = cv2.imread(self.calib_file, cv2.CV_LOAD_IMAGE_GRAYSCALE)
        img = cv2.imread(self.target_file, cv2.CV_LOAD_IMAGE_GRAYSCALE)
        if (img.size != calib.size):
            tkMessageBox.showerror("Error", "Both images must be same size")
        result = iflat(img, calib)
        cv2.namedWindow('image',cv2.WINDOW_NORMAL)
        cv2.resizeWindow('image', 800, 800)
        cv2.imshow("image", result)
        cv2.imwrite("result.png", result);
        cv2.waitKey(0)

def main():
    app = TkApp(None)
    app.title("iflat script")
    app.geometry("400x200")
    app.mainloop()
    '''
    calib = cv2.imread("test/flat.bmp",
                        cv2.CV_LOAD_IMAGE_GRAYSCALE)
    img = cv2.imread("test/usaf.bmp",
                        cv2.CV_LOAD_IMAGE_GRAYSCALE)
    result = iflat(img, calib)
    cv2.namedWindow('image',cv2.WINDOW_NORMAL)
    cv2.resizeWindow('image', 800, 800)
    cv2.imshow("image", result)
    cv2.imwrite("result.png", result);
    cv2.waitKey(0)
    '''


if (__name__=="__main__"):
    main()