How write binary image pixel values to a text file such that each row contains only one pixel value of 8bit?

I am trying to read txt file using $readmemb in verilog , for this I need binary pixel values for one pixel in each row.

for e.g.

11010100

01011001

00101011

..... and so on

When I try writing to a txt file in matlab it fills all the display .How to do it?

clear all;

close all;

I_in=imread('C:\Users\ASUS\Documents\MATLAB\work\Mona_Lisa.jpg'); // I_in is a 256x256x3 image .

B = dec2bin(I_in); // B is a 196608 x 8 char matrix

fprintf(B);

Id2=fopen('img3.txt','wt');

fprintf(Id2,B);

fclose(Id2);

Answer 1

[DGM]

I'm no wizard with fprintf(), but this is one way to deal with it.

I_in=imread('peppers.png');
B = cellstr(dec2bin(I_in,8)); % make sure that the words are 8 char wide

fprintf('%s\n',B{1:5}) % display a sample of what's written to the file

00111110
00111111
01000001
00111111
00111111

% write to the file
Id2=fopen('img3.txt','wt');
fprintf(Id2,'%s\n',B{:});
fclose(Id2);

Alternatively, you could avoid the use of the cell array (might be faster)

I_in=imread('peppers.png');
B = dec2bin(I_in,8);

fprintf([repmat('%c',[1 8]) '\n'],B(1:5,:).')

00111110
00111111
01000001
00111111
00111111

% write to the file
Id2=fopen('img3.txt','wt');
fprintf(Id2,[repmat('%c',[1 8]) '\n'],B.');
fclose(Id2);

[vidya nand]

Just to verify that all the pixels are right , could you please give the code to reconstruct the same image from the text file?

[DGM]

fname = 'img3.txt';
nbits = 8;

I_in = imread('peppers.png');
s = size(I_in);
B = dec2bin(I_in,nbits);

% write to the file
Id2 = fopen(fname,'wt');
fprintf(Id2,[repmat('%c',[1 nbits]) '\n'],B.');
fclose(Id2);

% read the file
Id2 = fopen(fname,'r');
A = fscanf(Id2,'%s');
fclose(Id2);

A = reshape(A,nbits,[]).';
I_out = uint8(bin2dec(A));
I_out = reshape(I_out,s);

imshow(I_out)

Note that it's necessary to know the size of the image in order to reconstruct it. Without this information, guesses can be made by finding the factors of the vector length and making some reasoned assumptions about practical aspect ratio and the channel arrangements.

[vidya nand]

thanks a lot