fix problem with addPoissonNoise

addPoissonNoise now correctly handles input that is not "double"

functions/generators/addPoissonNoise.m

@@ -58,8 +58,15 @@ if nargin < 2
     photonsPerPixel = 10000;
 end
 
+imNoisy = zeros(size(im), 'like', im);
+
+% imnoise needs double as input
+if ~isa(im, 'double')
+  im = double(im);
+end
+
 poissonFactor = 1e-12*photonsPerPixel;
-imNoisy = (1./poissonFactor) * imnoise(poissonFactor * im,'poisson');
+imNoisy(:) = (1./poissonFactor) * imnoise(poissonFactor * im,'poisson');
 
 end