function image = readpgm(filename)%READPGM Read a raw pgm file as a matrix%%        IMAGE = READPGM(FILENAME) reads the binary PGM image data from%        the file named FILENAME and returns the image as a 2-dimensional%        array of integers IMAGE. Assumes the file is a raw PGM file%        containing 8-bit unsigned character data to represent pixel values.%% Matthew Dailey, 1997% Open the filefid = fopen(filename,'r');% Parse and check the header information.  No # comments allowed.A = fgets(fid);if strcmp(A(1:2),'P5') ~= 1  error('File is not a raw PGM');end;A = fgets(fid);sizes = sscanf(A,'%d');w = sizes(1);h = sizes(2);A = fgets(fid);max = sscanf(A,'%d');tlength = w*h;if max ~= 255 error('Cannot handle anything but 8-bit graymaps');end; % Read the raw data[v,count] = fread(fid,inf,'uchar');if count ~= tlength error('File size does not agree with specified dimensions.');end;% Pack the column vector v into the image matriximage = reshape(v,w,h)';fclose(fid);