how to threshold a color image?

how to threshold a color image? How to set threshold value for a color image?

[Walter Roberson]

Under what conditions should the color image be deemed to be above the threshold ?

[Sivakumaran Chandrasekaran]

by selecting any pixel values .. such as threshold=100 etc.,

[Walter Roberson]

It is not possible to express color by a single linear value. One could threshold on each color channel, but the result is not likely to be useful.

Answer 1

[Image Analyst]

Try Brett's nice interactive tool : http://www.mathworks.com/matlabcentral/fileexchange/38484-segmenttool-an-interactive-gui-for-segmenting-images