What would be the watermark extraction code for this given embedding code?

clear all; 
close all; clc;
im=imread('cameraman.tif');
image1=im(25:92,75:155);
imshow(image1); title('Original image');% orginal image for watermarking
[ori_row,ori_col]=size(image1)
host_length=ori_row*ori_col;
i=1;
j=1;
k=1;
wmimage=imread('pout.tif');
[wm_row,wm_col] = size(wmimage);
imshow(wmimage); title('Watermark image');
wm=dec2bin(wmimage);
wm_length=wm_row*wm_col*8;
host=dec2bin(image1);
counter=0; 
while i < host_length
        counter=counter+1;
        if counter > wm_length
            break;
        end
        host(i,8)=wm(j,k);
        k=k+1;
        if k>8
            k=1;
            j=j+1;
        end
        i=i+1;
end
    key1=wm_row
    key2=wm_col
im1=bin2dec(host);
im1=reshape(im1,ori_row,ori_col);
image1(1:ori_row,1:ori_col)=im1(1:ori_row,1:ori_col);
display 'After embed';

imshow(image1);title('Watermarked image'); imresize(image1,[256 256]);