MATLAB: How to calculate the area of an input image

areabinaryimageImage Processing Toolbox

I want to calculate the area of the FULL binary image the user inputs is it as simple as heightXwidth if so what function does it

If it is a binary image (so a 2D array), the numel (link) function will do what you want.

It is equivalent to prod(size(BI)), where ‘BI’ is your binary image.

To find the white and black pixels:

numWhitePixels = sum(binaryImage(:));
numBlackPixels = sum(~binaryImage(:));

To get the number of perimeter pixels of the white regions

perimImage = bwperim(binaryImage);
numPerimeterPixels = sum(perimImage(:));

An alternate way to get the area of the white is to use bwarea():

% A weighted sum of white pixels that depends on shape of perimeter.
area = bwarea(binaryImage);

Do you have the original gray scale image, or just this pseudocolored image? If you unfortunately have only the pseudocolored image, see my color segmentation demos in my File Exchange: http://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862