In [1]:

    

import numpy as np
import matplotlib.pyplot as plt
from scipy.sparse import diags
from scipy.sparse import vstack
from scipy.sparse.linalg import lsqr

from image_io import *
from get_mask import *
from align_images import *


    

In [2]:

    

# Load images
fpath = './images/'
s_fname = 'lego.jpg'
t_fname = 'landscape.jpg'
s = image_open(fpath, s_fname)
t = image_open(fpath, t_fname)


    

In [3]:

    

s, s_mask, tinyt, tinyt_topleft = align_images(s, t)


    

In [4]:

    

def shift(m, direction):
    padded = np.pad(m, [(d, 0) if d>0 else (0, -d) for d in direction], mode='constant')
    return padded[[np.s_[:sh] if d>0 else np.s_[-sh:] for sh, d in zip(m.shape, direction)]]
def inside(mask):
    return shift(mask, (-1, 0)) & shift(mask, (0, -1)) & shift(mask, (1, 0)) & shift(mask, (0, 1))


    

In [5]:

    

s_inside = inside(s_mask)
s_border = s_mask & ~s_inside
s_outside = ~s_inside


    

In [6]:

    

def construct_A4(s, s_border=[[]]):
    imh, imw = s.shape
    sy, sx = np.where(s_border)
    npx = imh*imw
                 # [x,x+1], [x,x-1], [y,y+1], [y,y-1]
    all_offsets = [[0, -1], [0, 1], [0, -imw], [0, imw]]
    As = []
    for offset in all_offsets:
        A = diags(
            diagonals=[1, -1],
            offsets=offset,
            shape=[npx, npx],
            format='csr',
            dtype=float)
        r, c = (A[imw*sy + sx, :] < 0).nonzero()
        A[(imw*sy + sx)[r], c] = 0
        r, c = A[imw*sy + sx, :].nonzero()
        As.append(A)
    return vstack(As)


    

In [69]:

    

def set_b(b, mask, values):
    bigmask = np.concatenate([mask, mask, mask, mask])
    b[bigmask] = values[bigmask]
    return b


    

In [83]:

    

A4 = construct_A4(s)
t_prime = A4.dot(tinyt.ravel())
s_prime = A4.dot(s.ravel())

max_prime = np.maximum(s_prime, t_prime)

b = t_prime.copy()
b = set_b(b, s_inside.ravel(), max_prime)
tinyt_values = np.concatenate([tinyt.ravel(), tinyt.ravel(), tinyt.ravel(), tinyt.ravel()])
b = set_b(b, s_border.ravel(), tinyt_values)

A4 = construct_A4(s, s_border=s_border)


    

In [84]:

    

imh, imw = s.shape
v = lsqr(A4, b)[0]
out = v.reshape((imh, imw))


    

In [85]:

    

plt.imshow(out, cmap='gray', vmin=0, vmax=1)
plt.show()


    

In [82]:

    

tttly, tttlx = tinyt_topleft
tty, ttx = tinyt.shape
t[tttly:tttly + tty, tttlx:tttlx + ttx] = out
#plt.imshow(t, cmap='gray', vmin=0, vmax=1)
#plt.show()
image_save('./output/','soAWESOME.jpg', t)


    

In [40]:

    




    

In [13]:

    




    

In [ ]: