MATLAB: Counting Objects and area covered by objects

Question

In the above figure count number for red objects only. Also, calculate the total area covered by all red objects only. Help will be much appreciated

Answer 1

Use the Color Threshold app on the Apps tab of the tool ribbon. Tell it to use HSV color space. Then play around with the sliders to select what you consider to be red.

Also see the color segmentation tutorials in My File Exchange.