RosettaCodeData/Task/Bitmap-Write-a-PPM-file/Prolog/bitmap-write-a-ppm-file-1.pro

:- module(bitmapIO, [
   write_ppm_p6/2]).

:- use_module(library(lists)).

%write_ppm_p6(File,Bitmap)
write_ppm_p6(Filename,[[X,Y],Pixels]):-
   open(Filename,write,Output,[encoding(octet)]),
   %write p6 header
   writeln(Output, 'P6'),
   atomic_list_concat([X, Y], ' ', Dimensions),
   writeln(Output, Dimensions),
   writeln(Output, '255'),
   %write bytes
   maplist(maplist(maplist(put_byte(Output))),Pixels),
   close(Output).