How to get a plot value of colour rather than rgb in Histogram plot?

Using the function imhist() we could easily plot rgb profile of a given image, I was just wondering whether there is a y method in MATLAB to access other color plots and information too or not. For example, I want to see yellow color pixel distribution, Is it possible to plot such pixel variations or not.

[shivam sahil]

Hey there! First of thanks a lot for the answer. Further, I wanted to add that after completing my analysis on a particular image I came out with these two results one by the code you mentioned and the other using color cloud, can you please explain what these variations actually mean, I found that pixels are being represented in y-axis and what is this hsv value being represented in y-axis. I have attached my result

. Just wanted to be more clear with the physical significance.

Answer 1

[Image Analyst]

You can use rgb2hsv and look at the histogram of the hue channel

hsvImage = rgb2hsv(rgbImage);
histogram(hsvImage(:,:,1));

You might also like to use the colorcloud() function.

[shivam sahil]

Hey there! First of thanks a lot for the answer. Further, I wanted to add that after completing my analysis on a particular image I came out with these two results one by the code you mentioned and the other using color cloud, can you please explain what these variations actually mean, I found that pixels are being represented in y-axis and what is this hsv value being represented in y-axis. I have attached both my results.

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[Image Analyst]

You only attached one thing - a histogram - not two. If that's the histogram of the hue channel, then you apparently have 5 colors, since you have 5 bars that are non-zero. You have 2 red colors, an orange color, and a yellowish-green color, and a greenish blue color. The vertical height of the bar is the number of pixels with that hue.