NAME

GD::RPPNG - Package for generating human only readable images

DESCRIPTION

GD::RPPNG - Package for generating human-only readable images

The GD::RPPNG (Random Password PNG) module was created to provide an easy access to human-only readable images. This is very usefull to avoid automatic processing of authentication. (ie: subscription to free email accounts).

SYNOPSIS

    use GD::RPPNG;

    # create a new image
    $myimage = new GD::RPPNG;

    # configure the image
    $myimage->Config (
        Xsize            => 400,
        Ysize            => 75,
        CharSet          => 'ABCDEFGHJKLMNPQRSTUVWXYZ23456789',
        CodeLen          => 8,
        FontMinPT        => 12,
        FontMaxPT        => 28,
        yDivert          => 10,
        Angle            => 45,
        XLinesFactor     => 10,
        YLinesFactor     => 10,
        Transparent      => 0,
        Colors           => 1,
        bgColor          => 'FFFFFF',
        fgColor          => '000000',
        Code             => 'mypasswd',
        DebugCode        => 0,
        );

    # add TrueType(C) fonts
    $myimage->AddFonts (
        '/usr/X11R6/lib/X11/fonts/truetype/arial.ttf',
        '/usr/X11R6/lib/X11/fonts/truetype/courier.ttf',
    );


    # generate the image
    ( $mycode, $mypng ) = $image->GenImage();

METHODS

$object = new GD::RPPNG

Creates a new object and sets all default options (see next METHOD for detailed description):

    Xsize         => 400
    Ysize         => 75
    CharSet       => 'ABCDEFGHJKLMNPQRSTUVWXYZ23456789'
    CodeLen       => 8
    FontMinPT     => 12
    FontMaxPT     => 28
    yDivert       => 10
    Angle         => 45
    XLinesFactor  => 10
    YLinesFactor  => 10
    Transparent   => 0
    Colors        => 1
    bgColor       => 'FFFFFF'
    fgColor       => '000000'
    Code          => ''
    DebugCode     => 0

$object->Config()

With this method you can override all the default options shown above.

'Xsize' defines the width of the image in pixels. here's an example:

    $object->Config( Xsize => 400 )

'Ysize' defines the height of the image in pixels. here's an example:

    $object->Config( Ysize => 75 )

'CharSet' defines the list of chars which may be used to generate the "code". Depending on the fonts you will use, its recommended to skip I,L,0,O and 1 as they might be confusing. here's an example:

    $object->Config( CharSet => 'ABCDEFGHJKMNOPQRSTUVWXYZ23456789%$#@' )

'CodeLen' defines the number of chars to be used to generate the "code". here's an example:

    $object->Config( CodeLen => 8 )

'FontMinPT' defines the minimal font size to use. here's an example:

    $object->Config( FontMinPT => 12 )

'FontMaxPT' defines the maximal font size to use. here's an example:

    $object->Config( FontMaxPT => 24 )

'yDivert' defines, in percent of the image height, the vertical range in which chars may be printed. here's an example:

    $object->Config( yDivert => 10 )

'Angle' defines, in degree, the angle range in which chars may be rotated. As an example, 90 will allow chars to be rotated from -45 to +45 degrees. here's an example:

    $object->Config( Angle => 45 )

'XLinesFactor' defines, in percent, the amount of horizontal lines to be draw. As an example, 50 on a 400 pixels wide image will draw about 200 lines. here's an example:

    $object->Config( XLinesFactor => 20 )

'YLinesFactor' defines, in percent, the amount of vertical lines to be draw. As an example, 50 on a 100 pixels high image will draw about 50 lines. here's an example:

    $object->Config( YLinesFactor => 20 )

'Transparent' defines if the background has to be transparent or not. here's an example:

    $object->Config( Transparent => 0 )

'Colors' defines if the image will use random colors or not. here's an example:

    $object->Config( Colors => 1 )

'bgColor' defines, in RRGGBB (hex) format, the background color to use. here's an example:

    $object->Config( bgColor => 'FFFFFF' )

'fgColor' defines, in RRGGBB (hex) format, the foreground color to use. here's an example:

    $object->Config( fgColor => '000000' )

'Code' defines the "code". If not set, a random code will be generated using the CharSet and the CodeLen options. If set, CharSet and CodeLen will be ignored. here's an example:

    $object->Config( Code => 'q12we34r' )

NOTE: You may specify multiple options at the same time here's an example:

    $object->Config(
        Xsize => 400,
        Ysize => 75,
        Colors => 1
   );

'DebugCode' defines if the "code" will be displayed on the top left of the image or not. NOTE: Do only use this for debugging purpose! here's an example:

$object->AddFonts()

With this method you can add TrueType fonts. Those fonts will be randomly used to draw the "code" on the image. here's an example:

    $object->AddFonts(
        '/usr/X11R6/lib/X11/fonts/truetype/arial.ttf',
        '/usr/X11R6/lib/X11/fonts/truetype/courier.ttf'
    );

$object->GenImage()

With this method you will generate the image. The method will return the "code" and the image in an array. here's an example:

    ($mycode, $myimage) = $object->GenImage();
    print "Content-type: image/png\n\n";
    print $myimage;

EXAMPLES

Many examples may be found at http://www.spale.com/gd-rppng

AUTHOR

Pascal Gloor <spale@cpan.org>

The GD::RPPNG module was written by Pascal Gloor.

VERSION

Version 0.9, released on 11 Dec 2003.

COPYRIGHT

GD::RPPNG Copyright (C) 2003 Pascal Gloor <spale@cpan.org>

GD Copyright (C) 1995-2000, Lincoln D. Stein.

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

SEE ALSO

GD::RPPNG