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use 5.006;
use strict;
use warnings;

our $VERSION = '0.11';

require Exporter;

our @ISA = qw(Exporter);

our %EXPORT_TAGS = ( 'mrm' => [ qw(MRM_RESTART
				   MRM_CUTOFF
				   MRM_FREEZE) ] );

our @EXPORT_OK = ( @{ $EXPORT_TAGS{'mrm'} } );
our @EXPORT = qw();

use constant MRM_RESTART => 1;
use constant MRM_CUTOFF => 2;
use constant MRM_FREEZE => 3;


require XSLoader;
XSLoader::load('Compress::PPMd', $VERSION);

sub Compress::PPMd::Encoder::deflate {
    if (wantarray) {
	return ($_[0]->encode($_[1]), 0)
    }
    $_[0]->encode($_[1])
}

sub Compress::PPMd::Decoder::inflate {
    if (wantarray) {
	return ($_[0]->decode($_[1]), 0)
    }
    $_[0]->decode($_[1])
}

sub Compress::PPMd::Encoder::flush {
    wantarray ? ("", 0) : ""
}

1;
__END__

=head1 NAME

Compress::PPMd - PPMd compression

=head1 SYNOPSIS

  use Compress::PPMd;

  my $encoder=Compress::PPMd::Encoder->new();
  my $encoded=$encoder->encode($text);
  my $encoded2=$encoder->encode($text2);

  my $decoder=Compress::PPMd::Decoder->new();
  my $decoded=$encoder->decode($encoded);
  my $decoded2=$encoder->decode($encoded2);


=head1 ABSTRACT

This package is a Perl wrapper around Dmitry Shkarin PPMd compression
library.

PPMd produces the best compression ratios for textual data.

=head1 DESCRIPTION

L<Compress::PPMd> is compossed of two classes to compress and
decompress data respectively:

=head2 Compress::PPMd::Encoder

=over 4

=item C<Compress::PPMd::Encoder-E<gt>new($MaxOrder, $MemSizeMB, $MRMethod, $Solid)>

creates a new encoder object. The parameters are:

=over 4

=item C<$MaxOrder>

max order for the PPM modelling ranging from 2 to 16, higher values
produce better compression ratios but are slower.

Default value is 8.

=item C<$MemSizeMB>

max memory in MB the compressor is able to use, bigger values improve
compression.

Default value is 4MB.

=item C<$MRMethod>

method of model restoration at memory insufficiency, possible values are:

=over 4

=item C<MRM_RESTART=1>

restart model from scratch (fast).

=item C<MRM_CUTOFF=2>

cut off model (default, slow).

=item C<MRM_FREEZE=3>

freeze model (faster but dangerous).

=back

Default value is C<MRM_CUTOFF>.