Creating Image stacks and writing GDF file - image

Question

I am attempting to write a function that stack up series of images into image stack and converting it into a gdf file. I don't really know much about GDF files, so please help me out.
X=[];
for i=1:10
if numel(num2str(i))==1
X{i}=imread(strcat('0000',num2str(i),'.tif'));
elseif numel(num2str(i))==2
X{i}=imread(strcat('000',num2str(i),'.tif'));
end
end
myImage=cat(3,X{1:10});
s=write_gdf('stack.gdf',myImage);
Above is to read my images labeled 00001 to 00010, all in grayscale. Everything is fine except in the last line
s=write_gdf('stack.gdf',myImage);
as when I run it, I receive an error:
Data type uint8 not supported
Any help on what this means? Should I convert it to some other colour format?
Thank you in advance!

Answer 1

I would write the code rather like this (I do not have write_gdf function so I can not properly test the code):
NumberOfFiles = 10;
X={}; % preallocate CELL array
for n=1:NumberOfFiles % do not use "i" as your varable because it is imaginary unit in MatLab
FileName = sprintf('%05d.tif',n);
img = imread(FileName); % load image
X{i} = double(img); % and convert to desired format
end
myImage = cat(3,X{1:NumberOfFiles});
s = write_gdf('stack.gdf',myImage);
Keep in mind that
double(img); % and convert to desired format
will not change data range. Your image even in double format will have data range from 0 to 255 if it was in uint8 format on disk. If you need to normalize your data to 0..1 range you should do
X{i} = double(img)/255;
or in more unversal form
X{i} = double(img) / intmax(class(img));