Convert SBPL GrapHic operand to pbm image file.

graphic2pbm.pl

use strict;
use warnings;
use utf8;

use v5.28;

use File::Basename;

if (!@ARGV || $ARGV[0] !~ /\.sbpl$/) {
  print qq($^X $0 graphic.sbpl && convert graphic.pbm graphic.png\n);
  exit(1);
}

my $input = $ARGV[0];
my $output = basename($input, '.sbpl') . '.pbm';
my ($width, $height, $graphic) = do {
  local $/;
  open my $fh, '<', $input or die $!;
  my ($w, $h, $g) = ($fh->getline =~ /\x{1b}GH(\d{3})(\d{3})([^\x{1b}]+)/);
  (int($w), int($h), $g)
};

open my $fh, '>', $output or die $!;
$fh->printf("P1\n%d %d\n", $width * 8, $height * 8) or die $!;
for (my $i = 0; $i < length $graphic; $i += $width) {
  my $row = substr($graphic, $i, $width);
  my @bin = map {sprintf('%04b', hex($_))} split(//, $row);
  $fh->say(join(' ', @bin)) or die $!;
}