ContrastEnhancement.m

% ContrastEnhancement - This attempts to increase contrast by removing noise as proposed by Michel et al. This starts with subtracting off a highly smoothed version of imageIn followed by median filter.
%    imageOut = ImProc.ContrastEnhancement(imageIn,sigma,MedianNeighborhood);
%    	ImageIn -- can be an image up to three dimensions and of type (uint8,int8,uint16,int16,uint32,int32,single,double).
%    	Sigma -- these values will create a n-dimensional Gaussian kernel to get a smoothed image that will be subtracted of the original.
%    		N is the number of dimensions of imageIn
%    		The larger the sigma the more object preserving the high pass filter will be (e.g. sigma > 35)
%    	MedianNeighborhood -- this is the neighborhood size in each dimension that will be evaluated for the median neighborhood filter.
%    	ImageOut -- will have the same dimensions and type as imageIn.
function imageOut = ContrastEnhancement(imageIn,sigma,MedianNeighborhood)
    % check for Cuda capable devices
    curPath = which('ImProc.Cuda');
    curPath = fileparts(curPath);
    devStats = ImProc.Cuda.DeviceStats();
	n = length(devStats);

    % if there are devices find the availble one and grab the mutex
    if (n>0)
       foundDevice = false;
       device = -1;
       
       while(~foundDevice)
        for deviceIdx=1:n
            mutexfile = fullfile(curPath,sprintf('device%02d.txt',deviceIdx));
            if (~exist(mutexfile,'file'))
                try
                       fclose(fopen(mutexfile,'wt'));
                catch errMsg
                       continue;
                end
                foundDevice = true;
				f = fopen(mutexfile,'at');
				fprintf(f,'%s',devStats(deviceIdx).name);
				fclose(f);
                device = deviceIdx;
                break;
            end
        end
        if (~foundDevice)
            pause(2);
        end
       end
       
       try
            imageOut = ImProc.Cuda.ContrastEnhancement(imageIn,sigma,MedianNeighborhood,device);
        catch errMsg
        	delete(mutexfile);
        	throw(errMsg);
        end
        
        delete(mutexfile);
    else
        imageOut = lclContrastEnhancement(imageIn,sigma,MedianNeighborhood);
    end
end

function imageOut = lclContrastEnhancement(imageIn,sigma,MedianNeighborhood)

end