MATLAB Answers


Replace the white region in an binary image with Green ? and black colour unaffected

Asked by Anand
on 28 Aug 2014
Latest activity Commented on by Anand
on 29 Aug 2014
I Will read my input image as binary.(may be logical or uint8). The output must be Image with green colours in white region and black remains the same.


Sign in to comment.

2 Answers

Answer by Joseph Cheng
on 28 Aug 2014
Edited by Joseph Cheng
on 28 Aug 2014
 Accepted Answer

you can define the colormap used. here is a quick example
point3d = imread('pears.png');
value = rgb2gray(point3d);
BIN = value>124;
cmap = [ 0 0 0;0 1 0];
so since i have a binary i know the green area is the logical 1 and black 0. if it is not logical then you'll have to scale the colormap to the values of white and black.


I accept your answer.. but I need to store that last output ie Image with green color.. I tried using imwrite(BIN,'new.jpg').. but its only writing the previous black and white image.. any help on this...?
Ah then you'll have to go with Image Analyst's answer.

Sign in to comment.

Answer by Image Analyst
on 28 Aug 2014

Anand, if you want an RGB image instead of a pseudocolored logical image (with values of 0 and 1) then you need to do this:
grayImage = uint8(255 * BIN); % BIN is from Joseph's code.
blackImage = zeros(size(grayImage), 'uint8');
rgbImage = cat(3, blackImage , grayImage, blackImage); % Only green channel is non-zero.
imwrite(rgbImage, fullFileName);

  1 Comment

Sign in to comment.