RGB Color Space Image Segmentation

Hello All.

I have been trying to replace the original R, G and B components of an RGB image by applying the attached equations in MATLAB.

I don't know the functions to use. I have tried applying different filters but the results I get are inaccurate.

[Image Analyst]

There is nothing attached so we don't know the functions to use either. In the meantime, here's a snippet that might get you started:

% Extract the individual red, green, and blue color channels.
redChannel = rgbImage(:, :, 1);
greenChannel = rgbImage(:, :, 2);
blueChannel = rgbImage(:, :, 3);
% Now do your math on the separate channels, then...
% Recombine separate color channels into a single, true color RGB image.
rgbImage = cat(3, redChannel, greenChannel, blueChannel);

[Muftahu Kabir]

Thank you for the code. Please find attached the equations

[Muftahu Kabir]

I have splitted the image into the three channels. But I don't know the function to use in doing some maths on the channels before using "cat()" to combine all my calculations into a single image

[Image Analyst]

The equations say to set all pixel values to (0,0,0) which is the RGB for pure black. They'll never eve get (255,255,255) because I'' is never anything but (0,0,0) as you can see from equation (5). I think these equations were written down incorrectly. It does not do segmentation when you simply set everything to zero.

[Muftahu Kabir]

Anyone please? Am still yet to resolve it. My main problem is "What function to use in mixing the individual channels using any combination (equation) of my choice".

[Image Analyst]

Everything is zero except I hat if I hat if I'' is more than 0. But from equation (5), I'' is never anything but zero. Hence I hat will never be anything but zero either. I suggest you contact the author for the correct formulas, or look into imgradient().

[Mrutyunjaya Hiremath]

There is a problem in given equations

Here is the reults, after some assumptions for intitial values, like Idash ... sigma ...

[Muftahu Kabir]

@Mrutyunjaya Hiremath

Interesting.... After using which of the equations did you arrive at your result? I have been trying to get a similar result to yours using equation (4) but I couldn't. Can you please share the code you used?

Answer 1

[Mrutyunjaya Hiremath]

Hello Muftahu Kabir,

Here is the code ...

clear all;
close all;
clc;

I = imread('1.jpg');
figure, imshow(I);

IR = I(:,:,1);
IG = I(:,:,2);
IB = I(:,:,3);

I4 = I;
I41Index = find((IG - ((IR+IB)/2) + 15) > 0);
I4(I41Index) = 0;
I42Index = find((IR - IB) > 20);
I4(I42Index) = 0;
I43Index = find((IG - IR) > 15);
I4(I43Index) = 0;
figure, imshow(I4);

I5 = I4;
delta = 50;
I51Index = find(I4 > (255 - delta));
I5(I51Index) = 0;
I52Index = find(I4 < delta);
I5(I52Index) = 0;
figure, imshow(I5);

I6 = I5;
I61Index = find(I5 > 0);
I6(I61Index) = 255;
I62Index = find(I5 == 0);
I6(I62Index) = 0;
figure, imshow(I6);
imwrite(I6, 'I6.jpg');

[Muftahu Kabir]

Hello Mrutyunjaya Hiremath,

I truly appreciate your contribution.

It has gone a long way assisting me in doing my research. Thank you so much