How to create .pgm image from text file?

Hello

I have a .txt file in the following format(see attached file):

line 1: integer height

line 2: integer width

line 3: float ratio

line 4: int size

line 5: int start

line 6: int goal

The next lines from 7 to height must be stored in a matrix height*width

The matrix is matrix of integers ( 0s and 100s)

The 0s must be converted to white pixels(free spaces) while 100s must be converted to black pixels(obstacles), so the image is a map that can be used in robot navigations.

How can I read this file and convert the matrix into .pgm image file.

Thanks a lot in advance,

[Eman Almoaili]

It works. Now I have .pgm image from the matrix in the tex file. I cannot attach the .pgm file here as it is not supported. However, the image is very small. How can I create the image so that each pixel can be seen clearly?

In fact, the image is a 2d grid generated as a map for robotics applications, the width and height can be 8,16, 32, .. up to 256. Thus, I need a clear image.

% read the text file and store variables
fid = fopen('map2.txt','r');
lines = textscan(fid,'%s','delimiter','\n');
fclose(fid);
lines = lines{1};
height = sscanf(lines{1},'%d'); 
width = sscanf(lines{2},'%d');
Ratio = sscanf(lines{3},'%f');
Size = sscanf(lines{4},'%d');
start = sscanf(lines{5},'%d');
goal = sscanf(lines{6},'%d');
% parse lines 7-height, so M is a martix height*width
M = zeros(height,width);
for i = 1:height
  M(i,:) = sscanf(lines{6+i},'%d')';
end
% Text to image conversion
% Create a matrix of the desired image dimensions
% In this case, height and width
p = zeros(height,width);
% Calculate the pixel values using a nested while loop
y = 1;
while y <= height
    x = 1;
    while x <= width
        if M(x,y) == 0
            p(y,x) = 255; %white pixel
        else %M(height,width) == 100
            p(y,x) = 0; %black pixel
        end
        x = x + 1;
    end
    y = y + 1;
end
% Write pixels to a PGM image file
% Open a file for writing
fid = fopen('image.pgm','w');
% Write the PGM image header to the file
fprintf(fid,'P2\n');
fprintf(fid,'%d %d\n', width, height);
fprintf(fid,'255\n');
% Write the pixel values from the matrix into
% the file
    y = 1;
    while y <= height
        x = 1;
        while x <= width
            fprintf(fid, '%03d ', p(y,x));
            x = x + 1;
        end
        fprintf(fid, '\n');
        y = y + 1;
    end
% Close the file
fclose(fid);