how to convert output to integer?

hi i wrote the following code for converting image to textfile but the arrays of output are hexadecimal in the textfile.how could I convert them to integer??? tnx

a= imread('D:\IP1\12.jpg');
I=rgb2gray(a);
% iD conversion
b = I(:);
% New txt file creation
fid = fopen('D:\IP1\in2.txt');
% Hex value write to the txt file
fprintf(fid, '%x\n', b);
% Close the txt file
fclose(fid)

Answer 1

[James Tursa]

Use %d instead of %x for the output format.

[fahim GH]

thanks for answering,i have this error now

Error using fprintf Invalid file identifier. Use fopen to generate a valid file identifier.

Error in imgtotxt (line 8) fprintf(fid, '%d\n', b);

[Walter Roberson]

[fid, message] = fopen('D:\IP1\in2.txt', 'wt');
if fid < 0
  error('Failed to open because: %s', message);
end