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package Imager::File::JPEG;
use 5.006;
use strict;
use Imager;
BEGIN {
our $VERSION = "0.97";
require XSLoader;
XSLoader::load('Imager::File::JPEG', $VERSION);
}
Imager->register_reader
(
type=>'jpeg',
single =>
sub {
my ($im, $io, %hsh) = @_;
($im->{IMG},$im->{IPTCRAW}) = i_readjpeg_wiol( $io );
unless ($im->{IMG}) {
$im->_set_error(Imager->_error_as_msg);
return;
}
return $im;
},
);
Imager->register_writer
(
type=>'jpeg',
single =>
sub {
my ($im, $io, %hsh) = @_;
$im->_set_opts(\%hsh, "i_", $im);
$im->_set_opts(\%hsh, "jpeg_", $im);
$im->_set_opts(\%hsh, "exif_", $im);
my $quality = $hsh{jpegquality};
defined $quality or $quality = 75;
if ( !i_writejpeg_wiol($im->{IMG}, $io, $quality)) {
$im->_set_error(Imager->_error_as_msg);
return;
}
return $im;
},
);
sub has_arith_coding {
my $cls = shift;
return $cls->has_encode_arith_coding && $cls->has_decode_arith_coding;
}
__END__
=head1 NAME
Imager::File::JPEG - read and write JPEG files
=head1 SYNOPSIS
use Imager;
my $img = Imager->new;
$img->read(file=>"foo.jpg")
or die $img->errstr;
$img->write(file => "foo.jpg")
or die $img->errstr;
my $version = Imager::File::JPEG->libjpeg_version();
if (Imager::File::JPEG->is_turbojpeg) { ... }
if (Imager::File::JPEG->is_mozjpeg) { ... }
if (Imager::File::JPEG->has_arith_coding) { ... }
=head1 DESCRIPTION
Imager's JPEG support is documented in L<Imager::Files>.
Besides providing JPEG support, Imager::File::JPEG has the following
methods:
=over
=item libjpeg_version()
Imager::File::JPEG->libjpeg_version();
Returns version information about the variety of C<libjpeg>
Imager::File::JPEG was compiled with. This is determined at build
time. This includes:
=over
=item *
The library type, one of C<libjpeg>, C<libjpeg-turbo> or C<mozjpeg>.
=item *
C<version> followed by the library version number.
=item *
C<api> followed by the C<libjpeg> API version.
=back
For C<libjpeg> the API and library versions are always equal.
=item is_turbojpeg()
Imager::File::JPEG->is_turbojpeg();
Returns true if Imager::File::JPEG was built with C<libjpeg-turbo>.
Note that C<mozjpeg> is built on top of C<libjpeg-turbo> so this will
return true for C<mozjpeg>.
=item is_mozjpeg()
Imager::File::JPEG->is_mozjpeg();
Returns true if Imager::File::JPEG was built with C<mozjpeg>. Note
that C<mozjpeg> doesn't define its own version numbering, so
C<mozjpeg> is detected by defines that only C<mozjpeg> currently
defines.
=item has_arith_coding()
Returns true if the C<libjpeg> variant C<Imager::File::JPEG> was built
with has both encoding and decoding support for arithmetic coding.
=item has_encode_arith_coding()
Returns true if the C<libjpeg> variant C<Imager::File::JPEG> was built
with has encoding support for arithmetic coding.
=item has_decode_arith_coding()
Returns true if the C<libjpeg> variant C<Imager::File::JPEG> was built
with has decoding support for arithmetic coding.
=back
=head1 AUTHOR
Tony Cook <tonyc@cpan.org>
=head1 SEE ALSO
Imager, Imager::Files.
=cut
|
