embed anything into a png

README.md

An image to make images ...

This little perl script makes an image out of anything ...

note: you'd need to have the program convert from imageMagick

download command:

curl -s https://i.postimg.cc/G2Ypy6sF/dat2png.png | convert png:- ppm:- | tail +4 > dat2png.pl

test and example:

echo "Why, Hello" > data.txt
curl -s https://i.postimg.cc/G2Ypy6sF/dat2png.png | convert png:- ppm:- | tail +4 | perl /dev/stdin  data.txt data.png
convert data.png ppm:- | tail +4

or

curl -s https://i.postimg.cc/G2Ypy6sF/dat2png.png | convert png:- ppm:- | tail +4 > dat2png.pl
echo "Hello world" | perl dat2png.pl | convert png:- ppm:- | tail +4

The images are gracefully hosted by postImages

README.png

build.sh

#

perl dat2png.pl -o dat2png.png data2png.pl
perl dat2png.pl -o README.png README.md
perl dat2png.pl -o build.png build.sh
perl dat2png.pl -o test.png test.sh

dat2png.pl

#!/usr/bin/perl

# this script take any data and make an image with it (format .ppm)
# $Previous: QmPYNQMhMbMjQed32su9q5eNCGurGozhbiSSrh6oGf2Dva$

# deps
#  convert from ImageMagick
our $dbug=0;
#--------------------------------
# -- Options parsing ...
#
my $if = undef;
my $of = undef;
while (@ARGV && $ARGV[0] =~ m/^-/)
{
  $_ = shift;
  #/^-(l|r|i|s)(\d+)/ && (eval "\$$1 = \$2", next);
  if (/^-v(?:erbose)?/) { $verbose= 1; }
  elsif (/^-?if?=?([\w.]+)?/) { $if= $1?$1:shift; }
  elsif (/^-?of?=?([\w.]+)?/) { $of= $1?$1:shift; }
  else                  { die "Unrecognized switch: $_\n"; }

}
#understand variable=value on the command line...
eval "\$$1='$2'"while $ARGV[0] =~ /^(\w+)=(.*)/ && shift;

my $data;
if (! defined $of) {
 if (@ARGV) { $of = pop @ARGV }
 else { $of = '-' }
}
if (defined $if) {
   local *IN; 
   local $/ = undef;
   open IN,'<',$if;
   $data = <IN>;
   close IN;
} else {
   if ($ARGV > 0) { $if = '<>'; }
     elsif ($#ARGV == 0) { $if = $ARGV[0]; }
     else { $if = '-'; }
   local $/ = undef;
   $data = <>;
   close STDIN;

}
my $size = length($data);

my $pi = atan2(0,-1);
#my $iratio = 4/3; # y/x
my $iratio = $pi; # x/y

my $xy = $size/3 * ($iratio);
my $x = sqrt($xy);
if ($verbose) {
   printf STDERR "if: %s\n",$if;
   printf STDERR "of: %s\n",$of;
   printf STDERR "size: %s\n",$size;
   printf STDERR "x: %.3f\n",$x;
   printf STDERR "y: %.3f\n",$x / $iratio;
}
my $y = int($x / $iratio + $iratio);
   $x = int( ( $size / 3 + $y - 1) / $y ); 
my $n = $x*$y*3;
my $delta = $n - $size;
if ($delta < 0) {
   $x++; 
   $n = $x*$y*3;
   $delta = $n - $size;
}
my $pad = "\x00" x $delta;
if ($verbose) {
   printf STDERR "playload: %sx%s = %s\n",$x,$y,$n;
   printf STDERR "delta: %s\n", $delta;
}

my $hdr = <<"EOS";
P6
$x $y
255
EOS

#my $fname = $file; $fname =~ s,.*/,,;
#my $bname = $fname; $bname =~ s/\.[^\.]*$//;
#printf STDERR "fname: %s\n",$fname;
#printf STDERR "fname: %s.png\n",$bname;

local *PPM; open PPM,"| convert -compress LZW -strip -quality 90 ppm:- png:$of";
print PPM $hdr;
binmode(PPM);
print PPM $data;
print PPM $pad;
close PPM;

exit $?;

1; # $Source: /my/perl/scripts/dat2png.pl$

dat2png.png

test.sh

echo "Why, Hello" > data.txt
curl -s https://i.postimg.cc/mDBJSLNw/dat2png.png | convert png:- ppm:- | tail +4 | perl /dev/stdin  data.txt data.png
convert data.png ppm:- | tail +4

rm data.txt data.png