How Imfuse works? what is the difference between green and magenta?

I used imfused [ C1=imfuse(I1,I2,'falsecolor','ColorChannels',[2 1 2]); ]. The result is an image with gray, magenta and green colors.

Reading matlab documentation, "Gray regions in the composite image show where the two images have the same intensities. Magenta and green regions show where the intensities are different."

Question; What is the difference between gray and magenta here? why matlab colors them differently?

Another question, can someone brefly explains how imfuse works? or any link that I can educate myself?

Thanks a million

Answer 1

[Shaunak]

Hi,

I find that you used ‘imfuse’ in MATLAB with the 'falsecolor' method to visually compare two grayscale images using color-coded overlays.

When using this syntax:

C1 = imfuse(I1, I2, 'falsecolor', 'ColorChannels', [2 1 2]);

you're mapping one image to the green channel and the other to magenta (a combination of red and blue).

Here's the difference:

• Gray regions in the result indicate where both images have similar intensities at the same location — meaning the green and magenta components mix equally to produce gray.
• Magenta regions show where only I1 (in this mapping) has strong intensity — i.e., the first image has more detail than the second at that location.
• Green regions show where only I2 is strong.

This colour coding helps to visually identify differences between the two images.

For more in-depth understanding of ‘imfuse’ and false-color visualization, kindly refer to the following MathWorks documentation:

🔹 https://www.mathworks.com/help/images/ref/imfuse.html

You can also refer to the following MathWorks documentation to learn more about how Intensity based Image Registration works:

🔹 https://www.mathworks.com/help/images/intensity-based-automatic-image-registration.html

Hope this helps!