Removing overlapping pixels in black and white images

I have two black and white images, let say A and B, I would like to remove overlapped pixel between image A and B and maintain the pixels from image A only after removing the overlapped pixels? How can I do this?

As shown in the following image, I would like to remove the green and black part and keep the pink part of the image.

Answer 1

[KSSV]

I = imread('image.jpeg') ; 
R = I(:,:,1) ; 
G = I(:,:,2) ; 
B = I(:,:,3) ; 

% Get black region 
I1 = rgb2gray(I) ; 
idx = I1 < 50 ;

R(idx) = 255 ;
G(idx) = 255 ;
B(idx) = 255 ;
% remove green part
idx = G<=255 ;
R(idx) = 255 ;
B(idx) = 255 ;
% Remove Black 
I2 = cat(3,R,G,B) ;
imshow(I2)

There could be more elegant solution.