How to access a set of images as a file for character recognition?

I'm doing character recognition. Now I have a database of handwritten English alphabets. 55 samples of each letter(in .png format) is stored in a folder. There are 26 such folders. Got a code which reads the samples from a file as :

fid=fopen('data0','r');
for i=1:300
[t0,N]=fread(fid,[28 28],'uchar');
t00(:,i)=(reshape(t0,1,784)');
end;

This loop reads data from a file 'data0' which is in some other format and has 300 samples of the digit 0. I have to replace 'data0' by the folder of samples any one alphabet. Is there any method to convert the folder into a suitable format? or is there any database in a suitable format available?

Answer 1

[Walter Roberson]

http://matlab.wikia.com/wiki/FAQ#How_can_I_process_a_sequence_of_files.3F