Discover MakerZone

MATLAB and Simulink resources for Arduino, LEGO, and Raspberry Pi

Learn more

Discover what MATLAB® can do for your career.

Opportunities for recent engineering grads.

Apply Today

New to MATLAB?

How to set background as black without appearing in colorbar?

Asked by Shing

Shing (view profile)

on 29 Mar 2013

Hi, I have an image and the pixel values range from 0 to 180, represented by jet colorbar range.

However, I would like to differentiate my object in the image with its background by setting the background pixels out of the [0 180] range, such as 500, and make the pixels which have 500 value to be black.

But I do not want it to appear as part of the color bar. How can I go about doing that ??

Any form of help is much appreciated and happy holiday! :)

0 Comments

Shing

Shing (view profile)

Products

No products are associated with this question.

2 Answers

Answer by Doug Hull

Doug Hull (view profile)

on 29 Mar 2013

Axes have color. You could set the color of the axes. Then you can put NaN in the image on any pixel you want to be 'empty'.

1 Comment

Shing

Shing (view profile)

on 30 Mar 2013

Hi,

I tried setting NaN into my image matrice. But how do I go about setting it as black background without it appearing within color bar?

Doug Hull

Doug Hull (view profile)

Answer by Sean de Wolski

Sean de Wolski (view profile)

on 29 Mar 2013

Set the 'YLim' property of the colorbar to be the range you want:

surf(peaks);
h = colorbar;
set(h,'YLim',[2 5]);

0 Comments

Sean de Wolski

Sean de Wolski (view profile)

Contact us