NAME

Image::Pbm - Load, create, manipulate and save pbm image files.

SYNOPSIS

use Image::Pbm();

my $i = Image::Pbm->new(-width => 50, -height => 25 );
$i->line     ( 2, 2, 22, 22 => 1 );
$i->rectangle( 4, 4, 40, 20 => 1 );
$i->ellipse  ( 6, 6, 30, 15 => 1 );
$i->xybit    (       42, 22 => 1 );
print $i->as_string;
$i->save('test.pbm');

$i = Image::Pbm->new(-file,'test.pbm');

DESCRIPTION

This module provides basic load, manipulate and save functionality for the pbm file format. It inherits from Image::Xbm which provides additional functionality.

See Image::Base and Image::Xbm for a description of all inherited methods.

EXAMPLE

Imagine, we have to create self-contained web pages (with embedded images). Most browsers understand the xbm image format, but generating xbm files requires a certain effort (or a full fledged graphics software package). On the other hand, generating pbm files is easy. Indeed, it's more likely that you use your favorite text editor instead of Image::Pbm for that task. Reading pbm files is slightly more difficult. That's where the Image::[PX]bm modules come into play:

use Image::Pbm();

Image::Pbm->new(-file,'test.pbm')
  ->new_from_image('Image::Xbm')
    ->save('test.xbm');

Once we have xbm files, we can serve these images onto the Internet. To embed these images into a web page, we can use the "data" URL scheme:

http://www.ietf.org/rfc/rfc2397.txt

which requires the standard %xx hex encoding of URLs:

use URI::Escape();

my $data = URI::Escape::uri_escape( $xbm );

print qq(<img src="data:image/x-xbitmap,$data">);

This works with Mozilla and Opera. For Internet Explorer, we can use the following workaround:

print <<"HTML";
<pre id="xbm" style="display: none;">$xbm</pre>

<script>
  function xbm() { return document.getElementById('xbm').innerHTML; }
</script>

<img src="javascript:xbm()">
HTML

This works with Mozilla too.

TODO

Contact Mark Summerfield because the inheritance hierarchy

Image::Pbm <: Image::Xbm <: Image::Base

is suboptimal and should look like

Image::Xbm <:
              Image::Bitmap <: Image::Base
Image::Pbm <:

AUTHOR

Steffen Goeldner <sgoeldner@cpan.org>

COPYRIGHT

Copyright (c) 2004 Steffen Goeldner. All rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

SEE ALSO

perl, Image::Base, Image::Xbm, Image::PBMlib.