# -*- coding: utf-8 -*-
import matplotlib.pyplot as plt
import numpy as np




#import image
imCol = plt.imread("mini.jpg", format=None)
imNb = 1/3 * imCol[:,:,0]+  1/3 * imCol[:,:,1] + 1/3 * imCol[:,:,2];

#R

# compress
iterationsGlobales = 5 
iterations = 20

imComp = imNb
FF= [[]]*len(imComp[:,0])
GG= [[]]*len(imComp[0,:])

for x in range(iterationsGlobales):
    F=np.ones((len(imComp[:,0]), 1))
    G=np.ones((len(imComp[0,:]), 1))
    for y in range(iterations):
        F = np.dot(imComp, G)               / np.dot(np.transpose(G), G)
        G = np.dot(np.transpose(imComp), F) / np.dot(np.transpose(F), F)
    FF = np.append(FF, F, 1)
    GG = np.append(GG, G, 1)
    
    
    
    imComp = imComp - np.dot(F,np.transpose(G))
    

imRecons = np.dot(FF,np.transpose(GG))
#imRecons = np.dot(FF[:,None],GG[None,:])

plt.figure(dpi=1200)


plt.subplot(1, 3, 1)
plt.axis('off')

plt.title("Image importée", fontdict=None, loc='center', pad=None)
plt.imshow(imNb, interpolation = "nearest", cmap = 'gray')


plt.subplot(1, 3, 2)
plt.axis('off')
plt.title("Erreur", fontdict=None, loc='center', pad=None)
plt.imshow(np.dot(F,np.transpose(G)), interpolation = "nearest", cmap = 'gray')


plt.subplot(1, 3, 3)
plt.axis('off')
plt.title("Image compressée", fontdict=None, loc='center', pad=None)
plt.imshow(imRecons, interpolation = "nearest", cmap = 'gray')
plt.show()