how to make a colorwheel in matlab?

Hello

I want to make a ColorWheel in matlab, sorry for asking simple question. I am not fluent in matlab and I don't know how we can make a colorwheel in matlab. Whould you please indicate me?

[John D'Errico]

You should read this:

http://www.mathworks.com/matlabcentral/answers/6200-tutorial-how-to-ask-a-question-on-answers-and-get-a-fast-answer

Not being fluent is not a problem. But you need to make some effort.

[Maryam]

yes!but i did not find the answer

Answer 1

[Image Analyst]

See my attached demo, below the image. It makes a number of figures, including the one below.

If you want to mask it so that it's circular, create a circular mask like in the FAQ

Other color demos are in my File Exchange including one to synthesize an X-rite Color Checker Chart.

[Maryam]

Many thanks for your reply in advance, I want to display a page to my subjects in psychtoolbox,this page must have a static wheel which show them hue(by degree between 0to360)and saturation(changing 0to100), and also a bar witch is consist of brightness(0to100). I want to have a patch(dynamic patch)above to this page.Each tome that subjets click on wheel and bar color of this patch must change and show his percept color.I mean i want to show static whell for heu and saturation and bar for brightness and dynamic patch for showing all perceptive color. Would you please help me for writing the code?result must be something like we can see in photoshope. Many thanks

[Image Analyst]

I don't understand what you said. What's wrong with what I've provided above? I have attached another demo for color wheel. If that's not what you want either, then please try to get another English speaker to proofread what you wrote, because it does not make sense to me. I don't know what a dynamic patch is. I don't understand at all what this sentence means: "Each tome that subjets click on wheel and bar color of this patch must change and show his percept color.I mean i want to show static whell for heu and saturation and bar for brightness and dynamic patch for showing all perceptive color."

You can use ginput() to have the user click on a point in an image. That's about all I can think of to say after reading that.

Answer 2

[David Young]

The functions you need are meshgrid, atan2 and hsv2rgb. Possibly also hypot if you want to make the centre bright or dark.