NAME

GD::SecurityImage::AC - A drop-in replacement for Authen::Captcha.

SYNOPSIS

use GD::SecurityImage::AC;

# create a new object
my $captcha = Authen::Captcha->new();

# set the data_folder. contains flatfile db to maintain state
$captcha->data_folder('/some/folder');

# set directory to hold publicly accessable images
$captcha->output_folder('/some/http/folder');

# Alternitively, any of the methods to set variables may also be
# used directly in the constructor

my $captcha = Authen::Captcha->new(
  data_folder => '/some/folder',
  output_folder => '/some/http/folder',
  );

# create a captcha. Image filename is "$md5sum.png"
my $md5sum = $captcha->generate_code($number_of_characters);

# check for a valid submitted captcha
#   $code is the submitted letter combination guess from the user
#   $md5sum is the submitted md5sum from the user (that we gave them)
my $results = $captcha->check_code($code,$md5sum);
# $results will be one of:
#          1 : Passed
#          0 : Code not checked (file error)
#         -1 : Failed: code expired
#         -2 : Failed: invalid code (not in database)
#         -3 : Failed: invalid code (code does not match crypt)
##############

DESCRIPTION

This module is a drop-in GD::SecurityImage replacement for Authen::Captcha. Module is mostly compatible with Authen::Captcha. You can just replace

use Authen::Captcha;

line in your programs with

use GD::SecurityImage::AC;

to enable GD::SecurityImage interface. Alternatively, you can use

use GD::SecurityImage backend => 'AC';

Regular GD::SecurityImage interface is supported with an extra method: gdsi. Also see the CAVEATS section for incompatibilities.

This module uses: GD::SecurityImage, Digest::MD5, File::Spec and Fcntl modules.

If you are writing a captcha handler from scratch, this module is not recommended. You must use GD::SecurityImage directly. This module can be used for older Authen::Captcha applications only. And features are (and will be) limited with Authen::Captcha capabilities.

METHODS

See Authen::Captcha for the methods and usage.

gdsi

This method is used to set GD::SecurityImage parameters. Three methods are supported: new, create and particle. Parameter types and names are identical to GD::SecurityImage parameters:

$captcha->gdsi(new      => {name => value},
               create   => [param1, param2, ...],
               particle => [param1, param2]);

new is a hashref while the other two are arrayrefs. See GD::SecurityImage for information about these parameters.

gdsi method must be called just after creating the object:

my $captcha = Authen::Captcha->new;
$captcha->gdsi(
   new => {
            width    => 350,
            height   => 100,
            lines    => 10,
            font     => "/absolute/path/to/your.ttf",
            scramble => 1,
            ptsize   => 24,
   },
   create   => [ttf => 'box', '#80C0F0', '#0F644B'],
   particle => [115, 250],
);

If you don't use this method, the captcha image will be generated with default options.

gdsi returns the object itself. So, you can create your object like this:

my $captcha = Authen::Captcha->new( ... )->gdsi( ... );

CAVEATS

• width and height parameters are *not* character's width and height, but they define the image dimensions.

• No outside images. Captchas are generated with the GD::SecurityImage interface, not with third party "letter" graphics (but you can use true type fonts, see gdsi method). As a side effect, captcha size is not (actually "can not be") determined automatically. so, you have to specify a width and height value at the beginning.

• Setting images_folder has no effect.

• No background images. Backgrounds are drawn with GD::SecurityImage styles.

• You have to specify a TTF font, if you want to use another font (other than GD built-in GD::Font->Giant).

• Setting debug has no effect. You can still set debug, but it is not used inside this module.

SEE ALSO

GD::SecurityImage, Authen::Captcha.

AUTHOR

Burak Gürsoy, <burak@cpan.org>

COPYRIGHT

Copyright 2005 Burak Gürsoy. All rights reserved.

Some portions of this module adapted from Authen::Captcha. Authen::Captcha Copyright 2003 by First Productions, Inc. & Seth Jackson.

LICENSE

This library is provided "AS IS" without warranty of any kind.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.6 or, at your option, any later version of Perl 5 you may have available.