change white to gray in an image

I have this image and I want to turn all the white pixels to gray, but I don´t know how to do it, can somebody help me?.

thakns in advance

Answer 1

[Ameer Hamza]

Try this

im = imread('image.png');
im_gray = rgb2gray(im);
mask = imbinarize(im_gray);
im(mask(:,:,[1 1 1])) = 255*0.8; % 255*0 is black and 255*1 is white, any other value between is shade of gray
imshow(im);