main.py

#!/usr/bin/env python3

from PIL import Image
from roipoly import RoiPoly

import numpy as np
import matplotlib.pyplot as plt

from skimage.transform import rescale, resize

def main():

    # Read source image :
    source = np.array(Image.open('Pictures/orca.jpg'))
    nb_row_s,nb_col_s,nb_ch_s = source.shape

    s = plt.figure()
    plt.imshow(source)
    plt.axis('off')

    # Select and display polygon in source picture
    poly = RoiPoly(color='r')
    source_1c = source[:,:,0]
    polygonMask = poly.get_mask(source_1c)

    x_poly = np.around(poly.x)
    y_poly = np.around(poly.y)

    # Bounding rectangle of poly
    i_p_min = int(min(y_poly))
    i_p_max = int(max(y_poly))
    j_p_min = int(min(x_poly))
    j_p_max = int(max(x_poly))

    # Read target image :
    target = np.array(Image.open('Pictures/mountains.jpg'))
    nb_row_t,nb_col_t,nb_ch_t = target.shape

    t = plt.figure()
    plt.imshow(target)
    plt.axis('off')

    # Select rectangle r in target
    print('Select opposite corners of the target zone');
    [p1,p2] = plt.ginput(2);
    j_r_min = int(max(min(p1[0], p2[0]), 0))
    j_r_max = int(min(max(p1[0], p2[0]), nb_col_t))
    i_r_min = int(max(min(p1[1], p2[1]), 0))
    i_r_max = int(min(max(p1[1], p2[1]), nb_row_t))

    plt.plot([j_r_min, j_r_min], [i_r_min, i_r_max], color='red')
    plt.plot([j_r_min, j_r_max], [i_r_min, i_r_min], color='red')
    plt.plot([j_r_max, j_r_max], [i_r_min, i_r_max], color='red')
    plt.plot([j_r_min, j_r_max], [i_r_max, i_r_max], color='red')
    plt.draw()

    # Target sub-matrix corresponding to the rectangle r :
    r = target[i_r_min:i_r_max,j_r_min:j_r_max,:]

    # Select the sub-matrices in the bounding box of the polygon :
    source = source[i_p_min:i_p_max,j_p_min:j_p_max,:];
    polygonMask = polygonMask[i_p_min:i_p_max,j_p_min:j_p_max];

    # Resize s and p :
    nb_row_r,nb_col_r,nb_ch_r = r.shape
    source = resize(source, r.shape, anti_aliasing=True, mode='constant')
    polygonMask = resize(polygonMask, r.shape, anti_aliasing=True, mode='constant')

    plt.show()

if __name__ == '__main__':
    main()