ConvertBitmapToSourceCode-ForOld-PBMlib-1.xx.pl

#!/usr/bin/perl

# Convert Bitmap to Source Code tool - Copyright (C) 2010 R. Diez
#
#     This program is free software: you can redistribute it and/or modify
#     it under the terms of the GNU Affero General Public License version 3 as published by
#     the Free Software Foundation.
#
#     This program is distributed in the hope that it will be useful,
#     but WITHOUT ANY WARRANTY; without even the implied warranty of
#     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#     GNU Affero General Public License version 3 for more details.
#
#     You should have received a copy of the GNU Affero General Public License version 3
#     along with this program.  If not, see L<http://www.gnu.org/licenses/>.

=head1 NAME

Convert Bitmap to Source Code 1.06

=head1 USAGE

S<perl ConvertBitmapToSourceCode.pl --output-format fmt [--invert-color] [--invert-bit-order] input.ppm output.h>

The input file must be in Portable Pixmap format (PPM), in text format (the type is then P3).
This format that can be generated by GIMP or by the ImageMagick tools.

The only output format currently supported is the C/C++ array syntax.

The main reason this tool exists is that ImageMagick does not currently support the RGB565 format
(as of May 2011), but this is a very popular display format among small hardware devices.

=head1 OPTIONS

=over

=item *

B<-h, --help>

Prints this help text.

=item *

B<--output-format> fmt

Available output formats are:
  monochrome
  rgb565

For the monochrome format, the input pixels must be completely white
or completely black, as this tool will not attempt to guess what colours
or color shades should be made white or black.

=item *

B<--license>

Prints the license.

B<--invert-color>

For the monochrome format, swap the black and white colours.

=item *

B<--invert-bit-order>

For the monochrome format, swap the bits at each byte.


=back

=head1 PREREQUISITES

Install the Image::PBMlib Perl module in advance. No other graphic or bitmap libraries are needed,
that's the reason why this tool insists on the PPM text format for the input bitmap data.

If you are using ActiveState's Perl on Windows, you can use the PPM tool to manually install that module,
or run the PPM tool like this for automatic installation:

  ppm install Image::PBMlib

If you are using some other Perl version or running on some other operating system,
you can install that module manually with CPAN, or run the following command for automatic installation:

  cpan -i Image::PBMlib

=head1 USAGE EXAMPLE

Say you have a MyBitmap.png file that you wish to convert to C source code in RGB565 format.
The output file should be called MyBitmap.h, and there will be an intermediate file called MyBitmap.ppm .
This bash script does the trick:

  #!/bin/bash
  set -o errexit
  set -o nounset

  # This 'convert' tool comes with the ImageMagick library, you'll have to install it beforehand.
  CONV_TOOL=convert

  CONV_BM_SCRIPT=/some/path/ConvertBitmapToSourceCode.pl

  FILENAME=MyBitmap.png
  "$CONV_TOOL" "$FILENAME" -format PPM -compress none "${FILENAME%.*}.ppm"
  "$CONV_BM_SCRIPT" --output-format rgb565 "${FILENAME%.*}.ppm" "${FILENAME%.*}.h"

=head1 EXIT CODE

Exit code: 0 on success, some other value on error.

=head1 TO-DO LIST

This tool could read and write many other image and source formats. Help is always welcome.

=head1 VERSION HISTORY

=over

=item *

Version 1.06: Use \A instead of ^, and \z instead of $, in regular expressions.

=item *

Version 1.05: All Perl scripts use Getopt::Long: option 'no_ignore_case' now.

=item *

Version 1.04 has just a tiny change in an error message.

=item *

Version 1.03, released in August 2011.

Added options --invert-color and --invert-bit-order. Minor fixes.

=item *

Version 1.00, released in May 2011.

=back

=head1 FEEDBACK

Please send feedback to rdiezmail-tools at yahoo.de

=head1 LICENSE

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License version 3 as published by
the Free Software Foundation.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Affero General Public License version 3 for more details.

You should have received a copy of the GNU Affero General Public License version 3
along with this program.  If not, see L<http://www.gnu.org/licenses/>.

=cut


use strict;
use warnings;

use Getopt::Long;
use Pod::Usage;
use IO::Handle;
# use Carp::Assert;  # Unfortunately, not all Perl distributions come with this module.

my $VERSION = "1.06";  # WARNING: If you update this version number, you need to manually update it in the help text above.

use constant TRUE  => 1;
use constant FALSE => 0;

use constant EXIT_CODE_SUCCESS       => 0;
use constant EXIT_CODE_FAILURE_ARGS  => 1;
use constant EXIT_CODE_FAILURE_ERROR => 2;


use constant INPUT_FORMAT_ASCII_PIXMAP => 3;

my %pnm_format_names =
(
  1 => "ascii bitmap",
  2 => "ascii graymap",
  3 => "ascii pixmap",
  4 => "raw bitmap",
  5 => "raw graymap",
  6 => "raw pixmap"
);

sub get_pnm_format_name ( $ )
{
  my $format_type_number = shift;

  my $format_name = $pnm_format_names{ $format_type_number };

  if ( not defined $format_name )
  {
      return "<unknown>";
  }

  return $format_name;
}


sub write_stdout ( $ )
{
  my $str = shift;

  ( print STDOUT $str ) or
     die "Error writing to standard output: $!\n";
}


sub write_to_file ( $ $ )
{
  my $file = shift;
  my $str  = shift;

  ( print $file $str ) or
     die "Error writing to file: $!\n";
}


sub get_cmdline_help_from_pod ( $ )
{
  my $pathToThisScript = shift;

  my $memFileContents = "";

  open( my $memFile, '>', \$memFileContents )
      or die "Cannot create in-memory file: $!\n";

  binmode( $memFile )  # Avoids CRLF conversion.
      or die "Cannot access in-memory file in binary mode: $!\n";

  pod2usage( -exitval    => "NOEXIT",
             -verbose    => 2,
             -noperldoc  => 1,  # Perl does not come with the perl-doc package as standard (at least on Debian 4.0).
             -input      => $pathToThisScript,
             -output     => $memFile );

  $memFile->close()
      or die "Cannot close in-memory file: $!\n";

  return $memFileContents;
}


#------------------------------------------------------------------------
#
# Removes leading and trailing blanks.
#
# Perl's definition of whitespace (blank characters) for the \s
# used in the regular expresion includes, among others, spaces, tabs,
# and new lines (\r and \n).
#

sub trim_blanks ( $ )
{
  my $retstr = shift;

  # POSSIBLE OPTIMISATION: Removing blanks could perhaps be done faster with transliterations (tr///).

  # Strip leading blanks.
  $retstr =~ s/\A\s*//;

  # Strip trailing blanks.
  $retstr =~ s/\s*\z//;

  return $retstr;
}


# Returns the error message that resulted from trying to load the given module,
# or undef if the module could be loaded without errors.

sub is_module_installed ( $ )
{
  # I don't really like the 'eval' way of checking whether a module is installed,
  # because all posible errors will be converted to a blind "module not installed" message.
  # Besides, that does not work for all modules, for example module Term::ReadLine::Gnu
  # may cause the following error:  "It is invalid to load Term::ReadLine::Gnu directly".
  # Maybe we could look at < perldoc -l ModuleName > for inspiration, because
  # perldoc does seem to find all modules.
  # We could also add to the "not installed" message the real error message,
  # from the eval, but that would be too verbose for the user.
  # Or do you know of a better way?

  my $moduleName = shift;

  my $statement = "require " . $moduleName . "; 1;";

  eval( $statement );

  if ( $@ )
  {
    return trim_blanks( $@ );
  }
  else
  {
    return undef;
  }
}


# Adds thousand separators, that is, turns a "1000000" into "1,000,000".

sub add_thousand_separators ( $ )
{
  # Source code copied from perlfaq5,
  # question "How can I output my numbers with commas added?".

  local $_ = shift; 1 while s/^([-+]?\d+)(\d{3})/$1,$2/; return $_;
}


sub generate_rgb565_source_code ( $ $ $ )
{
  my $header   = shift;
  my $pixels   = shift;
  my $out_file = shift;

  use integer;

  my $pos = 0;
  my $byte_count = 0;

  for ( my $row = 0; $row < $header->{ height }; ++$row )
  {
    for ( my $col = 0; $col < $header->{ width }; ++$col )
    {
      my ($r, $g, $b) = ( $pixels->[$pos][0], $pixels->[$pos][1], $pixels->[$pos][2] );

      # write_stdout( "Pixel values: $r, $g, $b\n" );

      $r /= 8; #  8 bits down to 5 bits.
      $g /= 4; #  8 bits down to 6 bits.
      $b /= 8; #  8 bits down to 5 bits.

      # write_stdout( "Pixel values: $r, $g, $b,  " );

      my $rgb565_hi = ( $r << 3 ) |( $g >> 3 );
      my $rgb565_lo = ( ( $g & 0x07 ) << 5 ) | $b;

      write_to_file( $out_file, sprintf( "0x%02X, 0x%02X,  ", $rgb565_hi, $rgb565_lo ) );

      $byte_count += 2;
      ++$pos;
    }

    write_to_file( $out_file, "\n" );
  }

  return $byte_count;
}


sub write_out_monochrome_byte ( $ $ $ )
{
  my $out_file   = shift;
  my $byte_value = shift;
  my $invert_bit_order = shift;

  my $unpack_format = $invert_bit_order ? "B8" : "b8";

  write_to_file( $out_file, "0b" . unpack( $unpack_format, pack( "V", $byte_value) ) . ", " );
}


sub add_monochrome_pixel ( $ $ $ $ $ $ )
{
  my $pixel_value = shift;
  my $invert_bit_order = shift;
  my $pixel_count = shift;
  my $byte_value  = shift;
  my $out_file    = shift;
  my $byte_count  = shift;

  $$byte_value <<= 1;
  $$byte_value |= $pixel_value;
  ++$$pixel_count;

  if ( $$pixel_count < 8 )
  {
    return;
  }

  write_out_monochrome_byte( $out_file, $$byte_value, $invert_bit_order );
  $$byte_count = $$byte_count + 1;

  $$pixel_count = 0;
  $$byte_value  = 0;
}


sub generate_monochrome_source_code ( $ $ $ $ $ )
{
  my $header   = shift;
  my $pixels   = shift;
  my $invert_color     = shift;
  my $invert_bit_order = shift;
  my $out_file = shift;

  use integer;

  my $width_in_bytes = ( $header->{ width } + 7 ) / 8;

  my $pos = 0;
  my $byte_count = 0;

  for ( my $row = 0; $row < $header->{ height }; ++$row )
  {
    my $pixel_count = 0;
    my $byte_value  = 0;

    for ( my $col = 0; $col < $header->{ width }; ++$col )
    {
      my ($r, $g, $b) = ( $pixels->[$pos][0], $pixels->[$pos][1], $pixels->[$pos][2] );

      my $pixel_value;

      if ( $r == 0 and $g == 0 and $b == 0 )
      {
        $pixel_value = $invert_color ? 1 : 0;
      }
      elsif ( $r == 255 and $g == 255 and $b == 255 )
      {
        $pixel_value = $invert_color ? 0 : 1;
      }
      else
      {
          die "Invalid pixel value R: $r, G: $g, B: $b\n";
      }

      add_monochrome_pixel( $pixel_value, $invert_bit_order, \$pixel_count, \$byte_value, $out_file, \$byte_count );

      ++$pos;
    }

    if ( $pixel_count != 0 )
    {
      for ( my $i = 0; $i < 8 - $pixel_count; ++$i )
      {
        $byte_value <<= 1;

        if ( $invert_color )
        {
          $byte_value += 1;
        }
      }

      write_out_monochrome_byte( $out_file, $byte_value, $invert_bit_order );
      $byte_count += 1;
    }

    write_to_file( $out_file, "\n" );
  }

  write_stdout( "Monochrome width in bytes: $width_in_bytes\n" );

  return $byte_count;
}


sub get_license_text ()
{
  return ( <<EOL

                    GNU AFFERO GENERAL PUBLIC LICENSE
                       Version 3, 19 November 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
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  11. Patents.

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  12. No Surrender of Others' Freedom.

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  13. Remote Network Interaction; Use with the GNU General Public License.

  Notwithstanding any other provision of this License, if you modify the
Program, your modified version must prominently offer all users
interacting with it remotely through a computer network (if your version
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                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

  If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.

  To do so, attach the following notices to the program.  It is safest
to attach them to the start of each source file to most effectively
state the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.

    <one line to give the program's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.

Also add information on how to contact you by electronic and paper mail.

  If your software can interact with users remotely through a computer
network, you should also make sure that it provides a way for users to
get its source.  For example, if your program is a web application, its
interface could display a "Source" link that leads users to an archive
of the code.  There are many ways you could offer source, and different
solutions will be better for different programs; see section 13 for the
specific requirements.

  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU AGPL, see
<http://www.gnu.org/licenses/>.

EOL
  );
}


# ----------- main Routine -----------

sub main ()
{
  # Parse command line.

  my $arg_help = 0;
  my $arg_h = 0;
  my $arg_outputFormat;
  my $arg_license = 0;
  my $arg_invert_color = 0;
  my $arg_invert_bit_order = 0;

  Getopt::Long::Configure( "no_auto_abbrev",  "prefix_pattern=(--|-)", "no_ignore_case" );

  my $result = GetOptions(
                 'help'              =>  \$arg_help,
                 'h'                 =>  \$arg_h,
                 'invert-color'      =>  \$arg_invert_color,
                 'invert-bit-orderr' =>  \$arg_invert_bit_order,
                 'output-format=s'   =>  \$arg_outputFormat,
                 'license'           =>  \$arg_license
                );

  if ( not $result )
  {
    # GetOptions has already printed an error message.
    return EXIT_CODE_FAILURE_ARGS;
  }

  if ( $arg_help || $arg_h )
  {
    write_stdout( get_cmdline_help_from_pod( $0 ) );
    return EXIT_CODE_SUCCESS;
  }

  if ( $arg_license )
  {
    my $licenseText = get_license_text();

    write_stdout( $licenseText );
    return EXIT_CODE_SUCCESS;
  }

  if ( not defined $arg_outputFormat )
  {
    die "Missing option --arg_outputFormat\n";
  }

  if ( 2 != scalar @ARGV )
  {
    die "Invalid number of arguments. Use argument --help for more information.\n";
  }

  if ( $arg_invert_color and $arg_outputFormat ne "monochrome" )
  {
    die "Option --invert-color only works with the monochrome output format.\n";
  }

  if ( $arg_invert_bit_order and $arg_outputFormat ne "monochrome" )
  {
    die "Option --invert-bit-order only works with the monochrome output format.\n";
  }

  my $src_file  = shift @ARGV;
  my $dest_file = shift @ARGV;


  my $module_name = "Image::PBMlib";

  my $load_err_msg = is_module_installed( $module_name ) ;

  if ( defined $load_err_msg )
  {
    die "Required module $module_name not installed. See the help text for details on how to install it. ".
        "In case it helps, the error message trying to load the module was: $load_err_msg\n";
  }

  require Image::PBMlib;  # I couldn't manage to use $module_name together with 'require'.


  open( my $f, "<", $src_file )
    or die "Can't open file \"$src_file\": $!\n";

  binmode( $f )  # Avoids CRLF conversion.
      or die "Cannot access file \"$src_file\" in binary mode: $!\n";

  my $header = Image::PBMlib::readppmheader( $f );

  if ( defined $header->{ error } )
  {
    die "Error: " . $header->{ error } . "\n";
  }

  my $format_name = get_pnm_format_name( $header->{ type } );

  write_stdout( "Reading \"$src_file\", format: " . $format_name . ", width: " . $header->{ width } . ", height: " . $header->{ height } . " ..." . "\n" );

  if ( $header->{ type } != INPUT_FORMAT_ASCII_PIXMAP )
  {
    die "Only the input format " . get_pnm_format_name( INPUT_FORMAT_ASCII_PIXMAP ) . " is currently supported.\n";
  }

  my @pixels = Image::PBMlib::readpixels_dec( $f,
                                              $header->{ type },
                                              $header->{ width } * $header->{ height } );

  if ( scalar(@pixels) != $header->{ width } * $header->{ height } )
  {
    die "Unexpected number of pixels read, " . scalar(@pixels) . " instead of " . $header->{ width } * $header->{ height } . ".\n";
  }

  close( $f ) or die "Can't close file descriptor: $!\n";


  write_stdout( "Generating C header file \"$dest_file\"... " );


  open( my $out_file, ">", $dest_file )
    or die "Can't open file \"$dest_file\": $!\n";

  binmode( $out_file )  # Avoids CRLF conversion.
      or die "Cannot access file \"$dest_file\" in binary mode: $!\n";

  my $data_byte_count;

  if ( $arg_outputFormat eq "monochrome" )
  {
    $data_byte_count = generate_monochrome_source_code( $header, \@pixels, $arg_invert_color, $arg_invert_bit_order, $out_file );
  }
  elsif ( $arg_outputFormat eq "rgb565" )
  {
    $data_byte_count = generate_rgb565_source_code( $header, \@pixels, $out_file );
  }
  else
  {
    die "Unsupported output format \"$arg_outputFormat\".\n";
  }

  close( $out_file ) or die "Can't close file descriptor: $!\n";

  write_stdout( "done, the generated C array is " . add_thousand_separators( $data_byte_count ) . " bytes long." . "\n" );

  return EXIT_CODE_SUCCESS;
}


eval
{
  my $exitCode = main();
  exit $exitCode;
};

my $errorMessage = $@;

# We want the error message to be the last thing on the screen,
# so we need to flush the standard output first.
STDOUT->flush();

print STDERR "\nError running $0: $errorMessage";

exit EXIT_CODE_FAILURE_ERROR;