Open Modis images in a loop and apply NDVI on them

Hello,

I have a 12 modis images that I want to open in a loop. and I just don't know how, I want only to work on their first and second bands ( as it is mentioned in the picture )

Also I tried to apply NDVI and I dont know why It doesn't work ( picture 2)

Answer 1

[Kevin Chng]

Hi

first of all, load your information into array first, which allow you to use indexing to get their information later.

folder='E:\Matlab';
filetype='*.hdf'; 
f=fullfile(folder,filetype);
d=dir(f);
for i=1:numel(d);
  Red(i) = hdfread(fullfile(folder,d(i).name), 'MORIS_Grid_500m_2D','Fields','sur_ref1_b01_1');
  NIR(i) = hdfread(fullfile(folder,d(i).name), 'MORIS_Grid_500m_2D','Fields','sur_ref1_b02_1');
end

After the code above, now we use indexing to get the information from the array for our calculation.

    for i=1:1:numel(d)
        NDVI(i) = double(NIR(i)-Red(i)) ./ (double (NIR(i) + Red(i)));
    end

Kindly accept my answe if they are working for you.